Retroperitoneal Leiomyosarcoma

Abstract

Leiomyosarcoma is a soft tissue sarcoma arising from the uterus, gastrointestinal tract, and soft tissue smooth muscle cells, accounting for 5–10% of all soft tissue sarcomas. It is the third most common soft tissue sarcomas following liposarcoma and malignant fibrous histiocytoma. Nowadays, leiomyosarcoma is generally classified into three categories: (a) leiomyosarcoma in the retroperitoneum or peritoneal cavity, which is the most common type, of which 1/2 to 2/3 occurs in the retroperitoneum; (b) skin and subcutaneous leiomyosarcoma, with the best prognosis among all the three; and (c) prototype vascular smooth muscle sarcoma, which is the rarest type. Primary retroperitoneal leiomyosarcoma, accounting for 11% of all malignant retroperitoneal tumors, can occur at any age, is mostly seen in people aged 40–70 years, and is more prevalent in women than in men (ratio of 2:1). Most of the tumors grow invasively and are difficult to treat, with dismal prognosis and the lowest survival rate among all soft tissue sarcomas.