[A case of initially unresectable gallbladder cancer with surgical resection after chemotherapy with gemcitabine]

A 75-year-old woman was admitted to our hospital with elevated serum hepatic enzyme levels. After evaluation with imaging studies, she was diagnosed as having gallbladder cancer, which had invaded the liver and hepatic artery, with lymph node metastases. The tumor was considered unresectable, and the patient received chemotherapy with gemcitabine (GEM)alone. Six months later, computed tomography(CT)indicated shrinkage of the gallbladder tumor and disappearance of lymph node metastases. Surgical resection was planned. However, liver metastasis was suspected on the basis of macroscopic findings, and the patient underwent gallbladder bed resection. Pathological examination indicated that almost all of the tumor cells in the gallbladder were viable; however, there were no tumor cells in the liver nodule and lymph node. The postoperative course was uneventful. The patient received adjuvant chemotherapy with GEM and was alive without recurrence 17 months after tumor resection. Immunohistochemical analysis showed that 80.9% of the tumor cells were positive for CD133, a cancer stem cell marker. This case illustrates a possible relationship between cancer stem cells and chemoresistance.