Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) is a rare hereditary syndrome characterized by fundic gland polyposis and an increased risk of gastric adenocarcinoma. We report a case of gastric cancer associated with clinically suspected GAPPS that was successfully treated with robot-assisted total gastrectomy. A 26-year-old woman presented with epigastric pain, and upper gastrointestinal endoscopy revealed diffuse fundic gland polyposis extending from the gastric fundus to the lower gastric body. Biopsy specimens demonstrated well-differentiated tubular adenocarcinoma. No polyps were identified in the gastric antrum, duodenum, or colon. Based on the characteristic endoscopic findings, family history, and exclusion of other hereditary polyposis syndromes, the patient was clinically suspected to have GAPPS. Contrast-enhanced computed tomography suggested possible splenic hilar lymph node metastasis, and robot-assisted total gastrectomy with D2 lymphadenectomy and spleen-preserving splenic hilar lymph node dissection was performed. The postoperative course was uneventful, and the patient was discharged on postoperative day seven. Histopathological examination demonstrated multiple intramucosal well-differentiated tubular adenocarcinoma lesions without lymph node metastasis. The patient remains free of recurrence two years and six months after surgery. GAPPS carries a substantial risk of malignant transformation at a relatively young age, and accurate endoscopic evaluation may be challenging. In young patients requiring total gastrectomy, robot-assisted surgery may represent a feasible minimally invasive option that facilitates precise dissection in technically demanding procedures.
Ihashi et al. (2026) studied this question.