[A Resected Case of Leiomyosarcoma Originating from the Ovarian Vein].

We present a 46-year-old female patient who underwent resection of a retroperitoneal tumor, which was found by medical check-up. The tumor which was elastic hard and had good mobility displaced the duodenum to her abdominal wall. Since her right ovarian vein adhered to the tumor, we removed the tumor with the ligated vein. Pathological findings showed the tumor consisted of spindle-shaped cells with pleomorphic nucleus and it presented the fascicular growth pattern. Additional immunostaining showed positive for HHF35, h-caldesmon. Because the leiomyosarcoma connected with the smooth muscle of the right ovarian vein, we considered the vascular smooth muscle was the origin of the tumor. It is 2 years after the operation, there has been no local recurrence or metastasis.