Martin E O'Malley1, Tanya P Chawla2, Lisa P Lavelle3,4, Sean Cleary5, Sandra Fischer6. 1. Joint Department of Medical Imaging, Princess Margaret Hospital, University of Toronto, 3-961, 610 University Avenue, Toronto, ON, M5G 2M9, Canada. martin.o'malley@uhn.ca. 2. Joint Department of Medical Imaging, Mount Sinai Hospital, University of Toronto, 600 University Avenue, Room 567, Toronto, ON, M5G 1X5, Canada. 3. Joint Department of Medical Imaging, Toronto General Hospital, University of Toronto, NCSB 1C572, 585 University Avenue, Toronto, ON, M5G 2N2, Canada. 4. Department of Radiology, NYU Langone Medical Center, 660 First Avenue, 3rd Floor, New York, NY, 10016, USA. 5. Division of Hepatobiliary-Pancreatic Surgery, Toronto General Hospital, University Health Network, 585 University Avenue, Toronto, ON, M5G 2N2, Canada. 6. Laboratory Medicine Program, Toronto General Hospital, University Health Network, University of Toronto, 200 Elizabeth Street, Toronto, ON, M5G 2C4, Canada.
Abstract
OBJECTIVES: The purpose of our study was to describe the CT and MRI features of primary PEComas of the liver and to document the associated clinical outcomes. METHODS: Retrospective study included 20 patients with primary hepatic perivascular epithelioid cell tumors (PEComa) with pathology and clinical outcomes for correlation. RESULTS: Study group included 20 patients: 16 women, 4 men; mean age 53 (range 35-77) years. Initial pathology diagnoses were classic angiomyolipoma (AML) (n = 11), epithelioid AML (n = 7), and PEComa not otherwise specified (n = 2). Mean tumor size was 5.1 (range 1.3-15.0) cm. CT/MRI features included well-defined margins 20/20 (100%), arterial enhancement 18/19 (95%), subcapsular location 17/20 (85%), heterogeneous 16/20 (80%), dysmorphic vessels 14/20 (70%), fat 13/20 (65%), hemorrhage 4/20 (20%), cystic components 4/20 (20%), and calcification 1/20 (5%). At the time of discovery, 18 patients were asymptomatic and their tumors were incidentally detected on imaging, and 2 patients were symptomatic. Ultimately, 18 tumors were benign and 2 developed metastases. CONCLUSIONS: On CT/MRI, most primary hepatic PEComas were well-defined, arterial enhancing, subcapsular, heterogeneous masses that often had dysmorphic vessels and contained fat. Most tumors were benign but complications included local symptoms, bleeding, and malignant change.
OBJECTIVES: The purpose of our study was to describe the CT and MRI features of primary PEComas of the liver and to document the associated clinical outcomes. METHODS: Retrospective study included 20 patients with primary hepatic perivascular epithelioid cell tumors (PEComa) with pathology and clinical outcomes for correlation. RESULTS: Study group included 20 patients: 16 women, 4 men; mean age 53 (range 35-77) years. Initial pathology diagnoses were classic angiomyolipoma (AML) (n = 11), epithelioid AML (n = 7), and PEComa not otherwise specified (n = 2). Mean tumor size was 5.1 (range 1.3-15.0) cm. CT/MRI features included well-defined margins 20/20 (100%), arterial enhancement 18/19 (95%), subcapsular location 17/20 (85%), heterogeneous 16/20 (80%), dysmorphic vessels 14/20 (70%), fat 13/20 (65%), hemorrhage 4/20 (20%), cystic components 4/20 (20%), and calcification 1/20 (5%). At the time of discovery, 18 patients were asymptomatic and their tumors were incidentally detected on imaging, and 2 patients were symptomatic. Ultimately, 18 tumors were benign and 2 developed metastases. CONCLUSIONS: On CT/MRI, most primary hepatic PEComas were well-defined, arterial enhancing, subcapsular, heterogeneous masses that often had dysmorphic vessels and contained fat. Most tumors were benign but complications included local symptoms, bleeding, and malignant change.