Ewing's sarcoma arises from

Ans. d (Primitive neuroectodermal cells). (Ref. Robbin, Pathologic Basis of Diseases 5th/833)PNETs# Ewing's Sarcoma is the highly malignant primary bone neoplasm having specific cytogenetic analysis i.e. t (11,12), characterized by small round cells (pseudo-rossets) and is thought to be a primitive neuroectodermal tumor (PNET) with 75% patients being < 20 years age and having male predilection.# Other PNETs include- Medulloblastoma,- Pineoblastoma,- Neuroblastoma,- Askin tumor,- Retinoblastoma, etc.