Which of the following is not a small round cell tumor?
Neuroblastoma
Retinoblastoma
Ewing's sarcoma
Hemangiosarcoma
Ans. is 'd' i.e., hemangiosarcomaSmall round blue cell tumors:* Histologically many of the malignant paediatric neoplasms are unique.* They tend to have a more primitive (embryonal) rather than pleomorphic anaplastic microscopic appearance.* Often characterized by sheets of cells with small round nuclei.* Frequently exhibit features of organogenesis specific to the site of tumour origin (therefore these tumours are frequently designated by suffix - blastoma).* Owing to their primitive histological appearance many childhood tumours have been collectively referred to as small round blue cell tumourThe differential diagnosis of small round blue cell tumours includesNeuroblastomaRhabdomyosarcomaRetinoblastomaWilms tumoursEwings sarcomaMedulloblastomaLymphomaPrimitive neuroectodermal tumoursBurkitt lymphoma