Extraosseous osteosarcoma - two cases.

Two patients with extraosseous osteosarcoma of the gluteal region are presented. In one early case liquifaction of the tumour delayed the diagnosis due to confusion with a cold abscess. In the second patient the tumour developed in a region that had been subjected to post-operative radiotherapy for a uterine carcinoma seven years earlier. In both patients the tumour developed rapidly and with a fatal outcome only a few months after apparently satisfactory local excision.