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57 Cards in this Set
- Front
- Back
What type of tumor is rhabdomyosarcoma (RMS)?
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- malignant tumor of mesencymal cell origin
- arises from cells of skeletal muscle lineage |
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Can this tumor develop in tissues in which striated muscle cells are not normally found?
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Yes
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T or F: RMS is a small, round blue-cell tumor
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True
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When is RMS classification given to a tumor
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when muscle cell characteristics are noted on path review
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What are muscle cell characteristics that are seen in RMS?
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cross striations on muscle proteins, such as actin, myosin, desmin, myoglobin, Z-band protein, & myoD
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What different classifications does RMS have?
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1. botryoid/spindle cell
2. embryonal 3. alveolar 4. undifferentiated |
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What classification of RMS has best prognosis? worst?
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Best = botryoid/spindle cell
Worst = Alveolar & undifferentiated (intermediate = embryonal) |
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What features are typically clustered at diagnosis?
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1. Age at diagnosis
2. Primary site of tumor 3. Histology |
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What does RMS typically look like for patients less than 8 years of age?
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Head & neck tumors
Embryonal if they arise from the orbit |
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What does RMS typically look like for adolescent patients?
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Extremity tumors
Alveolar variety |
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What patient population is RMS almost exclusively seen in?
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Infants
tumor develops from vagina or bladder |
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What patient's typically have botryoid RMS tumors?
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older chilren
arises from nasopharynx |
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Rhabdomyosarcoma is the 3rd most common extracranial solid tumor of childhood after what 2 cancers?
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1. Neuroblastoma
2. Wilms's tumor |
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At what age are most RMS diagnosed?
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Before age 9yrs
early-to-mid adolescents |
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T or F: RMS occurs sporadically in the majority of cases
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True
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What familial syndromes has RMS been associated with?
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1. Neurofibromatosis
2. Li-Fraumini - both are linked to p53 tumor suppressor gene 3. Beckwith-Wiedemann syndrome [abnrmly on 11p15- where insulin-like growth factor (IGF-2) |
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What is suggested when considering treatment for children with the familial syndromes associated w/RMS?
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Kid w/these germline mutations need dose adjustments to radiation, epipodophyllotoxins, & Alkylating agents
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What genetic alterations are associated with the alveolar subtype of RMS?
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Translocation of chromosome 2 and 13 [t(2;13)] & PAX3 gene involvement
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What is the PAX3 gene believed to regulate?
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Neuromuscular development - therefore it interferes with normal growth - contributing to RMS
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Is the presence of the PAX3 gene favorable or adverse prognostic factor?
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Adverse prognostic factor
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What genetic alteration is the embryonal subtype assoc. with?
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LOH at 11p15
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What 2 subtypes of RMS are associated with overproduction of IGF-2?
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Alveolar & embryonal
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In what 2 ways is RMS most commonly detected?
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1. Appearance of a mass
2. Disturbance of normal body function |
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What sites are 35% of RMS tumors located?
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Head & neck (includes orbits & parameningeal areas)
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What are signs & symptoms associated with orbital tumors?
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Orbital = proptosis & opthalmoplegia
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What are signs & symptoms associated with Non-orbital parameningeal tumors?
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Non-orbital parameningeal = nasal, aural, sinus obstruction, muco-purulent or sanguinous discharge, cranial-nerve palsies, or signs increased ICP
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What percentage of RMS tumors are most often found in genitourinary tract?
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25% (most bladder or prostate)
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What are some signs & symptoms of genitourinary RMS tumors?
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Hematuria, urinary obstruction, extrusion of tumor, vaginal discharge, painless pelvic or testicular mass, constipation
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20% of RMS tumors that exhibit swelling of soft tissues, w/ or w/out tenderness or erythema are found where?
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Extremities
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What benefit does a bone scan & CT of chest provide when assessing extent of disease?
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rule out osseous metastasis
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What is the greatest prognostic factor in an RMS diagnosis?
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presence of metastatic disease
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Is the 4-year survival rate better or worse for PAX3 vs PAX7?
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PAX7 = >70% 4-year survival rate
PAX3 = 10% 4-year survival rate |
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What patients have a significant increased risk of relapse and death with metastatic disease?
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Those w/tumors that express PAX3
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What prognosis would a patient have if they are diagnosed with alveolar histology & 2 metastatic sites?
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Poor prognosis
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What RMS group was formed in 1972 and enrolls most patients today?
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IRS (Intergroup Rhabdomyosarcoma Study)
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What are the 3 IRS recognized modalities of treatment for RMS?
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1. Surgical removal (if feasible)
2. Radiation 3. Chemotherapy |
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Is surgery usually feasible for head & neck tumors?
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Yes; lymph node involvement low - node sampling not necessary
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What surgical resection is performed when a paratesticular tumor is identified?
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Radical inguinal orchiectomy & resection of spermatic cord; lymph node sampling controversial
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Why are vulvar or vaginal tumors not typically excised?
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Most respond very well to chemotherapy
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What surgical procedure may be warranted with uterine and proximal vaginal tumors?
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Hysterectomy (avoiding oophorectomy)
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Why have previously radical surgeries of bladder and prostate tumors been reserved now only when pts don't achieve local control with chemo & XRT?
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High morbidity when radical surgeries are performed
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What type of RMS tumors is an initial complete resection of tumor recommended?
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Extremity tumors IF limb function will not be greatly impaired
[amputation is rarely required] - sampling of regional nodes is recommended |
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Read page 50
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Tabe 2-14 - Intergroup Rhabdomyosarcoma Studies Grouping and Staging Criteria
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When is radiation therapy NOT recommended in a pt. w/RMS?
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children with Group I tumors who have had complete resection
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What is the post-Op dose of External Beam Radiation treatment (EBRT) for microscopic residual disease? for gross disease?
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Microscopic residual = 36-41Gy
Gross = 50.4 - 1.8Gy |
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When is radiation therapy usually started?
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After 9-12 weeks of chemotherapy
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What is being researched in place of radiation therapy for very young children d/t the long term side effects for this population?
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Intensity modulated radiation therapy (IMRT)
proton beams |
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What small subset of patients are NOT given chemotherapy as part of their treatment?
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Group I tumors
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What are the common chemotherapies used in the treatment of RMS?
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1. Vincristine (Oncovin)
2. Dactinomycin (Actinomycin-D) 3. Doxorubicin (Adriamycin) 4. Cyclophosphamide (Cytoxan) 5. Ifosfamide (Ifex) 6. Etoposide (VP-16) |
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What IRS-III study found that what RMS tumors have the best prognosis?
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Orbital
Nonbladder Nonprostate Genitourinary |
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What location of tumors have proven to be the worst prognosis?
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1. Extremity
2. Cranial Parameningeal 3. Truncal 4. Pelvic 5. Retroperitoneal 6. Paravertebral |
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What 2 chemo drug combination has been proven to improve outcomes for patients w/metastatic RMS in the 4th IRS study?
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Ifosfamide plus Doxorubicin
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In study IV and increase in what type of drug seemed to benefit some patients but overall did not improve the outcome for the majority of patients when compared with study III- IRS?
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Increasing the alkylator intensity
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What are the 2 major objectives of the current protocol, IRS-V?
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1. Eval the activity of irinotecan in pts w/newly diagnosed metastatic RMS
2. Eval efficacy of adding topotecan to standard 3-drug regimen for intermediate-risk tumors |
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Although rare to have recurrence 3-4yrs after treatment, what evaluations are required to confirm recurrence?
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1. biopsy or fine needle aspiration
2. with imaging studies |
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What is the treatment for local recurrence?
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1. Surgical excision
2. Chemo w/agents not previously used |
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T or F: It is almost impossible to cure metastatic recurrence
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True
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