Spontaneous Tumor Rupture as the Initial Manifestation of Primary Hepatic Leiomyosarcoma (LMS)

Abstract

Purpose: A 42-year-old male with no significant past medical history presented to the emergency room with severe sudden onset right upper quadrant abdominal pain and nausea, developed over hours. Physical examination revealed tender hepatomegaly without any signs of peritonitis. Contrast-enhanced computed tomographic scan of abdomen showed a 13.7 x 11.4 x 11.8 cm, well-circumscribed, heterogeneous dense mass in the right lobe of the liver, with the evidence of sub-capsular and free intra-peritoneal hemorrhage. Gadolinium-enhanced magnetic resonance imaging showed a centrally increased T1 signal consistent with internal hemorrhage, and a T2 hypo-intense rim compatible with a capsule or pseudocapsule. No lymph node involvement or vascular obstruction was noted. Diagnostic laboratory data was fairly benign, including alpha-fetoprotein levels. He underwent segment V hepatectomy with adhesiolysis and evacuation of hematoma. Grossly, the specimen revealed a firm, grey-white mass measuring 20 x 11 x 10 cm with areas of necrosis and hemorrhage. Microscopy revealed areas of fascicular growth in a highly pleomorphic neoplasm with high mitotic count and abundant necrosis with storiform and myxoid areas, suggestive of LMS. The tumor cells were positive for desmin stain, but negative for smooth muscle actin, S-100, DOG-1, CD 117, and epithelial membrane antigen. He had an uneventful post-op recovery, and seven months after the surgery, he is doing well, with no recurrence. Primary hepatic LMS is usually asymptomatic, and can attain a fairly large size before symptom development. It is found more often in patients with Epstein-barr virus infections, lymphoma, or post-renal transplant patients. Unlike other hepatocellular cancers (HCC), imaging and serological markers aren't helpful in diagnosis, and the cornerstone for diagnosis is usually histopathology. Surgical resection of tumor with R0 tumor-free margin resection offers the best outcome. The roles of chemotherapy, radiotherapy, and liver transplant in these tumors are not clearly defined yet. Primary hepatic LMS is a rare tumor comprising < 2% of all HCC, which should be included in the differential diagnosis of a hepatic mass in the absence of imaging features or serological markers suggestive of HCC. Surgical resection is the best available treatment for now.