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29 Cards in this Set
- Front
- Back
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List 4 Primary Malignant Neoplasms that occur in children.
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Rhabdomyosarcoma
Osteosarcoma Chrondrosarcoma Fibrosarcoma |
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Are tumours of EPITHELIAL origin in the orbit extremely rare?
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YES! The large majority are SARCOMAS!
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Which is the most common primary pediatric orbital malignancy?
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Rhabdomyosarcoma
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What is a rhabdomyosarcoma?
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an EMBRYONAL SARCOMA.
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What is the source of a rhabdomyosarcoma?
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Undifferentiated MESENCHYMAL CELL nests. They have the potential to differentiate into striated muscle.
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What is the ave age of onset?
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5 - 7 years
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What % manifest before before the age of 1 year
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5%
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What % occurs before the age of 16 years?
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90%
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Where in the orbit is the tumour most commonly situated?
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Superonasal or retrobulbar
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Where else would you expect to find it in the orbit?
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Superiorly & Inferiorly
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What is the usual presenting sign of a pediatric rhabdomyosarcoma?
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Acute onset unilateral proptosis
Results in downward and lateral displacement of the globe |
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What other symptoms may the patient present with?
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Eyelid swelling, ecchymosis, injection
Palpable mass Ptosis and strabismus Regional lymphadenopathy (mets) |
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What symptoms are uncommon?
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Pain and vision loss
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How many histological types are there?
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4
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What are they?
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Embryonal
Alveolar Botryoid embryonal Pleomorphic (Rabi - pregnant w embryo - bursts out bird - then turns into a robot and smashes to the ground - into a ballet class doing plies) |
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Which is the most common type?
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Embryonal
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Describe features of embryonal
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Most common type
Histo: loose fascicles of undifferentiated spindle cells . Few cells contain striations Site: superonasal quadrant |
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Which is the second most common type?
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Alveolar
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Describe its features
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Second most common
Most malignant form. Poor prognosis Histo: poorly differentiated tumor cells (rhabdomyoblasts) compartmentalized (alveolar like) by orderly connective tissue septae Site: inferior (down in the grave) |
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Which type is rarely found in the orbit?
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Botryoid embryonal (grapelike)
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Features of botryoid embryonal
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Rarely found in the orbit
variant of embryonal that occurs in grape-like clusters May originate from the conjunctiva or paranasal sinuses |
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Which is the rarest form?
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Pleomorphic
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Features?
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Rarest form
Occurs in adults Well differentiated |
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What is the disease course?
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Rapid progression
Bony invasion Metastasis to LN, marrow, brain & lung |
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What are the features on CT?
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Irregular, but well circumscribed mass of uniform density. Often with adjacent bony destruction
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What must be done immediately when this malignancy is suspected?
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Biopsy
Metastatic work up: CXR, LP, Marrow biopsy |
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What is the treatment?
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Small encapsulated or well-localised: excised in entirety
Large, extensive: Chemo (vin, actinomy, cyclophos) & ray Excenteration rarely indicated |
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What is the prognosis?
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Based on the staging and histo
Best to worst: adult pleomorphic > embryonal (incl botryoid) > alveolar Primary ORBITAL rhabdo has the best prognosis of any site Long-term survival: nearly 90% |
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What is the DDx?
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Orbital cellulitis
Idiopathic orbital inflammation Neuroblastoma Lymphangioma with heamorrhage Capillary heamangioma Ruptured dermoid cyst |
