Small cell osteosarcoma of the parietal region: a unique case at an unusual site.

Small cell osteosarcoma is a rare tumour that histologically mimics Ewing sarcoma, mesenchymal chondrosarcoma and lymphoma, the presence of osteoid being diagnostic. This variant needs different management protocol, being non-radiosensitive and behaving more aggressively than conventional osteosarcoma. The aim of this article is to highlight such an entity at an unusual site--the parietal region--with unique diagnostic, treatment and prognostic considerations in a 16-year-old girl.