Primary leiomyosarcoma arising from the greater omentum in a 15-year-old girl.

We present here a case of primary leiomyosarcoma of the greater omentum in a 15-year-old girl. A laparotomy revealed a huge abdominal mass arising from the greater omentum. The tumor accompanied intra-abdominal dissemination, but had not invaded the muscle layer of the gastrointestinal tracts. An almost complete omentectomy and reduction of many disseminated tumors of abdominal wall and mesentery were performed for the case. The tumor was diagnosed as a leiomyoscarcoma by histological and immunohistochemical examinations. After the surgery, combination chemotherapy with cisplatin, ifosfamide, and pirarubicin was carried out. Leiomyosarcoma of the greater omentum in a young girl is extremely rare.