抄録
The mesenchymal chondrosarcoma is a very rare neoplasm. A case of extraskeletal mesenchymal chondrosarcoma occurring in the left temporal fossa was reported. The patient was a 15-years-old Japanese female with a painless swelling of the left temporal region. Total removal of the tumor was then undertaken. From the findings of surgical operation, the tumor existed in the temporal muscle well separated from other surrounding tissue. The tumor was histologically diagnosed as mesenchymal chondrosarcoma originated from the temporal muscle, which was the first case in Japan. Chemotherapy with Adriamycin and Vincristin were given after the operation. About 17 months after the first operation, local recurrence was seen in the left preauricural region. Then, total removal of the tumor and postoperative chemotherapy with Aclacinon was performed. No recurrence was seen for 21 months after the last operation. The mesenchymal chondrosarcoma is characterized histologically by composition of sheets of highly undifferentiated mesenchymal cells and islands of relatively well-diffrentiated cartilage. This histological feture is sometimes difficult to distinguish from hemangiopericytoma and reticulm cell sarcoma. Radical surgery appears to be the best treatment of choice.
