S-1/irinotecan/oxaliplatin chemotherapy achieved a pathological complete remission in advanced pancreatic carcinoma.

Chemotherapy has been developed for many years for malignancies, including advanced pancreatic cancer, downsizing the primary site, thereby enabling complete cure with the combination of conversion surgery. Pathological complete remission from operation samples was usually identified as a promising indication for a good prognosis for many carcinomas. Several case reports consisting of pathological complete remission after chemotherapy application have been reported but no case of pathological complete remission that resulted from successful extensive resection by surgery after S-1, irinotecan, and oxaliplatin (SIROX) chemotherapy. A 48-year-old male patient was hospitalized due to abdominal pain which turned out to be a 25 mm-sized advanced uncinate process of pancreatic cancer with possible duodenum invasion and hepatic metastasis. The tumor had decreased after administering 23 sessions of modified SIROX chemotherapy, and he underwent pylorus-preserving pancreaticoduodenectomy with portal vein resection. He was successfully managed with conservative treatment and discharged 12 days postoperatively despite his postoperative weakness. He had been taking S-1 pills for 6 months and until now, 3 years postoperatively, with no relapse. The final pathology reported complete tumor regression. Therefore, we emphasize the oncologic significance of chemotherapy in the uncinate process of pancreatic cancer and the potential role of conversion surgery.