ARRS 2022 Abstracts


E1335. Comprehensive Review of Abdominal Pelvic Leiomyosarcomas
  1. Seng Thipphavong; Princess Margaret Cancer Centre
Leiomyosarcomas are one of the most common sarcomas to occur in the abdomen or pelvis. Radiologists working in hospital centers without a dedicated sarcoma service may not be familiar with uncommon presentations of leiomyosarcomas. We present a comprehensive imaging review of the typical and atypical locations for leiomyosarcomas to occur in the abdomen and pelvis. The objectives are to review the background, pathology, and up-to-date management of abdominal pelvic leiomyosarcomas, and present the imaging spectrum of leiomyosarcomas that can occur outside the uterus in the abdomen and pelvis.

Educational Goals / Teaching Points
Leiomyosarcomas are tumors of smooth muscle, with the uterus and retroperitoneum the most common locations for tumors to arise. Many tumors arise from the veins of the retroperitoneal compartment. Leiomyosarcomas can arise from other structures in the abdomen and pelvis, such as the liver, mesenteric veins, or gastrointestinal tract.

Key Anatomic/Physiologic Issues and Imaging Findings/Techniques
The exhibit includes a review of histopathology and genetics of leiomyosarcomas and the imaging spectrum of extravascular and vascular leiomyosarcomas than can occur in the abdomen and pelvis. It also includes up-to-date management and treatment, how to report findings, and imaging pearls.

Diagnosing a leiomyosarcoma can be difficult on imaging unless the classic features are present (i.e., uterine mass or intravascular mass). Often the diagnosis will be in the differential diagnosis for any large retroperitoneal mass that does not contain fat. Uncommon locations of leiomyosarcoma that can be seen in the abdomen and pelvis are often not diagnosed on imaging prospectively and require biopsy for diagnosis.