A case of extrahepatic bile duct cancer with distant metastases showing pathological complete response to treatment combining gemcitabine and cisplatin.

The patient was a 69-year-old female with a chief complaint of yellow staining of her urine. A detailed physical examination and laboratory tests were carried out, and as a result, her condition was diagnosed as unresectable advanced extrahepatic cholangiocarcinoma with liver metastases. Chemotherapy using gemcitabine + cisplatin was initiated, and computed tomography after six cycles revealed that the liver metastases had disappeared, and that a partial response was achieved in the primary tumor. After tan cycles, a pylorus-preserving pancreaticoduodenectomy was performed as conversion surgery, and as a result, a pathological complete response was achieved in the primary tumor. After the primary lesion was resected, we were able to start an adjuvant chemotherapy immediately. Approximately 19 months have passed since the surgery, and the patient is currently alive and recurrence-free. If an improvement of the outcomes of chemotherapy in unresectable advanced biliary tract carcinomas is achieved in the future, there could be an increase in the number of treatment-responsive cases like the one reported in this study. Accumulating a large number of cases successfully treated by conversion surgery, and conducting a detailed analysis of the postoperative course, may help design adequate treatment strategies.