A Case of Advanced Gastric Cancer in which Pancreaticoduodenectomy was Successfully Avoided by the Use of Nivolumab Combination Chemotherapy

Abstract

A 75-year-old man was referred to our department after upper gastrointestinal endoscopy to investigate epigastric pain identified type 3 gastric cancer in the lesser curvature of the gastric angle. Computed tomography (CT) did not show any distant metastases, and the diagnosis was cT4aN1M0, cStage III. Resection was attempted, but the tumor was directly invading the head of the pancreas, and since R0 resection could not be performed without pancreaticoduodenectomy (PD), the attempt was abandoned (cT4b (pancreas) N1M0, cStage IVA). It was then decided to administer preoperative chemotherapy, and combination chemotherapy with capecitabine, oxaliplatin, and nivolumab was started. CT after eight courses showed that the primary lesion had contracted dramatically, and there was now a clear margin between the tumor and the head of the pancreas. It was determined that standard R0 resection was now feasible, and laparoscopic distal gastrectomy was performed. The final pathological diagnosis was por2, ypT4a, Ly1a, V1a, pPM0, pDM0, ypN3a, ypStage IIIB, and the histological response to preoperative chemotherapy was assessed as Grade 1a. Whether to perform PD, a highly surgically invasive procedure, for patients with pancreatic invasion of gastric cancer is often the subject of debate, but this case suggests that, with the use of preoperative chemotherapy including nivolumab, one may be able to avoid PD and aim for R0 resection by means of standard surgery.