[A Resected Case of Gallbladder Neuroendocrine Cancer Found as a Liver Mass]

Our patient was a 72-year-old man in whom a liver mass was identified on abdominal ultrasonography at the examination for which he was referred to our hospital. Contrast-enhanced CT showed that the liver mass was a hemangioma with a surrounding AP shunt. Gallbladder wall thickening could not be ruled out as gallbladder cancer; however, a high possibility of adenomyomatosis was considered. EOB-MRI determined that the gallbladder wall thickening was adenomyomatosis and liver mass was a metastatic malignant tumor of unknown primary origin. Our policy was to resect gallbladder adenomyomatosis and the liver tumor for diagnostic purposes. Cholecystectomy plus hepatic S4a subsegmental resection and hepatoduodenal mesenteric lymph node dissection were performed. The histopathological diagnosis was neuroendocrine cancer of the gallbladder. A similar histology of the liver mass suggested continuity from the gallbladder tumor and was considered direct infiltration. Fifteen months after the operation, no recurrence was observed.