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What is Which of the following is the commonest malignancy causing bilateral proptosis in the pediatric population? and explain in detail?
The common causes of bilateral proptosis include granulocytic sarcoma due to AML / Myelodysplastic syndrome and metastatic neuroblastoma. Rhabdomyosarcoma and retinoblastoma rarely produce bilateral proptosis. Causes of bilateral proptosis include: 1. Developmental anomalies of the skull: craniofacial dysostosis e.g., oxycephaly (tower skull). 2. Osteopathies: Osteitis deformans, rickets, and acromegaly. 3. Inflammatory conditions: Mikulicz's syndrome and late stage of cavernous sinus thrombosis. 4. Endocrinal exophthalmos: It may be thyrotoxic or thyrotropic. 5. Tumors: These include symmetrical lymphoma or lymphosarcoma, secondaries from neuroblastoma, nephroblastoma, Ewing's sarcoma and leukemic infiltration. 6. Systemic diseases: Histiocytosis, systemic amyloidosis, xanthomatosis and Wegener's granulomatosis. The most common malignancy causing unilateral proptosis in children: In India - Retinoblastoma In Western population - Rhabdomyosarcoma The most common primary orbital malignancy in children - Rhabdomyosarcoma The most common metastatic orbital malignancy in children - Neuroblastoma Reference : Khurana; 4th edition; Page no: 381