Clinicopathological analysis of concomitant hepatic embryonal rhabdomyosarcoma and hepatocellular carcinoma.

Hepatic embryonal rhabdomyosarcoma (ERMS) is extremely rare. Here we report the simultaneous occurrence of hepatocellular carcinoma (HCC) and ERMS of the liver in a 40-year-old man without any symptoms. Macroscopically, the mass was composed of two different tumors. The large tumor was 4.5×4×4cm and was poorly circumscribed and soft in the central region of left lateral lobe of the liver with apparently focal necrosis. The small tumor, with diameter of 1cm, was adjacent to the large tumor without clear boundary. Histologically, the large tumor was composed of numerous spindle-shaped or round cells with brightly eosinophilic cytoplasm as well as pathologic mitosis. Immunohistochemical staining was positive for MyoD1 and myogenin in nuclear testing. However, in the small tumor, cells demonstrated hepatocyte differentiation and were focally positive for HepPar1. A diagnosis of concomitant ERMS and HCC of the liver was made. The patient received no adjuvant treatment after hepatic left lateral lobectomy. The regular follow-up observation conducted by imaging examinations displayed that there was no sign of recurrence or metastasis of the mass over 32 months. To our knowledge, this is the first case report of ERMS of the liver associated with HCC. The diagnosis can only be made by pathological examination. The primary therapy method for this tumor is operative resection.