Clear-cell chondrosarcoma. An unusual case complicated by a microinfiltrative pattern of bone marrow involvement and postsurgical myositis ossificans.

A case of clear-cell chondrosarcoma occurred in the proximal femur of a 32-year-old man. The tumor was complicated by a focus of myositis ossificans resulting from a previous intralesional biopsy. Histologic findings included an unusual marrow infiltration by the tumor. The patient was treated with wide resection and has no evidence of local recurrence or distant spread of disease 18 months later.