[A case of effective preoperative chemotherapy in alveolar soft part sarcoma]

Alveolar soft part sarcoma is primarily treated by surgery, and reports of effective chemotherapy have been infrequent. We experienced a patient with alveolar soft part sarcoma in the left thigh, in whom preoperative chemotherapy with cisplatinum (CDDP) and adriamycin (ADM) was effective. This patient was a 13-year-old male who had an elastic hard mass with the size of his fist in the medial thigh. Plain X-ray revealed bone destruction with periosteal reactions in the distal diaphysis of the femur. Biopsy specimen showed alveolar growth of relatively large cells with eosinophilic or clear cytoplasm. PAS staining was positive in microgranular patterns in part of the cells, but no crystalline structure were observed. A diagnosis of alveolar soft part sarcoma was made, and chemotherapy was started. After administration of 150 mg of CDDP intraarterially twice and 50 mg of ADM intravenously 5 times, effectiveness of chemotherapy was estimated by physical and radiological findings. In the resected specimen, the margins of the soft part tumor showed shell-like ossification, suggesting the subperiosteal or intraosteal origin. Histology of the removed specimen showed that the tumor was mostly replaced by fibrous tissues, indicating the effectiveness of the preoperative chemotherapy. This disease has a relatively long course, however, the present case is considered to be another exceptional case that responded to preoperative chemotherapy.