Inflammatory myofibroblastic tumor of the liver.

We report a case of hepatic inflammatory myofibroblastic tumor in a 26-year-old African American man who presented with right upper quadrant pain, weight loss, and fatigue during the previous year. Hepatomegaly was found on physical examination. Laboratory findings were significant for mild normocytic, normochromic anemia and elevated erythrocyte sedimentation rate. Imaging studies showed 2 contiguous masses suspicious for malignancy. A left partial hepatectomy was performed; the preoperative differential diagnosis was for angiosarcoma and hepatocellular carcinoma. The resected liver specimen showed 2 contiguous, firm, tan-white nodules that microscopically represented a proliferation of spindled myofibroblast cells set in an inflammatory and collagenized background. The spindle cells were strongly reactive for smooth muscle actin but negative for ALK-1. The morphologic and immunophenotypic findings, coupled with the clinical presentation, were consistent with an inflammatory myofibroblastic tumor of the liver.