Recurrence of a Giant Retroperitoneal Leiomyosarcoma Six Years after the Initial Surgery

: A 51-year-old man came to our department because of a large abdominal mass. CT, MRI, and sonography revealed a large tumor adjacent to the retroperitoneal area. A resection was performed, and histologically we confirmed the diagnosis as a leiomyosarcoma originating from the retroperitoneum. Six years after the initial surgery, the patient came to our outpatient department with a complaint of nausea. A relatively large tumor was seen on a CT scan that was causing obstruction of the duodenum. Another surgery was performed with the final diagnosis as a recurrence of the leiomyosarcoma. After 3 courses of adjuvant chemotherapy with eribulin, the patient presented with abdominal distension. CT revealed a very large tumor with massive invasion to the ileum and colon. This time, we considered the tumor unresectable, and administered chemotherapy with a combination of doxorubicin and ifosfamide. However, after 1 course, the patient's condition worsened and he died of the disease 3 months after the chemotherapy.