[A Case of Conversion Surgery for Stage Ⅳ ATP-Producing Gastric Cancer with Distant Metastasis].

We report a case in which a patient with advanced gastric cancer with liver metastasis and bulky N showed marked tumor shrinkage with chemotherapy, and underwent conversion surgery. A 77-year-old male. Patient was referred to our department because of advanced gastric cancer. Upper gastrointestinal endoscopy revealed type 2 advanced cancer in the posterior wall of the gastric antrum. Abdominal CT showed thickening of the gastric wall in the same region and bulky lymph node enlargement and para-aortic lymphadenopathy behind the stomach. Staging laparoscopy showed the primary tumor and bulky lymph nodes forming a single mass, invading the pancreas, jejunum, and mesentery, and a solitary mass in the hepatic S3. Biopsy pathology revealed adenocarcinoma. We diagnosed the advanced gastric cancer cT4b(pancreas, jejunum), N2M1 (LYM, HEP), P0CY0, Stage ⅣB. After 2 courses of systemic chemotherapy FOLFOX/nivolumab, total gastrectomy, D2 node dissection, splenectomy pancreas tail resection, cholecystectomy, hepatic resection, partial transverse colon resection, partial jejunum resection, Roux-en-Y reconstruction. R0 resection was performed. The operative time was 620 minutes and blood loss was 1,025 mL. Pathologically, the patient was diagnosed with hepatoid adenocarcinoma, ypT4bN1M1(LYM, HEP), ypStage Ⅳ. The pathological efficacy evaluation was Grade 1a in the primary tumor. The patient has been recurrence-free for 9 months since the initial diagnosis.