Abstract Background Rhabdomyosarcoma (RMS), a malignant neoplasm that normally differentiates to form striated muscle, is the most common type of childhood soft tissue sarcoma. However, it infrequently occurs in adults and is uncommon in the liver. We herein report a case of RMS of the liver in an adult. Case presentation A 73-year-old woman was admitted to our institution for investigation of a hepatic mass. She had been followed for primary biliary cirrhosis for the past 20 years. A contrast-enhanced computed tomography scan of the abdomen showed a 12- × 10-cm heterogeneous low-density mass lesion containing cystic and solid components. A percutaneous liver biopsy was performed, and poorly differentiated cancer containing an RMS cell-like component was observed. The patient was diagnosed with RMS of the liver, and open surgery with right hepatic lobectomy was performed. Histopathological examination confirmed a diagnosis of pleomorphic RMS of the liver. The patient died of rapid progression of the tumor 6 months after the operation. Conclusions The tumor site in the present case is rare. The details of this case add to the current evidence base regarding establishment of the standard diagnosis and treatment of this rare condition. We recommend consideration of RMS as a differential diagnosis for hepatic tumors.
