Undifferentiated carcinoma of the mandible detected simultaneously with the liver: A case report

We herein report a rare case of undifferentiated carcinoma that originated in the mandible with the same pathological findings as seen in the liver. A 64-year-old man underwent surgery for a hepatic tumor in October 2006, and the pathological diagnosis was undifferentiated carcinoma. The patient was referred to our department in January 2007, when whole-body positron emission tomography/computed tomography showed the uptake of fluorodeoxyglucose in the right mandibular ramus. The patient underwent right hemimandibulectomy in April 2007. The resected tumor was also undifferentiated carcinoma. In May 2014, seven years after the lower mandibular operation, the tumor recurred at the site corresponding to the right mandibular ramus after resection, and tumor resection and right neck dissection were performed. As a result of the histopathological examination, the undifferentiated carcinoma findings were the same as before. There have been no signs of local recurrence or metastases for over six years since the second mandibular surgery.