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162 Cards in this Set
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117. What is the MOST appropriate radiation therapy dose for WHO grade II classical oligodendroglioma? |
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184. What is the next step in the management of a pilocytic astrocytoma located within the cerebellum that has been completely resected? (A) Continued observation (B) 45-50.4 Gy with close margins (C) Adjuvant temozolomide chemotherapy (D) Platinum-based adjuvant chemotherapy |
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173. Following 50-54Gy fractionated radiotherapy for an optic nerve sheath meningioma, the rate of blindness in the irradiated eye is approximately: (A) <5%. (B) 20%. (C) 50%. (D) >95%. |
Key: A Rationale: Despite affecting the optic nerve, fractionated irradiation has less than 5% risk of radiation-associated vision loss. It can improve vision in 75% of patients and obtains local control in over 95%. Surgery should not be performed for ONSMs. RT is the standard of care. References: Gondi, J Neurooncol 99, 2010. |
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39. Which tumor is associated with loss of INI1? (A) Pineoblastoma (B) Pineal germinoma (C) Supratentorial ependymoma (D) Atypical teratoid rhabdoid tumor |
Key: D Rationale: Atypical teratoid rhabdoid tumor is a embryonal posterior fossa tumor occurring almost exclusively in infants. Loss of INI1 is diagnostic and distinguishes this tumor from medulloblastoma. References: Pediatric Radiation Oncology 5th edition, 2011. |
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27. Following radiosurgery or surgery for brain metastases, the EORTC trial reported by Kocher et al, showed that whole brain irradiation improved the rate of: (A) overall survival. (B) treatment of related adverse events. (C) death due to intracranial progression. (D) duration of functional independence (time to WHO PS>2). |
Key: C Rationale: The addition of WBRT, as compared to observation, following surgery or radiosurgery, did not improve overall survival, functionally independent survival or side effects. The neurologic death rate was improved (44% vs 28% crude rate on WBRT vs Observation arms, respectively). References: Kocher JCO 29, 2011. PMID: 21041710. |
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315. The largest number of leptomeningeal carcinomatosis cases per year occurs with which of the following primary malignancies? A. Breast cancer B. Thyroid cancer C. Non-small cell lung cancer D. Malignant melanoma |
Correct answer is A. RATIONALE: Leptomeningeal carcinomatosis (LC) is found in 23% of patients with melanoma, 9% to 25% of patients with small cell lung cancer, and 5% of patients with breast cancer. Breast cancer is the most common diagnosis in patients with LC, however, because of the higher overall incidence of breast cancer in comparison. |
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137. What tumor is MOST LIKELY to change size during radiation therapy? (A) Meningioma (B) Oligodendroglioma (C) Craniopharyngioma (D) Brain metastasis from breast cancer |
Key: C Rationale: Craniopharyngiomas associated cysts can increase in size during radiation therapy. The other tumors listed are less likely to shrink or grow during fractionated treatment. References: Pediatric Radiation Oncology 5th edition, 2011. |
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305. Which of the following brain tumors occurs most commonly in children? A. Astrocytoma B. Ependymoma C. Medulloblastoma D. Germinoma |
Correct answer is A. RATIONALE: Astrocytomas make up approximately 30% of pediatric brain tumors in patients younger than 15 years of age and 20% of patients between 15 to 19 years of age per the Central Brain Tumor Registry of the United States (CBTRUS). Medulloblastoma is the most common posterior fossa tumor. Germinoma is more common in adolescent males. |
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229. The 10-year rate of local tumor failure for a WHO grade I meningioma following a Simpson grade I gross total surgical resection is approximately: (A) 10%. (B) 20%. (C) 30%. (D) 40%. |
Key: A Rationale: The 10 year rates of local failure following a Simpson grade I, II, III, IV resection are approximately 10, 20, 30 and 40%, respectively. High rates of local failure are seen with a ‘gross total resection’ in Simpson grade I-III resections. Patients need to be followed long term with imaging. References: Simpson J Neurol Neurosurg Psychiat 20, 1957. |
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230. What percentage of anaplastic astrocytomas exhibits contrast enhancement on MRI with gadolinium? (A) 65% (B) 80% (C) 85% (D) 95% |
Key: A Rationale: Approximately 50-70% of anaplastic astrocytomas exhibits contrast enhancement on MRI. References: Chaichana KL, Kosztowski T, Niranjan A, Olivi A, Weingart JD, Laterra J, Brem H, Quiñones-Hinojosa A.Prognostic significance of contrast-enhancing anaplastic astrocytomas in adults. J Neurosurg. 2010 Aug; 113(2):286-92. Keles GE, Chang EF, Lamborn KR, Tihan T, Chang CJ, Chang SM, et al.: Volumetric extent of resection and residual contrast enhancement on initial surgery as predictors of outcome. |
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281. Which of the following features is associated with improved overall survival in patients with low-grade gliomas? A. Intact 1p and 19q B. Bilateral involvement C. Pure astrocytic histology D. Age of less than 45 years |
Correct answer is D. RATIONALE: Younger age, oligodendroglial histology, 1p and 19q codeletion, resectable disease, and size <6 cm are associated with a better prognosis for patients with low-grade gliomas. |
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272. Which of the following doses of prophylactic cranial irradiation would be most appropriate for a 4-year-old boy with high-risk acute lymphoblastic leukemia? A. 18 Gy B. 23 Gy C. 36 Gy D. 45 Gy |
Correct answer is A. RATIONALE: For prophylactic treatment, 18 Gy is sufficient. Recent protocols use even lower doses of 12 Gy. |
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269. Which of the following treatments would be best for a patient with increasing T1 enhancement and T2 abnormality on a routine MRI 1 month after completion of concurrent temozolomide and 60 Gy of EBRT for glioblastoma? A. Bevacizumab and steroids B. Temozolomide and follow-up MRI C. PET scan to assess tumor metabolism D. Biopsy for further evaluation |
Correct answer is B. RATIONALE: Increased enhancement after chemoradiation is likely "pseudo-progression." The new RANO criteria address this phenomenon. Biopsy, steroids, or bevacizumab are not required. Most physicians would recommend commencing with adjuvant temozolomide. REFERENCE: Journal of Clinical Oncology (J Clin Oncol). 2010 Apr 10;28(11):1963-72. |
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257. Which of the following factors is associated with a favorable prognosis for patients with CNS germ cell tumors? A. Age of less than 3 years B. Elevated serum AFP level C. Pure germinoma histology D. Origin in the pineal gland |
Correct answer is C. RATIONALE: Unlike mixed germ cell tumors, pure CNS germinomas have an excellent prognosis after chemoradiation regimens or extended-field radiation therapy alone. Being less than 3 years of age is associated with worse event-free survival because of the reluctance to use radiation therapy. An elevated serum AFP level is diagnostic of a nongerminomatous component. The site of the disease (pineal vs. hypothalamic) is not of prognostic significance. |
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244. A 25-year-old patient has received radiosurgery for a 1.5 cm vestibular schwannoma and is being followed for a 0.3 cm contralateral intracanalicular lesion. The patient’s current symptoms include leg weakness and an enhancing intra-axial lesion at the T12 vertebral level. Which of the following diagnoses is most appropriate for the intra-axial lesion? A. Neurofibroma B. Ependymoma C. Low-grade astrocytoma D. Metastatic acoustic neuroma |
Correct answer is B. RATIONALE: Neurofibromatosis type 2 is characterized by bilateral vestibular schwannomas and associated with multiple meningiomas and ependymomas. The enhancing nature of the tumor at the T12 vertebral level suggests that it is not likely to be a low-grade astrocytoma. The intra-axial nature suggests it is not likely a neurofibroma. |
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231. Which of the following outcomes was associated with the addition of temozolomide to EBRT for patients with glioblastoma, according to long-term follow-up of the EORTC/NCIC randomized (Stupp, et al.) trial? A. Improved overall survival rate regardless of MGMT status B. No survival benefit in patients older than 70 years of age C. Survival benefit only for patients with a KPS of 80 D. Survival rate of 3% at 5 years |
Correct answer is A. RATIONALE: In the updated publication, overall survival was 10% after chemoradiation at 5 years. Patients older than 70 years of age were not eligible to be enrolled in this trial, so controversy remains as to the role of temozolomide in this group of patients. REFERENCE: Stupp, et al. EORTC/NCIC randomized trial. Lancet Oncology. 2009 May;10(5):459-466, (S1470-2045). |
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218. Which of the following types of ependymoma has the best prognosis? A. Thoracic spinal cord anaplastic B. Filum terminale myxopapillary C. Supratentorial clear cell D. Fourth ventricular |
Correct answer is B. RATIONALE: The myxopapillary subtype of ependymoma is a WHO grade I neoplasm. The sacral location is generally more likely to be surgically resectable. |
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211. The use of WBRT for brain metastases secondary to breast cancer is most likely to result in: A. a median survival rate of 8 to 10 months. B. an overall complete or partial response rate of 90% to 95%. C. improvement of neurologic symptoms in 45% to 55% of affected patients. D. improvement of cranial nerve deficits in 90% of affected patients. |
Correct answer is B. RATIONALE: Nieder, et al., studied volumetric response rates of brain metastases to WBRT. The overall complete or partial response rate was 93%, and patients with breast cancer tended to have favorable response rates in relation to other histologies. Median expected survival after treatment for brain metastases is 4 to 6.5 months vs. 1 to 2 months with supportive care only. Radiation provides durable improvement and/or stability in ~70% to 90% Radiation Oncology In-Training Exam 2011 63 of patients. For patients with cranial nerve deficits, approximately 40% may have improvement after WBXRT. MRI imaging should be done to confirm meningeal or skull base lesions so that these areas are included in the treatment field. REFERENCE: Lin NU, Ramakrishna NR. Brain metastases. Harris JR, Lippman ME, Morrow M, Osborne CK (eds). Diseases of the Breast. 4th ed. Chapter 81. Philadelphia: Lippincott Williams & Wilkins Publishers. 2010; p 982. |
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204. Which of the following statements about supratentorial primitive neuroectodermal tumor (S-PNET) is true? A. INI-1 deletion is commonly associated. B. S-PNET and medulloblastoma have identical genetic abnormalities. C. The survival rate is worse in patients with S-PNET than in those with infratentorial PNET. D. It is most commonly diagnosed in patients during the third decade of life. |
Correct answer is C. RATIONALE: Outcomes of supratentorial PNET (S-PNET) are worse than that of medulloblastoma (infratentorial PNET), with a progression-free survival rate of 49% vs. 78%, respectively. INI-1 deletion is found in ATRT. S-PNET is commonly diagnosed in younger patients. They have been found to have different cytogenetic abnormalities than medulloblastoma. REFERENCE: Timmermann B, et al. Journal of Clinical Oncology (J Clin Oncol). 2002;20:842-849. |
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197. Which of the following treatments is most appropriate for leptomeningeal metastases from breast cancer? A. WBRT for cranial nerve deficits B. Craniospinal irradiation C. Steroids to improve neurological symptoms D. Intrathecal chemotherapy after placement of a VP shunt |
Correct answer is A. RATIONALE: Radiation should be given to symptomatic areas whether or not structural disease is identified on imaging, as well as to sites of bulky disease. Radiation therapy is usually the most effective modality for treating focal leptomeningeal nodules. Radiation therapy to bulky sites may restore CSF flow. Use of complete neuro-axis irradiation is discouraged because it seldom controls the disease and is associated with significant toxicities, such as esophagitis and myelosuppression. Intrathecal chemotherapy cannot be given after placement of a VP shunt. REFERENCE: Fisher R, DeAngelis LM. Leptomeningeal metastasis. Harris JR, Lippman ME, Morrow M, Osborne CK (eds). Diseases of the Breast. 4th ed. Chapter 83. Philadelphia: Lippincott Williams & Wilkins Publishers. 2010; pp 1001-1007. |
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184. Which of the following adjuvant radiation therapies would be best to administer postoperatively to patients with supratentorial primitive neuroectodermal tumor (S-PNET)? A. A total dose of 54 Gy to the postoperative tumor bed alone B. A total dose of 36 Gy to the neuro-axis and a boost of 18 Gy to the postoperative bed C. A total dose of 36 Gy to the whole cranium and a boost of 18 Gy to the postoperative bed D. A total dose of 18 Gy to the neuro-axis and a boost of 36 Gy to the postoperative bed |
Correct answer is B. RATIONALE: German brain tumor trials HIT 88/89 and 91 have shown that a significant decrease in survival was associated with modifications to radiation therapy, such as reducing the total dose to the craniospinal axis or tumor region, omitting craniospinal radiation, or restricting the fields to the tumor region only. REFERENCE: Timmermann B, et al. Journal of Clinical Oncology (J Clin Oncol). 2002;20:842-849. |
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180. Epigenetic silencing of which of the following genes increases the effectiveness of temozolomide in patients with glioblastoma? A. PTEN B. EGFR C. CDKN2A D. MGMT |
Correct answer is D. RATIONALE: In randomized trials testing temozolomide plus radiation versus radiation only, those patients with hypermethylation and epigenetic silencing of the MGMT (O6-methylguanine-DNA-methyltransferase) gene derived the greatest benefit from temozolomide. |
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162. What is the most appropriate radiation dose for patients with Graves’ ophthalmopathy? A. 10 Gy in 5 fractions B. 20 Gy in 10 fractions C. 30 Gy in 15 fractions D. 40 Gy in 20 fractions |
Correct answer is B. REFERENCE: Marquez SD. Long-term results of irradiation for patients with progressive Graves' ophthalmopathy. International Journal of Radiation Oncology, Biology, Physics (Int J Radiat Oncol Biol Phys). 2001 Nov 1;51(3):766-74. |
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134. The risk for developing optic neuropathy after administration of 54 Gy of radiation in 28 fractions to a meningioma adjacent to the optic chiasm is: A. 1% at 5 years. B. 02% at 1 year. C. 15% at 1 year. D. 15% at 5 years. |
Correct answer is A. REFERENCE: Mayo C, Martel MK, Marks LB, Flickinger J, Nam J, Kirkpatrick J. QUANTEC: Radiation dose-volume effects of optic nerves and chiasm. International Journal of Radiation Oncology, Biology, Physics (Int J Radiat Oncol Biol Phys). 2010 Mar 1;76(3 Suppl):S28-35. Review. |
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70. For patients with craniopharyngioma, which structure is MOST LIKELY to be dose-limiting for radiosurgery treatment? (A) Retina (B) Brainstem (C) Optic chiasm (D) Mesial temporal lobe |
Key: C Rationale: Craniopharyngiomas most often present as cystic and solid masses in the suprasellar region and often about the optic structures including compression of the optic chiasm. The dose limit to the optic chiasm is 8-10 Gy in a single fraction. References: Pediatric Radiation Oncology 5th edition, 2011. |
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71. Which of the following patient positioning verification methods uses non-ionizing radiation? (A) Port films (B) Conebeam CT (C) Ultrasound guidance (D) Stereoscopic x-rays |
Key: C Rationale: Only ultrasound does not use ionizing radiation out of the options given. All other choices use x-rays which are ionizing. |
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120. When should initial imaging surveillance be performed once conformal radiation therapy has started for a patient with cystic craniopharyngioma? A. 1 to 2 weeks after the start of therapy B. 6 to 8 weeks after the start of therapy C. 3 to 6 months after the start of therapy D. 8 to 12 months after the completion of therapy |
Correct answer is A. RATIONALE: It is important to minimize the amount of normal brain that is in the treatment fields to reduce toxicity with conformal planning and reproducible in an effort to keep the treated volume as low as possible. Craniopharyngioma cysts, however, have been shown to change in size and shape during and after radiation therapy. Adaptive radiation therapy techniques have been used to ensure adequate conformal coverage of the tumor and the associated cysts. Weekly-biweekly imaging has been used to monitor the size and shape of the cyst. If there is a significant change noted, replanning with the new tumor volume can be performed. REFERENCE: Winkfield KM, et al. Surveillance of craniopharyngioma cyst growth in children treated with proton radiation therapy. International Journal of Radiation Oncology, Biology, Physics (IJROBP). 2009 Mar 1;73(3):716-21. |
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106. What cytogenetic finding is associated with oligodendroglioma? A. Loss of heterozygosity of 11q B. Co-deletion of 1p and 19q C. Deletion of 16p D. Deletion of 22p |
Correct answer is B. RATIONALE: Co-deletion of 1p and 19q has been found to be specific to oligodendroglioma and confers a better prognosis and increased sensitivity to both chemotherapy and radiation therapy. |
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92. What is the most appropriate treatment after gross total resection of a 3 cm, right frontal, low-grade astrocytoma in an otherwise healthy 40-year-old patient? A. Surveillance B. Temozolomide alone C. EBRT, followed by temozolomide D. EBRT alone |
Correct answer is A. RATIONALE: Surveillance would be the best option for a completely resected low-grade glioma. If recurrence is noted, radiation therapy should be considered. Chemotherapy is of unclear benefit in an adult with low-grade astrocytoma. |
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76. Which of the following treatments would be most appropriate for a 3 cm pituitary mass with optic chiasm compression? A. SRS, 15 Gy in a single fraction B. WBRT, 45 to 50 Gy in 25 fractions C. Biopsy, followed by radiation therapy D. Resection with reassessment for further therapy |
Correct answer is D. RATIONALE: For a large pituitary mass with chiasmal compression, an effort should be made to surgically decompress the optic chiasm and maximally debulk the tumor. Postoperative radiation therapy can be considered once the extent of the resection has been determined and postoperative changes have been stabilized. |
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60. Radiation therapy has the greatest effect in the shortest amount of time for which of the following conditions? A. Acromegaly B. Prolactinoma C. TSH-secreting adenoma D. Cushing’s disease |
Correct answer is A. RATIONALE: Radiation therapy (more commonly radiosurgery) has been effective in treating acromegaly with reduction in GH and IGF-1 by approximately 50% within the first two years and continued reduction over time. Radiation therapy is also effective in treating the other secreting adenomas; however, results may take longer. |
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59. According to the Collaborative ocular melanoma study (COMS) protocol guidelines, the dose prescription point for the radiation treatment of an ocular melanoma is: A. fixed at a depth of 5 mm. B. at the tumor apex. C. at the tumor apex if the tumor height is <5 mm, and at a depth of 5 mm if the tumor height is >5 mm. D. at the tumor apex if the tumor height is >=5 mm, and at a depth of 5 mm if the tumor height is <5 mm. |
Correct answer is D. RATIONALE: According to the collaborative ocular melanoma study (COMS) protocol, the prescription point is at the tumor apex for tumors that are 5 mm or greater in height, and at 5 mm for tumors that are less than 5 mm in height. The American Brachytherapy Society (ABS), on the other hand, recommends a prescription point at the tumor apex. REFERENCE: http://www.jhu.edu/wctb/coms/index.htm (General information: Radiation Therapy). Nag S, et al. International Journal of Radiation Oncology, Biology, Physics (Int J Radiat Oncol Biol Phys). 2003;56(2):544-555. |
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189. What is the MOST appropriate treatment for a 23-year-old male with a suprasellar germinoma with no evidence of neuroaxis dissemination and normal βhCG and α-fetoprotein levels? (A) Chemotherapy alone (B) Involved field radiation therapy (C) Whole ventricular irradiation followed by involved field radiation therapy (D) Combined chemotherapy and craniospinal irradiation followed by involved field radiation therapy |
Key: C Rationale: Among the 4 options, option C is most appropriate for localized CNS germinoma, which is radiosensitive. References: Rogers SJ, Mosleh-Shirazi MA, Saran FH. Radiotherapy of localised intracranial germinoma: time to sever historical ties? Lancet Oncol. 2005 Jul; 6(7):509-19 Review. |
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161. What is the most appropriate treatment for a 20-year-old male with a biopsy suggestive of suprasellar germinoma with no evidence of neuroaxis dissemination but with markedly elevated βhCG and α-fetoprotein levels? (A) Chemotherapy alone (B) Craniospinal irradiation followed by involved field radiation therapy (C) Whole ventricular irradiation followed by involved field radiation therapy (D) Combined chemotherapy and craniospinal irradiation followed by involved field radiation therapy |
Key: D Rationale: With markedly elevated markers, even with a germinoma histology, the patient should be managed like non-germinomatous germ cell tumor. Among the 4 options, option B (combined radiotherapy and chemotherapy) is the most appropriate option. References: Kretschmar C, Kleinberg L, Greenberg M, Burger P, Holmes E, Wharam M. Pre-radiation chemotherapy with response-based radiation therapy in children with central nervous system germ cell tumors: a report from the Children's Oncology Group. Pediatr Blood Cancer 2007 Mar; 48(3):285-91. |
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44. Which of the following syndromes is associated with an increased risk for the development of meningioma? A. Gorlin syndrome B. von Hippel-Lindau C. Tuberous sclerosis D. Neurofibromatosis type 2 |
Correct answer is D. RATIONALE: Neurofibromatosis type 2 is associated with an increased risk for the development of meningioma, although the most common tumors are vestibular schwannomas. Other risk factors are radiation exposure, female gender, African/African American race, and increased age. |
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27. What histopathologic criterion is required for the diagnosis of anaplastic (malignant) meningioma, according to the WHO 2000 classification? A. Invasion into the brain parenchyma B. MIB-1 labeling index of 20% by immunohistochemistry C. More than 20 mitotic figures per 10 high-power field D. More than 30 mitotic figures per 10 high-power field |
Correct answer is C. RATIONALE: Invasion into the brain parenchyma is no longer pathognomonic of an anaplastic (malignant) classification. The MIB labeling index is not used for the WHO classification. Current histopathologic criteria require more than 20 mitotic figures per 10 high-power field (HPF) for the diagnosis of anaplastic (malignant) meningioma. |
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12. According to Patchell's study of patients with a solitary brain metastasis, what percentage of them were found to have an unexpected histology after resection or biopsy, followed by WBRT? A. 06% B. 11% C. 16% D. 21% |
Correct answer is B. RATIONALE: In Patchell’s study, 6 of 54 eligible patients thought to have a solitary brain metastasis were found to have a second primary tumor or a nonmalignant pathology after resection or biopsy. |
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284. For a WHO grade I meningioma, the expected 10-year local control following 50-54 Gy fractionated irradiation is: (A) <50%. (B) 70%. (C) 80%. (D) >90%. |
Key: D Rationale: Local control ranges from 90% to 100% following radiotherapy. References: Gondi, J Neurooncol 99, 2010. |
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326. Which of the following conditions is LEAST likely to benefit from gross total resection? A. Posterior fossa ependymoma B. Third ventricular germinoma C. Suprasellar yolk sac tumor D. Medulloblastoma |
Correct answer is B. RATIONALE: Patients with CNS germinomas have a greater than 90% overall survival rate with radiation- or chemoradiation-based therapies. Gross total resection is not required. |
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319. Which of the following types of ependymoma most commonly occurs in the cauda equina? A. Subependymoma B. Tanycytic ependymoma C. Myxopapillary ependymoma D. Anaplastic ependymoma |
Correct answer is C. RATIONALE: Myxopapillary ependymomas are common in the cauda equina and have a better prognosis than other types. |
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311. Which of the following outcomes is most likely to be observed in patients who receive an SRS boost in combination with fractionated radiation therapy and chemotherapy for glioblastoma? A. Improved progression-free and overall survival B. Improved progression-free survival but not overall survival C. Improved local tumor control and quality of life D. No change in overall survival or quality of life |
Correct answer is D. RATIONALE: RTOG 9305 showed no benefit for any endpoint to upfront radiosurgery in the treatment of glioblastoma. |
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305. Which of the following chemotherapy drugs is mostly likely to decrease the contrastenhanced tumor volume in patients with glioblastoma? A. BCNU B. Irinotecan C. Bevacizumab D. Temozolomide |
Correct answer is C. RATIONALE: Bevacizumab is an anti-VEGF monoclonal antibody that can decrease tumor enhancement even if the T2-weighted or FLAIR MRI signal abnormality is increasing. |
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284. What is the most appropriate management for an unresectable, progressive, nonfunctioning pituitary macroadenoma with a mass effect on the optic chiasm? A. Single-fraction SRS B. Permanent interstitial brachytherapy with 125I seeds C. Hypofractionated stereotactic radiation therapy D. Conventionally fractionated EBRT |
Correct answer is D. RATIONALE: Conventional fractionated external-beam radiation therapy (EBRT) would be recommended with a dose of 45 to 50 Gy in 5 to 5.5 weeks. A larger daily fraction size is not recommended for tumors that are abutting the optic chiasm. Brachytherapy is not recommended because of the proximity to the optic chiasm. |
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250. Which of the following factors is associated with an increased risk for the development of meningioma? A. Cranial irradiation B. Testosterone therapy C. Neurofibromatosis type 1 D. Ovarian cancer |
Correct answer is A. RATIONALE: An increased risk for the development of meningioma is associated with women, patients with neurofibromatosis (NF) type 2 or breast cancer, pregnant patients, and patients who have received cranial irradiation. |
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235. According to the RTOG 9508 (Andrews) trial, which of the following should be the standard treatment for patients with one to three brain metastases? A. Surgery, followed by WBRT and an SRS boost B. WBRT, followed by an SRS boost C. WBRT alone D. SRS alone |
Correct answer is B. RATIONALE: Whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) boost improved functional autonomy (KPS) for all patients, and these treatments improved survival for patients with a single unresectable brain metastasis. Therefore, WBRT and SRS boost should be standard treatment for patients with a single unresectable brain metastasis, and they should be considered for patients with two or three brain metastases. REFERENCE: Andrews, et al. Lancet. 2004;363(9422):1665-72. |
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231. Which of the following hereditary syndromes is most likely to be found in a 1-year-old patient who has an enlarged abnormally enhancing optic chiasm? A. Neurofibromatosis B. Tuberous sclerosis C. von Hippel-Lindau D. Li-Fraumeni |
Correct answer is A. RATIONALE: An enlarged, abnormally enhancing optic chiasm in a 1- year-old patient is suggestive of an optic nerve glioma, which is associated with neurofibromatosis, type 1. Tuberous sclerosis is associated with subependymal giant cell tumors; von Hippel Lindau disease is associated with hemangioblastomas; Li-Fraumeni is associated with brain tumors and other tumors. |
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221. What was the local recurrence rate of a single brain metastasis after resection and observation, according to the randomized trial that evaluated WBRT versus observation after resection of a single brain metastasis as reported by Patchel? A. 16% B. 26% C. 36% D. 46% |
Correct answer is D. RATIONALE: A 46% rate of local recurrence at the original site was reported after surgery alone, which was 10% in the group receiving WBRT. Distant brain metastasis occurred in 37% versus 7% in the observation vs. WBRT groups, respectively. REFERENCE: Patchel. JAMA. 1988;280:1485-1489. |
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206. Which of the following characteristics are associated with the best overall survival in a patient with glioblastoma? A. Age of <30 years; unmethylated MGMT B. Age of <50 years; methylated MGMT C. Age of >50 years; unmethylated MGMT D. Age of >70 years; methylated MGMT |
Correct answer is B. RATIONALE: Epigenetic silencing of the MGMT DNA repair gene by promoter methylation compromises DNA repair and has been associated with longer survival in patients with glioblastoma who receive alkylating agents. Younger patients have a better survival rate than older patients. REFERENCES: Hegi ME, Diserens AC, Gorlia T, et al. MGMT gene silencing and benefit from temozolomide in glioblastoma. New England Journal of Medicine (NEJM). 2005;352:997-1003. Stupp R, Hegi ME, Mason WP, et al. Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomized phase III study: 5-year analysis of the EORTC-NCIC trial. Lancet Oncology. 2009;10:459-466. |
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191. An MRI scan performed 1 month after completion of chemoradiation with temozolomide for glioblastoma reveals enlargement of the contrast-enhanced lesion. Which of the following management options would be most appropriate? A. Second-line chemotherapy B. Continuation of temozolomide C. Resection of the lesion D. SRS to the lesion |
Correct answer is B. RATIONALE: Enlargement of the contrast-enhanced tumor 1 month after chemoradiotherapy with temozolomide (TMZ) may occur in approximately 50% of patients. However, with repeat imaging 2 months later, 64% displayed stable or reduced enhancement, indicative of pseudo-progression rather than true early progressive disease. Median overall survival for patients with pseudo-progression was 38 months versus 10 months for true progression. Given the incidence of pseudo-progression, the standard planned treatment with adjuvant TMZ is typically continued until further imaging is obtained several months later. REFERENCE: Brandes AA, Franceschi E, Tosoni A, et al. MGMT promoter methylation status can predict the incidence and outcome of pseudo-progression after concomitant radiochemotherapy in newly diagnosed glioblastoma patients. Journal of Clinical Oncology (J Clin Oncoll). 2008;26:2192-2197. |
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176. What is the 5-year overall survival rate for patients with glioblastoma treated with temozolomide (TMZ) and radiation therapy compared to radiation therapy (RT) alone? TMZ + RT RT alone A. 40% 10% B. 27% 11% C. 10% 2% D. 2% 1% |
Correct answer is C. RATIONALE: The addition of TMZ to RT increases overall survival for patients with glioblastoma multiforme. The 2-year overall survival rate with RT plus temozolomide is 27%, and the 5-year overall survival rate is 10%. REFERENCE: Stupp R, Hegi ME, Mason WP, et al. Effects of radiotherapy with concomitant and adjuvant temozolomide versus radiotherapy alone on survival in glioblastoma in a randomized phase III study: 5-year analysis of the EORTC-NCIC trial. Lancet Oncology. 2009;10:459-466. |
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172. Cranial radiation therapy is most appropriate for adults who have: A. CNS-positive leukemia and are receiving CNS-directed therapy in conjunction with intrathecal chemotherapy. B. acute lymphoid leukemia with any presentation and did not receive intrathecal chemotherapy or CNS-directed therapy. C. acute lymphoid leukemia due to their high risk for disease-related CNS relapse. D. acute myeloid leukemia due to their high risk for disease-related CNS relapse. |
Correct answer is A. RATIONALE: CNS prophylaxis, although effective at reducing the incidence of CNS relapse, has no significant effect on systemic relapse or overall survival, and cranial irradiation is used in conjunction with intrathecal chemotherapy for CNS-positive leukemia. REFERENCE: De Vita, et al. Principles and Practice of Oncology. |
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161. Which of the following management options is most appropriate for an intracranial nongerminomatous germ cell tumor after surgical resection? A. Irradiation of the whole brain B. Irradiation of the tumor plus the surgical margin C. Platinum-based chemotherapy, followed by craniospinal irradiation D. Surveillance if postoperative imaging confirms gross total resection |
Correct answer is C. RATIONALE: Compared to intracranial germinomas, non-germinomatous germ cell tumors (NGGCT) have a worse prognosis. NGGCT are more resistant to radiation and should not be treated with radiation therapy alone. Several reports indicate that complete and partial responses can be achieved in 80% of the patients who have NGGCT and receive platinum-based chemotherapy. However, chemotherapy alone results in high rates of recurrence. Additionally, relapse rates are higher in patients undergoing local field radiation therapy (RT) only. Therefore, adjuvant craniospinal irradiation is recommended for all patients, followed by a boost to the primary site. REFERENCES: Balmaceda C, Heller G, Rosenblum M, et al. Chemotherapy without irradiation−a novel approach for newly diagnosed CNS germ cell tumors: results of an international cooperative trial. The First International Central Nervous System Germ Cell Tumor Study. Journal of Clinical Oncology (J Clin Oncol). 1996;14(11):2908- 15. Kellie SJ, Boyce H, Dunkel IJ, et al. Primary chemotherapy for intracranial nongerminomatous germ cell tumors: results of the second international CNS germ cell study group protocol. Journal of Clinical Oncology (J Clin Oncol). 2004;22(5):846-53. |
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150. Which of the following factors increases the risk for CNS dissemination in a patient with retinoblastoma? A. Extension into the orbital fat B. Invasion of >50% of the choroid C. Presence of multiple intraocular tumors D. Involvement of the optic nerve beyond the lamina cribrosa |
Correct answer is D. RATIONALE: Involvement of the optic nerve beyond the lamina cribrosa is a known risk factor for CSF spread because of the access of retinoblastoma cells to the subarachnoid space (the optic nerve is surrounded by meninges). REFERENCE: Halperin EC, Kirkpatrick JP. Retinoblastoma. Pediatric Radiation Oncology. 4th edition. Chapter 5. Philadelphia: Lippincott Williams & Wilkins Publishers. pp 135-176. |
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131. What is the median overall survival time for patients who have anaplastic oligodendrogliomas with 1p19q codeletion treated with sequential PCV chemotherapy with radiation therapy? A. <1 year B. 3 years C. 5 years D. >7 years |
Correct answer is D. RATIONALE: In patients with 1p19q codeleted tumors, the median survival has not been reached with 7 to 8 years of follow-up. Patients who have tumors with intact 1p19q chromosomes had a median survival of only 1.8 and 2.8 years, based on the EORTC and RTOG trials. REFERENCES: van den Bent MJ, Carpentier AF, Brandes AA, et al. Adjuvant procarbazine, lomustine, and vincristine improve progression-free survival but not overall survival in newly diagnosed anaplastic oligodendrogliomas and oligo-astrocytomas: a randomized European Organization for Research and Treatment of Cancer phase III trial. Journal of Clinical Oncology. 2006;24:2715-2722. Cairncross G, Berkey B, Shaw E, et al. Phase III trial of chemotherapy plus radiotherapy compared with radiotherapy alone for pure and mixed anaplastic oligodendroglioma: Intergroup Radiation Therapy Oncology Group Trial 9402. Journal of Clinical Oncology. 2006;24:2707-2714. |
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10. Which of the following types of cancer most commonly metastasizes to the eye in women? A. Lung B. Breast C. Colon D. Thyroid |
Correct answer is B. RATIONALE: The most common choroidal metastasis arises from breast cancer in women and from lung cancer in men. |
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1. What total dose delivered with conventional fractionation would yield a 5% risk of blindness 5 years after irradiation of the entire retina? A. 25 Gy B. 35 Gy C. 45 Gy D. 55 Gy |
Correct answer is C. REFERENCES: Joiner and van der Kogel. Basic Clinical Radiobiology. 4th edition, 2009, Chapter 13. Hall and Giaccia. Radiobiology for the Radiologist. 6th edition. 2006. Chapter 19. |
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211. Which one of the following statements about pituitary adenomas is NOT CORRECT? A. Medical therapy for prolactinomas is bromocriptine B. The dose to the optic chiasm should be restricted to 8-10 Gy when considering radiosurgery C. 4500 cGy in 25 fractions is an appropriate dose for a recurrent pituitary adenoma D. Medical therapy for acromegaly is ketoconazole |
Answer 211 is D. Medical therapy for acromegaly is somatostatin. |
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212. For a patient with standard-risk medulloblastoma undergoing craniospinal irradiation, which one of the chemotherapy agents is given concurrently? A. Vincristine B. Bleomycin C. Temozolomide D. Carmustine (BCNU) |
Answer 212 is A. Vincristine is given with CSI. |
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255. Which of the following is the MOST important prognostic factor predicting survival for patients with ependymoma? (A) Age (B) Location (C) Extent of resection (D) Clinical target volume |
Key: C Rationale: Extent of resection is the most important prognostic factor. Presence of gross residual disease is associated with worse outcomes. References: Merchant TE. Current management of childhood ependymoma. Oncology (Williston Park). 2002 May; 16(5):629-42, 644; discussion 645-6, 648, Review. |
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213. Which one of the following statements about meningiomas is INCORRECT? A. Radiation therapy is not indicated after gross total resection of a benign meningioma B. Radiation therapy is indicated after gross total resection of a malignant meningioma C. The incidence of benign meningiomas is equal in men and women D. Chemotherapy is not recommended for a patient with a subtotally resected meningioma |
Answer 213 is C. Benign meningiomas are more frequent in women. |
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214. Which one of the following best estimates the median survival for a 45-year-old glioblastoma multiforme (GBM) patient who has undergone gross total resection and has a Karnofsky performance status (KPS) of 90? A. 60 months B. 30 months C. 18 months D. 11 months |
Answer 214 is C. Based on the RTOG RPA for malignant gliomas, the patient would be class III, with an estimated survival of 17.9 months. |
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215. Which one of the following molecular markers BEST predicts radiation and chemotherapy response for anaplastic oligodendroglioma? A. 1p B. 10p C. 19p D. 21p |
Answer 215 is A. Loss of 1p has been shown to significantly influence survival for patients with AO. |
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239. Which one of the following statements is CORRECT concerning metastatic disease to the orbit? A. The retina is the most common site within the orbit for metastasis B. Most patients present with decreased visual acuity and blurred vision rather than pain C. Biopsy is necessary to confirm diagnosis (even if a primary is known) and rule out melanoma D. Tilting lateral fields anteriorly 10 degrees is necessary to avoid irradiating the contralateral cornea and lens |
Answer 239 is B. The choroid is most common site. Most diagnoses of choroidal metastases are made clinically. Biopsy should be performed only if primary is unknown. |
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240. Regarding choroidal melanoma, which one of the following is CORRECT? A. In the Collaborative Ocular Melanoma Study (COMS) randomized trial for medium sized tumors treated with I-125, radiation affected vision in less than 20% of these cases B. In the randomization between enucleation vs plaque, there was no difference seen in mortality C. In a trial with enucleation vs plaque, 10-year follow-up showed that 50% of patients in the radiation arm had died D. Photocoagulation and cryotherapy are treatment options for medium-sized ocular melanomas |
Answer 240 is B. There is no difference in mortality between enucleation and plaque. Approximately 20% of patients die at 10 years in either arm, and close to 50% of patients receiving radiation experience impairment of vision. |
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194. Which of the following drugs is most appropriate for treating a secreting adrenocorticotropic hormone-releasing factor pituitary adenoma? A. Bromocriptine B. Somatostatin C. Octreotide D. Mitotane |
Answer 194 is D. Mitotane, ketoconazole, and metyrapone have been used to treated ACTH secreting tumors. |
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204. Which of the following syndromes is associated with medulloblastoma? A. Tuberous sclerosis B. Neurofibromatosis type 2 C. von Hippel-Lindau syndrome D. Gorlin syndrome |
Answer 204 is D. Gorlin syndrome (basal cell nevus syndrome) is autosomal dominant disease linked with higher risk for development of medulloblastoma. |
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206. Which of the following statements about myxopapillary ependymomas is true? A. Radiation therapy is commonly administered after complete resection of the tumors. B. Postsurgical chemotherapy has been shown to improve patient survival time. C. These tumors occur more commonly in the proximal than in the distal portion of the spinal cord. D. According to the WHO classification system, they are low-grade tumors. |
Answer 206 is D. Surgical resection is primary treatment modality for myxopapillary ependymomas and because of low grade and indolent nature of this tumor radiotherapy is only indicated after recurrence or incomplete resection. |
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210. Which of the following statements about craniopharyngioma is true? A. Microscopic examination of this tumor reveals a high mitotic index. B. Ocular symptoms commonly precede endocrine manifestations. C. External-beam radiation therapy consisting of 66 Gy is indicated after subtotal resection of the tumor. D. Gross total resection can often cause neuroendocrine and visual damage. |
Answer 210 is D. Neuroendocrine and vision damage are the most common complications from surgery especially if complete resection is attempted. External beam radiotherapy dose is usually limited to 50-55 Gy because of tumor proximity to optic chiasm. |
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212. The risk of radiation-induced scleral rupture following administration of high-dose (> 85 Gy) radioactive eye plaque therapy is what percentage? A. < 1% B. 10% C. 20% D. 30% |
Answer 212 is A. The sclera is very radioresistant. |
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215. For men, the most common metastases to the orbit originate from which of the following types of cancers? A. Lung B. Breast C. Colon D. Head and neck |
Answer 215 is A. Breast is the most common in females; lung is the most common in men. |
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218. Which of the following treatments is the primary modality for a patient with Graves ophthalmopathy? A. Orbital irradiation B. Steroid therapy C. Surgical decompression D. Combined modality (steroid and radiation) |
Answer 218 is B. Many patients do respond to steroids as initial therapy. Radiation therapy is recommended only if no response or unsatisfactory response to steroids. |
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219. A study by the North Florida Pterygium Study Group of postoperative beta-ray radiation therapy in patients with pterygium showed a recurrence rate of what percentage? A. < 2% B. 8% C. 15% D. 25% |
Answer 219 is A. Recurrence is rare after low-dose postoperative radiation. (IJROBP 28:101- 103, 1994). |
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220. Which of the following methods is used the most in diagnosing uveal melanoma? A. Clinical evaluation B. Needle biopsy C. Surgical excision D. CT scan |
Answer 220 is A. Most uveal melanomas are diagnosed clinically by experienced ophthalmologists with indirect ophthalmoscopy and ancillary procedures. Biopsy is not usually done. |
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6. Which of the following types of cancer was associated with a statistically significant improvement in survival for patients who had one to three solitary brain metastases and received whole brain radiation therapy with the addition of stereotactic radiosurgery, according to results of the RTOG 9508 phase III trial? A. Breast cancer B. Renal cell cancer C. Non-small cell lung cancer D. Melanoma |
Correct answer is C. RATIONALE: Based on the RTOG 9508 phase III trial results, patients with non-small cell lung cancer (NSCLC)/small cell cancer (SCC) had improved median survival with the addition of stereotactic radiosurgery (SRS) to whole brain radiation therapy (WBRT) on subset analysis. This is the basis for the ongoing RTOG 0320 phase III trial. |
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18. Which of the following neurological cognitive tests is most appropriate for measuring a patient's memory? A. Hopkins Verbal Learning Test (HVLT) B. Controlled Oral Word Association (COWA) Test C. Trail Making Test, Part A D. Grooved Pegboard Test |
Correct answer is A. RATIONALE: Memory is measured by the Hopkins Verbal Learning Test (HVLT). |
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26. Which of the following laboratory tests is most appropriate for determining if a patient with acromegaly has responded favorably to radiation therapy? A. Serum glucose level B. Growth hormone (GH) C. Thyroid stimulating hormone (TSH) D. Insulin-like growth factor-1 (IGF-1) |
Correct answer is D. RATIONALE: Insulin-like growth factor-1 (IGF-1) is a better test than growth hormone (GH). |
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30. Which of the following survival times is most likely to be associated with a patient who has a class II brain metastasis, based on the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA)? A. 10.2 months B. 07.1 months C. 04.2 months D. 02.3 months |
Correct answer is C. RATIONALE: Based on the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) for brain metastases, 4.2 months is the correct answer. |
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45. Which of the following PIV/TV ratios (conformality indexes) would be most appropriate when using conformal stereotactic radiosurgery to treat a patient with meningioma, according to the RTOG 9005 trial treatment parameters? A. 1.5 B. 2.5 C. 3.5 D. 4.5 |
Correct answer is A. RATIONALE: Extrapolating from the treatment parameters used in the RTOG 9005 trial, the PIV/TV ratio should be <2.0 to minimize complications. |
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55. Which of the following pathological findings is associated with patients who have meningioma? A. Verocay bodies B. Psammoma bodies C. Small, round blue cells D. Flexner-Wintersteiner rosettes |
Correct answer is B. RATIONALE: Psammoma bodies are associated with meningiomas. |
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69. Which of the following radiation doses per fraction would be most appropriate for a patient with malignant meningioma? A. 45 Gy/25 fractions B. 50.4 Gy/28 fractions C. 54 Gy/30 fractions D. 59.4 Gy/33 fractions |
Correct answer is D. RATIONALE: Since this is a malignant tumor, a radiation dose of 59.4 Gy would be appropriate. |
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83. Which of the following radiation doses should NOT be exceeded when stereotactic radiosurgery is administered to the optic chiasm? A. 04 Gy B. 06 Gy C. 08 Gy D. 14 Gy |
Correct answer is C. RATIONALE: A radiation dose of 8 Gy is the recommended upper limit (14 Gy is too high). |
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108. Which of the following statements about the management of brain metastases secondary to breast cancer is true? A. Prednisone therapy should be initiated with a loading dose of 20 mg, followed by 10 mg four times daily. B. Symptomatic improvement is expected between 24 to 72 hours after initiation of therapy. C. Treatment is more effective for focal neurological deficits than for headaches. D. Dexamethasone must be administered four times daily because of its half-life properties. |
Correct answer is B. RATIONALE: Corticosteroids are associated with multiple side effects including myopathy, weight gain, fluid retention, hyperglycemia, insomnia, gastritis, and immunosuppression. The frequency and severity of these symptoms can be modified by using the lowest dose possible. Most patients are started on dexamethasone because of relatively little corticosteroid, decreasing the risk of fluid retention and providing a lower risk of infection and cognitive impairment. A loading dose of 10 mg is given with 4 mg qid. Dexamethasone is given in 4 divided doses, but its biologic half-life could allow bid administration. References: Harris, JR. Diseases of the Breast. 3rd edition. Lippincott, Williams and Wilkins, 2004; pp 1207-1208. Vecht, CJ, et al (Wiley R, ed). Use of glucosteroids in neuron-oncology. Neurological Complications of Cancer. 1995; New York. Marcel Dekker. |
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109. What percent of pituitary adenomas are secretory tumors? A. 10% B. 30% C. 45% D. 65% |
Correct answer is D. RATIONALE: As many as 70% of pituitary adenomas are endocrinologically active, and the presence of a hypersecretory state is the most common mode of presentation. |
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121. Which of the following pathologic subtypes is most commonly associated with diffuse astrocytoma in adults? A. Pilocytic B. Fibrillary C. Protoplasmic D. Gemistocytic |
Correct answer is B. RATIONALE: Fibrillary astrocytoma is the most common subtype. |
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142. What is the most common genetic abnormality associated with low-grade gliomas? A. 1p B. 10q C. 17p D. 19q |
Correct answer is C. RATIONALE: Deletion of chromosome 17p contains the p53 gene. |
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151. Which of the following statements about brain metastases secondary to breast cancer is true? A. Breast cancer is the most common cause of brain metastases in women. B. HER-2/neu gene overexpression is not associated with an increased risk of brain metastases. C. Increased tumor size and number of positive lymph nodes are associated with an increased risk of brain metastases. D. Brain metastases are most likely to involve a solitary site. |
THIS ITEM WAS PARTIALLY SCORED (BOTH OPTIONS C & D SCORED CORRECT). RATIONALE: The most common cause of brain metastases in women is lung cancer. Breast cancer is the second leading cause. In patients who have breast cancer and are screened for enrollment in clinical trials of systemic therapy, 14.8% of patients had clinically occult CNS metastases. Of these patients, tumors with HER-2/neu gene overexpression and the number of metastatic sites were significant predictors for CNS involvement by multivariate analysis. Breast cancer rarely presents with brain metastases before detection of the primary cancer. Brain metastases are more likely to present in premenopausal women with aggressive, widely metastatic disease. There is no relationship among the size, site of the primary tumor or the number of positive lymph nodes, and the subsequent development of brain metastases. ER-negative tumors are more likely to metastasize to the brain than are ER-positive tumors. References: Harris, JR. Diseases of the Breast, 3rd edition, Lippincott, Williams and Wilkins, 2004; pp 1205-1218. Miller, K, et al. Occult central nervous system involvement in patients with metastatic breast cancer: prevalence, predictive factors and impact on overall survival. Annals of Oncology. 2003;4:1972-1977. Sparrow, GE, et al. Brain metastases from breast cancer: clinical course, prognosis and influence of treatment. Clinical Oncology. 1981;7:291-301. Stewart, JF, et al. Estrogen receptors, sites of metastatic disease and survival in recurrent breast cancer. European Journal of Cancer. 1981;17:449-453. |
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152. Which of the following types of astrocytoma is associated with tuberous sclerosis? A. Fibrillary B. Gemistocytic C. Protoplasmic D. Subependymal giant cell |
Correct answer is D. RATIONALE: Subependymal giant cell astrocytomas occur in 5% of patients with tuberous sclerosis. |
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163. Which of the following factors is most important in establishing a favorable prognosis for a child with posterior fossa ependymoma? A. Excellent response to induction chemotherapy B. Achievement of a gross total resection C. Absence of p53 gene deletion D. Patient age >8 years |
Correct answer is B. RATIONALE: The extent of surgical resection has been the single most important prognostic factor in patients over 18 months of age. (St. Jude, CCG). |
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167. Which of the following statements about leptomeningeal metastases secondary to breast cancer is true? A. A headache is the most common symptom in patients at presentation. B. A contrast-enhanced CT scan is best for establishing the diagnosis. C. Radiation therapy should be administered to the entire CNS axis. D. The median survival rate is 4 months, but longer survival times are associated with breast cancer. |
Correct answer is D. RATIONALE: Spinal symptoms are the most common presentation of leptomeningeal disease. Limb weakness with paresthesias and pain occur in the affected limb. Headaches are the most common symptom of cerebral disease. Diplopia is the most common cranial nerve symptom. Gadolinium-enhanced MRI is the modality of choice for both cranial and spinal sites. CT is less sensitive and is not useful for spinal imaging unless a contrast agent is used in the subarachnoid space. Radiation therapy should be given to symptomatic areas and to sites of bulky disease. Radiation is the best treatment for focal leptomeningeal nodules. Focal radiation can help restore normal CNS flow and facilitate effectiveness of intrathecal therapies. Reference: Harris, JR. Diseases of the Breast. 3rd edition. Lippincott, Williams & Wilkins, 2004; pp 1231-1240. |
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168. Oligodendrogliomas most commonly exhibit which of the following types of pathological pattern? A. Necrosis B. Fried egg appearance C. Rosenthal fibers D. Globoid cells |
Correct answer is B. RATIONALE: The “fried egg appearance” is secondary to prominent nuclei surrounded by a cytoplasmic halo. |
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179. What is the most appropriate therapy for a 6-year-old child with a completely resected medulloblastoma with no evidence of metastasis? A. Craniospinal irradiation to a dose of 23.4 Gy and 55.8-Gy boost dose to the posterior fossa B. Concurrent chemotherapy with craniospinal irradiation to 23.4 Gy and 55.8-Gy boost dose to the posterior fossa, followed by additional chemotherapy C. Concurrent chemotherapy with craniospinal irradiation to 36 Gy and 55.8-Gy boost dose to the posterior fossa, followed by additional chemotherapy D. Induction chemotherapy, craniospinal irradiation to a dose of 36 Gy and 55.8-Gy boost dose to the posterior fossa, followed by additional chemotherapy |
Correct answer is B. RATIONALE: Standard of care in North America currently is concurrent Vincristine with craniospinal irradiation (CSI) to a dose of 23.4 Gy and a boost to the posterior fossa followed by additional chemotherapy for standard risk patients. This question is asking the examinee about risk groups (standard versus high risk) and the appropriate treatment of standard-risk patients. |
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184. What is the minimum percentage of oligodendroglioma cells required for a tumor to be classified as a mixed oligoastrocytoma? A. 05% B. 15% C. 25% D. 50% |
Correct answer is C. RATIONALE: For a tumor to be classified as a mixed oligoastrocytoma, at least 25% of the tumor has to consist of oligodendroglioma cells. |
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193. Which of the following tumors is LEAST likely to be treated with craniospinal irradiation? A. Pineoblastoma B. Ependymoblastoma C. Nongerminomatous germ cell tumor D. Pure germinoma |
Correct answer is D. RATIONALE: Pure germinomas have the lowest risk for dissemination to the spine and can be treated with whole ventricular irradiation only. The other tumors have a much higher risk of spread through the cerebrospinal fluid (CSF), requiring craniospinal axis irradiation. |
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195. Prescriptions for radiosurgery are made to what percent of maximum dose for the listed modalities? Gamma Knife Linac Beam A. 100% 100% B. 080% 050% C. 050% 080% D. 050% 050% |
Correct answer is C. RATIONALE: The cobalt Gamma Knife sources provide a wider penumbra than the sharply collimated linac beams. |
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200. Which of the following MRI sequences and margins would be most appropriate for target delineation of a low-grade oligodendroglioma? A. T1 + 1.5 cm B. T1 + 3 cm C. T2 + 2 cm D. FLAIR + 3 cm |
Correct answer is C. RATIONALE: The MRI sequence and margin T2 + 2 cm are the most appropriate for delineation of a low-grade oligodendroglioma that has been used in the RTOG trials. |
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187. Which of the following tests should be included in the workup of a 3-year-old child who has a presumed diagnosis of stage 3, high-risk abdominal neuroblastoma? A. MRI of the brain B. Cerebrospinal fluid cytology C. Total body gallium scan D. Urinary catecholamine metabolite levels |
Correct answer is D. RATIONALE: This patient should have measurements of urine vanillylmandelic acid (VMA) and homovanillic acid (HVA) levels, which are catecholamine metabolites. |
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206. Which of the following eye tumors should be diagnosed clinically without a biopsy? A. Retinoblastoma B. Orbital rhabdomyosarcoma C. Conjunctival lymphoma D. Pseudolymphoma |
Correct answer is A. RATIONALE: A biopsy of retinoblastoma can result in vitreous seeding. |
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207. Which of the following statements about CNS germinomas is true? A. The suprasellar region is the most common site of origin. B. They most commonly occur during the second and third decade of life. C. The best treatment is craniospinal axis irradiation, followed by a boost dose to the primary tumor. D. Alpha-fetoprotein serum levels are elevated in patients with pure germinoma. |
Correct answer is B. RATIONALE: Patients with CNS germinomas most commonly present in their 2nd decade of life. The pineal region is the most common site of origin. Because the predominant risk for its dissemination is in the ventricles, patients can be treated with whole ventricle radiation therapy, followed by primary tumor boost avoiding full craniospinal axis irradiation. Beta-HCG can sometimes be slightly elevated in patients with pure germinoma, but elevated alpha-fetoprotein serum levels will exclude that diagnosis. |
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223. Which of the following statements about brainstem gliomas is true? A. High-grade tumors display exophytic growth. B. The majority of tumors are low-grade gliomas. C. Radiation doses greater than 54 Gy have not been shown to improve survival. D. The addition of chemotherapy has improved overall survival rates. |
Correct answer is C. RATIONALE: The majority of brainstem tumors are high-grade although the exact grade distribution is difficult due to the lack of biopsy information. High-grade tumors mostly demonstrate intrinsic growth into the brainstem. The POG randomized trial of conventional vs. hyperfractionated high-dose irradiation failed to show any benefit from radiation dose escalation. There has been no benefit shown from the addition of chemotherapy for brainstem gliomas. |
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228. Which of the following statements about uveal melanomas is true? A. Systemic metastases are the cause of death in the majority of patients. B. A biopsy is necessary to establish the diagnosis in the majority of patients. C. Preoperative radiation therapy does not improve local control in patients with large tumors. D. Enucleation produces better overall survival than plaque brachytherapy in patients with medium-sized tumors. |
Correct answer is C. RATIONALE: COMS showed that both enucleation and plaque brachytherapy produces the same overall survival outcome. Preoperative radiation therapy before enucleation does not produce better local control compared to enucleation alone. |
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246. What structure in the eye is most radioresistant to late injury? A. Lens B. Retina C. Lacrimal gland D. Sclera |
Correct answer is D. RATIONALE: The sclera is most radioresistant, and the lens of the eye is the most radiosensitive of the structures described. |
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254. Which of the following statements about temporal bone chemodectomas is true? A. They are derived from neural crest tissue of the second branchial arch associated with either cranial nerve IX or X. B. Microscopic evaluation of these tumors reveals a high level of disorganization of cellular alignment. C. The majority occur in the inferior tympanic canaliculus. D. They are very sensitive to chemotherapy. |
Correct answer is A. RATIONALE: Chemodectomas look histologically benign and are sensitive to radiation therapy, but not to chemotherapy. Only 20% of temporal bone chemodectomas occur in the inferior tympanic canaliculus. |
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266. Which of the following statements about ependymomas is true? A. Patient survival is dependent on the degree of tumor resection. B. They most commonly occur in patients older than 21 years of age. C. Approximately 30% of patients with ependymomas have cerebrospinal fluid dissemination. D. Postoperative radiation therapy has no impact on local control in completely resected tumors. |
Correct answer is A. RATIONALE: Ependymoma most commonly affects children younger than 5 years of age. The risk of cerebrospinal fluid (CSF) spread is approximately 5% to 10%. Completeness of tumor resection affects patient survival, and the postoperative radiation therapy dose impacts disease control (see Perez textbook). |
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272. Which of the following statements about the role of radiation therapy in the management of paragangliomas is true? A. Surgery followed by radiation therapy is the preferred treatment. B. The radiation dose response increases above 45 Gy for tumor regression. C. The local control rate after radiation doses of 45 Gy alone is commonly 90% to 95%. D. Compared to radiation therapy, surgery offers improved control and disease-specific survival rates. |
Correct answer is C. RATIONALE: Surgery or radiation therapy can be used to treat paragangliomas. A radiation dose of 45 Gy is sufficient to achieve excellent local control (>90%). |
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284. Which of the following prognostic factors is included in the Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA)? A. Tumor size B. Tumor stage C. Mental status D. Extent of resection |
Correct answer is C. RATIONALE: RTOG recursive partitioning analysis included the following prognostic factors: patient's age, Karnofsky performance status, duration of neurologic symptoms, mental status. |
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292. Which of the following neurological complications is most common after surgical resection of paragangliomas? A. Superior laryngeal nerve paralysis B. Spinal accessory nerve injury C. Hypogossal nerve injury D. Vagus nerve injury |
Correct answer is D. RATIONALE: Injury to cranial nerves IX and X are the most common neurological complications after surgical resection of paragangliomas. |
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293. Which of the following radiation doses is LEAST preferred for prophylactic cranial irradiation administered to patients who have limited-stage small cell lung cancer and who experience a complete response to chemotherapy for their lung lesions? A. 24 Gy in 8 fractions B. 25 Gy in 10 fractions C. 30 Gy in 10 fractions D. 30 Gy in 15 fractions |
Correct answer is C. Reference: Journal of the National Comprehensive Cancer Network (JNCCN). 2006;4:619. |
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304. Which of the following statements about craniopharyngiomas is true? A. Complete surgical resection is possible in approximately 10% to 15% of patients. B. Surgery is rarely associated with visual and endocrine complications. C. Conformal external-beam radiation therapy of 40 Gy delivered to both cystic and solid components with a 0.5-cm margin will achieve local control. D. Intracavitary diluted β-emitter isotopes can be used to treat cystic lesions with up to 200 Gy prescribed to the cyst wall. |
Correct answer is D. RATIONALE: The recommended dose for external-beam radiation therapy is about 54 to 55 Gy. P-32, a beta-emitter, can be used to treat monocystic lesions. |
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20. Which of the following MRI sequences should be used to define the target volume for a patient who will undergo radiation therapy for an oligodendroglioma? A. Diffusion-weighted B. T1-weighted without contrast C. T1-weighted with contrast D. T2-weighted |
Correct answer is D. RATIONALE: The T2-weighted MRI sequence is used to define tumor volume, based on the trial by the Radiation Therapy Oncology Group (RTOG). Oligodendroglioma does not usually enhance with contrast, and the best way to delineate this tumor consistently is with T2-weighted MRI sequences. |
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60. According to RTOG criteria, what is the minimum percent of oligodendroglioma component required for a tumor to be classified as an oligoastrocytoma? A. 10% B. 25% C. 50% D. 75% |
Correct answer is B. RATIONALE: The minimum percent of oligodendroglioma component is 25%, based on the Radiation Therapy Oncology Group (RTOG) criteria. |
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67. Which of the following statements about CNS-related atypical teratoid/rhabdoid tumors (AT/RT) is true? A. It has the same prognosis as medulloblastoma. B. The median age of diagnosis is less than 1 year. C. Standard treatment involves postoperative involved-field radiation therapy alone. D. Leptomeningeal spread rarely occurs in patients with AT/RT. |
Correct answer is B. RATIONALE: Atypical teratoid/rhabdoid (AT/RT) tumors carry a much worse prognosis than medulloblastoma. The standard treatment typically involves surgery, multiagent chemotherapy, +/- involved-field or craniospinal irradiation. Leptomeningeal spread is common in AT/RT. |
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75. Which of the following tumor types in an adult has the highest response rate to chemotherapy? A. Glioblastoma multiforme, WHO grade IV B. Anaplastic oligodendroglioma, 1p and 19q codeleted C. Anaplastic oligodendroglioma, 1p and 19q intact D. Anaplastic astrocytoma, WHO grade III |
Correct answer is B. RATIONALE: 1p and 19q codeletion predicts for a high response rate to chemotherapy in patients with malignant gliomas and is most commonly seen in patients with anaplastic oligodendrogliomas. Clinical trials are currently underway evaluating the role of radiation in this molecular subtype after a favorable response to chemotherapy. |
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86. According to a randomized trial, what has been shown to improve overall survival in patients who have glioblastoma multiforme and received 60 Gy of external-beam radiation therapy? A. Brachytherapy implant B. IMRT boost dose to 90 Gy C. Radiosurgery boost dose to T1 residual abnormality D. Concurrent and adjuvant temozolomide |
Correct answer is D. RATIONALE: Shipp, et al, performed a randomized European Organization for Research and Treatment of Cancer (EORTC) study evaluating radiation therapy with concomitant and adjuvant temozolomide versus radiation therapy alone. The final results published in the New England Journal of Medicine revealed improved overall and event free survival in patients with glioblastoma multiforme. |
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25. Which of the following is a favorable prognostic factor for oligodendroglioma? (A) Solitary 19q loss (B) Higher radiation dose (C) Seizures as a presenting symptom (D) Presence of contrast enhancement |
Key: C References: Chaichana KL, McGirt MJ, Niranjan A, Olivi A, Burger PC, Quinones-Hinojosa A. Prognostic significance of contrast-enhancing low-grade gliomas in adults and a review of the literature.Neurol Res. 2009 Nov; 31(9):931-9. Epub 2009 Feb 12. Scheie D, Meling TR, Cvancarova M, Skullerud K, Mørk S, Lote K, Eide TJ, Helseth E, Beiske K.Prognostic variables in oligodendroglial tumors: a single-institution study of 95 cases.Neuro Oncol. 2011 Nov; 13(11):1225-33. Epub 2011 Aug 19. Karim AB, Maat B, Hatlevoll R, Menten J, Rutten EH, Thomas DG, Mascarenhas F, Horiot JC, Parvinen LM, van Reijn M, Jager JJ, Fabrini MG, van Alphen AM, Hamers HP, Gaspar L, Noordman E, Pierart M, van Glabbeke M. A randomized trial on dose-response in radiation therapy of low-grade cerebral glioma: European Organization for Research and Treatment of Cancer (EORTC) Study 22844. Int J Radiat Oncol Biol Phys. 1996 Oct 1; 36(3):549-56. Shaw E, Arusell R, Scheithauer B, O'Fallon J, O'Neill B, Dinapoli R, Nelson D, Earle J, Jones C, Cascino T, Nichols D, Ivnik R, Hellman R, Curran W, Abrams R. Prospective randomized trial of low- versus high-dose radiation therapy in adults with supratentorial low-grade glioma: initial report of a North Central Cancer Treatment Group/Radiation Therapy Oncology Group/Eastern Cooperative Oncology Group study.J Clin Oncol. 2002 May 1; 20(9):2267-76. |
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90. Which of the following hormones is LEAST commonly affected in children receiving cranial irradiation? A. Thyroid-stimulating hormone B. Follicle-stimulating hormone C. Growth hormone D. Vasopressin |
Correct answer is D. RATIONALE: Deficiency of Vasopressin leading to diabetes insipidus is rarely caused by irradiation. It is more likely to be the result of surgery in the region of the pituitary gland. |
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107. The prognosis for a patient with low-grade astrocytoma worsens at what age cutoff? A. 40 years B. 50 years C. 60 years D. 65 years |
Correct answer is A. RATIONALE: Patients older than 40 years of age do worse, based on the North Central Cancer Treatment Group (NCCTG), Radiation Therapy Oncology Group (RTOG), and European Organization for Research and Treatment of Cancer (EORTC) data. |
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159. Which of the following tumor types has the highest risk for cerebrospinal fluid dissemination if the entire craniospinal axis is NOT treated with radiation? A. Pineocytoma B. Pineoblastoma C. Pineal germinoma D. Pineal non-seminomatous germ cell tumor |
Correct answer is B. RATIONALE: A retrospective study by Schild, et al, in the Mayo clinic defined pineoblastoma as having the highest risk of cerebrospinal fluid (CSF) dissemination among the tumor types listed. Reference: Schild, et al. Cancer. 1996;78:2561-2571. |
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174. Based on the EORTC trial, what is the progression-free survival rate at 5 years for a patient who has a low-grade astrocytoma and underwent observation? A. 15% B. 35% C. 55% D. 75% |
Correct answer is B. RATIONALE: The progression-free survival rate is 35% at 5 years for a patient with a low-grade astrocytoma, based on a European Organization for Research and Treatment of Cancer (EORTC) trial. |
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182. According to results of the RTOG 9508, phase III trial that compared the use of whole-brain radiation therapy alone (WBRT) versus WBRT and radiosurgery, the median survival time for a patient with a single-brain metastasis undergoing WBRT and radiosurgery was: A. 4.5 months. B. 6.5 months. C. 9.0 months. D. 12.0 months. |
Correct answer is B. RATIONALE: The median survival for a patient with a single-brain metastasis treated with whole-brain radiation therapy (WBRT) and stereotactic radiosurgery (SRS) is 6.5 months, based on the Radiation Therapy Oncology Group (RTOG) 9508 trial. |
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190. What is the most common serious complication from surface 90Sr for pterygium? A. Secondary malignancy B. Corneal ulceration C. Retinal injury D. Cataract |
Correct answer is B. RATIONALE: Corneal ulceration occurs in less than 5% of patients receiving postoperative 90Sr for pterygium, but it is a serious complication that should be discussed with patients. |
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203. MGMT gene methylation status is associated with the prognosis of patients with which of the following tumor types? A. Diffuse astrocytoma B. Pilocytic astrocytoma C. Anaplastic oligodendroglioma D. Glioblastoma multiforme |
Correct answer is D. RATIONALE: MGMT gene methylation status in patients with glioblastoma multiforme (GBM) predicts overall survival after treatment with temozolomide and radiation therapy. Other types of glioma may have a gene methylation promoter, but the data supporting the prognostic impact of this marker is most established for patients with GBM. Reference: Clinical Cancer Research. 2004;10:1871-1874. |
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221. Which of the following conditions is associated with the development of meningioma? A. Tuberous sclerosis B. Neurofibromatosis type 2 C. Sturge-Weber syndrome D. von Hippel-Lindau disease |
Correct answer is B. RATIONALE: While 90% of patients with neurofibromatosis type 2 (NF2) have acoustic schwannomas, >50% develop tumors of other cranial nerves and meningiomas. The other conditions are not associated with meningioma development. |
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227. The most common endocrine abnormality that occurs after resection of a craniopharyngioma is: A. SIADH. B. growth hormone deficiency. C. diabetes insipidus. D. hypothyroidism. |
Correct answer is C. RATIONALE: Approximately 70% to 90% of patients have diabetes insipidus after surgery for craniopharyngioma. Not all patients require permanent replacement with Desmopressin acetate (DDAVP), a synthetic analogue of the natural pituitary antidiuretic hormone (ADH), but it is important to recognize this common problem in the perioperative period. |
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230. Which of the following hormones is most commonly affected in children receiving cranial irradiation? A. Thyroid-stimulating hormone B. Follicle-stimulating hormone C. Growth hormone D. Vasopressin |
Correct answer is C. RATIONALE: Growth hormone is the most radiosensitive hormone, followed by thyroid-stimulating hormone (TSH) and follicle-stimulating hormone (FSH). Vasopressin is rarely affected by irradiation. |
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275. Which of the following two therapies were evaluated by the Collaborative Ocular Melanoma Study (COMS) for patients with medium-sized choroidal melanoma? A. 125I plaque brachytherapy versus enucleation B. 125I plaque brachytherapy versus intraocular chemotherapy C. 137Cs plaque brachytherapy versus external-beam radiation therapy D. External-beam radiation therapy versus enucleation |
Correct answer is A. RATIONALE: The Collaborative Ocular Melanoma study (COMS) randomized patients with choroidal melanomas measuring 2.5 to 10.0 mm in apical height and <16.0 mm maximal basal diameter to enucleation vs 125I plaque brachytherapy. The results thus far have shown equivalent local control and 12-year survival. |
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279. Which of the following statements about diffuse pontine glioma is true? A. It has the worst prognosis of all brainstem gliomas. B. Radiation-dose escalation improves the outcome. C. The incidence of CNS dissemination is 75%. D. Biopsy is recommended for diagnosis. |
Correct answer is A. RATIONALE: Benefits with dose escalation have not been demonstrated in a phase III Pediatric Oncology Group trial comparing 54 Gy and 70.2 Gy. Brainstem gliomas rarely disseminate. Diffuse pontine gliomas (DPG) are usually treated without a biopsy and diagnosed by a characteristic appearance on radiographic evaluation. Patients with DPG have a median overall survival of less than 1 year. |
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280. The best medical therapy for a patient with acromegaly is: A. mitotane. B. somatostatin. C. bromocriptine. D. metapyrone. |
Correct answer is B. RATIONALE: Somatostatin inhibits IGF1, which is overproduced in patients with acromegaly. The other therapies are used for non-GH-secreting pituitary tumors. |
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290. What is the most common neoplasm diagnosed after cranial irradiation? A. Meningioma B. Pilocytic astrocytoma C. Pleomorphic xanthoastrocytoma D. Acoustic schwannoma |
Correct answer is A. RATIONALE: A large retrospective study reviewing Israeli children treated for tinea capitis with low-dose cranial irradiation revealed a higher than expected incidence of brain tumors, with the most frequent brain tumor being meningioma. |
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298. What is the most common type of primary brain neoplasm in the United States? A. Acoustic schwannoma B. Juvenile pilocytic astrocytoma C. Glioblastoma D. Meningioma |
Correct answer is D. RATIONALE: According to the Surveillance Epidemiology and End Results (SEER) database, meningiomas were diagnosed in 10,000 patients and glioblastoma in 8,967 patients between 1992 and 1997. Meningioma and glioblastoma are two leading primary brain neoplasms in the United States. |
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337. A response to induction chemotherapy may allow a lower radiation dose and smaller radiation volume for which of the following tumor types? A. Anaplastic oligodendroglioma B. Pilocytic astrocytoma C. Pineal germinoma D. CNS lymphoma |
Correct answer is C. RATIONALE: Although all of the tumors listed may respond to chemotherapy, a treatment strategy of reduced dose and volume radiation therapy (RT) has been most commonly studied in CNS germ cell tumors. Selected patients responding to systemic chemotherapy may receive less craniospinal RT (i.e., doses that are 30 to 45 Gy instead of greater than 50 Gy). |
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345. What distance from the optic apparatus to a pituitary adenoma usually is required for optimal dosing of a patient who has acromegaly and is to undergo radiosurgery? A. 2 mm B. 5 mm C. 8 mm D. 10 mm |
Correct answer is B. RATIONALE: Based on stereotactic radiosurgery (SRS) literature, 5 mm is considered ideal. With most stereotactic radiosurgery (SRS) dose gradients, 5 mm is found to be the minimal distance between the optic chiasm and the tumor to provide an acceptable dose to the chiasm while adequately treating the tumor. |
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351. A 10-year-old patient has a large, mixed cystic/solid craniopharyngioma with compression of the optic chiasm and involvement of the hypothalamus. Appropriate treatment should consist of: A. neoadjuvant chemotherapy, followed by surgery. B. surgical cyst decompression with intracystic 32P. C. aggressive surgery with resection of all visible disease. D. conservative surgery, followed by external-beam radiation therapy. |
Correct answer is D. RATIONALE: Conservative surgery followed by external-beam radiation therapy yields equivalent local results to radical surgery with a lower rate of hypothalamic injury. No randomized trials have taken place; however, retrospective analysis from St. Jude’s supports this multi-modality treatment approach for the optimal long-term outcomes for tumor control and neurocognitive outcomes. |
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358. Based on the RTOG recursive partitioning analysis, the most important determinant for survival of a patient with brain metastases is the: A. KPS. B. type of tumor. C. age of the patient. D. evidence of extracranial disease. |
Correct answer is A. RATIONALE: KPS is the most important factor based on Radiation Therapy Oncology Group (RTOG) recursive partitioning analysis (RPA) for brain metastases. |
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35. Which of the following recursive partitioning analysis (RPA) classifications and primary disease sites had an overall survival benefit based on the phase III RTOG 9508 (Andrews) trial that evaluated WBRT with and without stereotactic radiosurgery? RPA Primary Disease Site A. Class I Lung cancer B. Class III Lung cancer C. Class I Breast cancer D. Class III Breast cancer |
Correct answer is A. RATIONALE: Based on the subgroup analysis of RPA classification and primary disease site, patients who had lung cancer and were in the RPA class I group experienced an overall survival benefit with the addition of stereotactic radiosurgery (SRS) to WBRT. Otherwise, no detectable overall survival advantage was demonstrated with the addition of SRS to WBRT. |
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47. Which of the following tests would most reliably confirm the cause of MRI enhancement in the treatment field 6 months after a patient with glioblastoma has completed chemoradiation? A. 18FDG PET scan B. MR spectroscopy C. Diffusion-weighted MRI D. Biopsy |
Correct answer is D. RATIONALE: Although all of the tests may suggest tumor progression versus treatment effect, none replace a stereotactic or open biopsy. |
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49. What is the cumulative incidence of secondary cancers in patients who receive EBRT for hereditary retinoblastoma? A. 00% to 5% B. 10% to 15% C. 35% to 40% D. 70% to 75% |
Correct answer is C. RATIONALE: Patients with hereditary retinoblastoma who received external-beam radiation therapy (EBRT) have a 35% cumulative incidence of secondary cancers. A child with unilateral retinoblastoma who presents with advanced intraocular disease and undergoes enucleation has a cure rate of >95%. REFERENCE: Chintagumpala, et al. The Oncologist. October 2007;12(10):1237-1246. |
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57. Which of the following radiation therapy methods for dose escalation has NOT been tested in a randomized phase III trial for treatment of malignant glioma? A. Radiosurgery B. Brachytherapy C. Fast neutron D. Proton |
Correct answer is D. RATIONALE: Proton radiation therapy for dose escalation has not been tested in a randomized trial. Multi-institutional randomized trials have been performed for radiosurgery, brachytherapy, and fast neutrons without showing a survival benefit. |
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59. Which of the following statements about brain metastases secondary to breast cancer is true? A. The overall incidence is 15%. B. The most common symptoms are acute onset of headaches, nausea, and vomiting. C. Lung, liver, or lymph node metastases predict a higher risk for development of brain metastases. D. Age does not affect the risk for development of brain metastases. |
Correct answer is C. RATIONALE: The incidence of brain metastases is 5%. The most common finding associated with the onset of brain metastases is a slowly progressive neurological deficit. Seizures and acute stroke or TIA-like symptoms also can be seen. A higher risk of brain metastases is seen in patients who are under 40 years of age; have HER-2-positive disease; and have ER-negative disease. REFERENCE: Kaal ECA and Vecht C. CNS complications of breast cancer: current and emerging treatment options. CNS Drugs. 2007;21(7):559-579. |
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64. Which of the following treatments would be most appropriate for an 8-year-old boy with nondisseminated unifocal pure germinoma of the pineal area? A. Four cycles of etoposide and cisplatin alone B. Radiation therapy to the primary tumor alone C. Whole-ventricular radiation therapy, followed by a boost dose to the primary tumor D. Complete surgical resection, followed by radiation therapy to the primary tumor |
Correct answer is C. RATIONALE: Involved-field radiation therapy alone is regarded as inadequate therapy for focal CNS germinoma with or without complete surgical resection. Omission of consolidative radiation therapy (RT) after chemotherapy will result in a high risk of disease recurrence. Although the treatment volume for focal CNS germinoma has been vigorously debated, a recent systematic review from Lancet Oncology (2005) by Rogers, et al. showed that whole-brain or whole-ventricular RT followed by a boost yielded identical rates of local control, neuraxis control, and survival compared to craniospinal RT followed by a boost in adequately staged patients. REFERENCE: Rogers SJ, Mosleh-Shirazi MA, and Saran FH. Radiotherapy of localized intracranial germinoma: time to sever historical ties? Lancet Oncology. 2005;6(7):509-519. |
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84. Which of the following factors is most important in determining the prognosis of patients with intracranial ependymoma? A. Sex of the patient B. Extent of resection C. Location of the tumor D. Use of chemotherapy |
Correct answer is B. RATIONALE: Among the factors listed above, the extent of resection is the most important prognostic factor. The use of chemotherapy has not been consistently shown to impact survival or tumor control. REFERENCE: Merchant TE. Current management of childhood ependymoma. Oncology. Williston Park; May 2002;16(5):629-42, 644. |
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87. Which of the following types of benign meningioma should NOT be treated with stereotactic radiosurgery? A. Optic nerve sheath B. Skull base C. Convexity D. Parasagittal |
Correct answer is A. RATIONALE: Radiosurgery should not be performed for optic nerve sheath tumors given the risk for optic neuropathy. |
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103. Which of the following factors is NOT prognostic for patients with medulloblastoma? A. Stage B. Extent of resection C. Age younger than 3 years D. Location of tumor |
Correct answer is D. RATIONALE: The specific location of the primary tumor does not appear to have prognostic implication, though tumors in the cerebellar hemisphere tend to occur in older patients. The other factors have a clear effect on prognosis. |
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148. What percent of pituitary adenomas are secretory tumors? A. 10% B. 30% C. 50% D. 70% |
Correct answer is D. RATIONALE: The majority of pituitary adenomas (70%) are secretory. |
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152. Loss of heterozygosity of chromosomes 1p/19q in patients with oligodendroglioma does NOT predict which of the following outcomes? A. Radiographic response to chemotherapy B. Overall survival after radiation therapy alone C. Overall survival after chemotherapy alone D. Tumor resectability |
Correct answer is D. RATIONALE: 1p/19q LOH predicts better response and survival after both chemotherapy and radiation therapy. The ability to completely resect a tumor is not predicted by 1p/19q status. |
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200. Which of the following types of tumor is most often associated with EGFR amplification? A. Anaplastic oligodendroglioma B. Low-grade glioma C. De novo glioblastoma D. Ependymoma |
Correct answer is C. RATIONALE: EGFR-based strategies are currently being employed in clinical trials for glioblastoma. EGFR amplification is noted in de novo glioblastoma, but not in those glioblastomas that arise from lower-grade neoplasms. These tumors appear to be molecularly distinct and may respond to different treatment strategies. |
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206. Which of the following diagnoses is most appropriate for a 16-year-old patient who has Parinaud's syndrome and an elevated serum α-fetoprotein level? A. Hepatoblastoma B. Pineal germ cell tumor C. Hypothalamic germinoma D. Choriocarcinoma |
Correct answer is B. RATIONALE: Parinaud's syndrome is an upward gaze palsy that can be caused by a pineal tumor. An elevated α-fetoprotein (AFP) level is suggestive of a germ cell tumor, particularly a non-germinomatous germ cell tumor. |
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209. What percent of patients diagnosed with primary ocular lymphoma will have CNS involvement within 1 year of diagnosis? A. 05% to 10% B. 20% to 30% C. 50% to 80% D. >90% |
Correct answer is C. RATIONALE: Fifty to eighty percent of patients with primary ocular lymphoma will have CNS involvement at a median rate of 9 months. Thus, radiation therapy must include the intracranial contents and both eyes to ensure coverage of high-risk areas. |
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212. A patient has anaplastic ependymoma with negative findings on CSF cytology and MRI of the spine. What is the risk of CNS dissemination after gross total resection, followed by radiation therapy to the primary site only? A. <5% B. 10% to 15% C. 30% to 40% D. 50% to 60% |
Correct answer is B. RATIONALE: Although anaplastic histology was once considered an indication for elective craniospinal radiation therapy (RT), the true risk of dissemination is very modest (~10-15%) if the primary site is treated locally. |
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215. Which of the following treatments would be most appropriate for a 50-year-old patient who has Graves' disease with significant bilateral ophthalmopathy and diplopia? A. 131I therapy B. 40 Gy of fractionated radiation therapy to the orbits C. 20 Gy of fractionated radiation therapy to the orbits D. Systemic iodine chelation with immunosuppressive therapy |
Correct answer is C. RATIONALE: Graves' ophthalmopathy can be treated with surgical decompression, steroid treatment, or low-dose fractionated radiation therapy (20 Gy in 10 to 20 fractions) with a reasonable symptomatic improvement. Four randomized trials with radiation therapy (RT) vs sham RT showed consistent marginal benefit. |
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217. Which of the following visual-field defects is typically found in patients with craniopharyngioma? A. Central scotoma B. Homonymous hemianopsia C. Bitemporal hemianopsia D. "Pie-in-the-sky" defect |
Correct answer is C. RATIONALE: Bitemporal hemianopsia is the most common visual-field deficit noted because of compression of the optic chiasm. |
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224. Which of the following childhood CNS tumors has the worst prognosis? A. Medulloblastoma B. Pilocytic astrocytoma C. Atypical teratoid rhabdoid tumor D. Pure germinoma |
Correct answer is C. RATIONALE: Atypical teratoid rhabdoid tumor carries the worst prognosis among the tumors listed with a 1-year survival rate of 50%. The other tumors have a 5-year survival rate in the range of 80-90%. |
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227. Which of the following statements about tumors of the temporal bone is true? A. Paraganglioma is most common. B. Cranial nerve VIII is most commonly involved when skin cancer invades into the temporal bone. C. Level 2 lymph node involvement is most common when tumors involve the external auditory canal. D. The most frequent symptoms of temporal bone paragangliomas are headaches and facial nerve palsy. |
Correct answer is A. RATIONALE: It is important to understand the spread pattern and common presentation of tumors in this area. The most frequent symptoms associated with temporal bone paragangliomas are hearing loss and tinnitus. |
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237. Which of the following findings on MR spectroscopy is most commonly associated with a low-grade astrocytoma? A. Low choline B. Low N-acetylaspartate C. High creatine D. High lactate |
Correct answer is B. RATIONALE: Patients with low-grade astrocytoma typically have low N-acetylaspartate (NAA), choline/creatine>1, and no lactate. |
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243. For a pediatric patient receiving craniospinal irradiation, the advantage of using electrons versus photons to treat the posterior spinal fields is to: A. provide improved coverage of the spine. B. minimize hot spots between the abutting cranial and spinal fields. C. minimize the exit dose. D. minimize the surface dose. |
Correct answer is C. RATIONALE: Compared to photons, electrons are less penetrating. As a result, the dose to structures anterior to the spine is considerably lower when electrons are used for spinal irradiation. |
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246. Which of the following complications most commonly occurs in patients receiving fractionated radiation therapy for pituitary adenomas? A. Vascular injury B. Optic neuropathy C. Radiation necrosis D. Endocrine dysfunction |
Correct answer is D. RATIONALE: The majority of patients with pituitary adenomas develop one or many endocrine deficiencies after undergoing radiation therapy. |
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276. What is the expected 5-year overall survival rate for a 5-year-old patient who has average-risk medulloblastoma treated with craniospinal irradiation and chemotherapy? A. 67% B. 70% C. 85% D. 93% |
Correct answer is C. RATIONALE: Children's cancer group study A9961 for average-risk medulloblastoma reported a 5-year-old child’s overall survival (OS) rate to be 86%, while a 5-year-old child's event-free survival (EFS) rate was reported to be 81%. |
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295. Which of the following subtypes of ependymoma has the lowest risk of recurrence after gross total resection alone? A. Thoracic spine, low grade B. Supratentorial, anaplastic C. Fourth ventricular, tanycytic D. Filum terminale, myxopapillary |
Correct answer is D. RATIONALE: The myxopapillary subtype of ependymoma is generally more indolent as often occurs in the lumbosacral region. Tumors of the filum terminale usually can be more completely resected and have a better prognosis than tumors of other sites. |
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297. Low-grade oligodendrogliomas most commonly are located in the: A. cerebellum. B. parietal lobe. C. frontal lobe. D. hippocampus. |
Correct answer is C. RATIONALE: Low-grade oligodendrogliomas most commonly occur in the frontal lobe. |
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314. Which of the following types of tumor is most likely associated with the EGFR V3 mutant? A. Glioblastoma B. Meningioma C. Squamous cell carcinoma D. Nasopharyngeal carcinoma |
Correct answer is A. RATIONALE: The V3 mutant of EGFR is associated with glioblastoma (GBM). The presence of this mutation suggests that not all EGFR-based therapies will be active in GBM. EGFR V3 specific immunotherapies are in phase III clinical trials. |
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345. What is the 5-year local recurrence rate for a completely resected grade I meningioma? A. 01% B. 10% C. 20% D. 30% |
Correct answer is B. RATIONALE: The recurrence rate for a completely resected grade I meningioma at 5 years is 10% (1% to 2% per year). |
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13. What is the half-life of the most common radio-isotope instilled to treat cystic craniopharyngiomas? (A) 7 days (B) 14 days (C) 60 days (D) 90 days |
Key: B Rationale: 32P is most commonly instilled into cystic cavities from craniopharyngioma. The half-life of this beta emitter is approximately 14 days. |
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