Clinicopathological characteristics and pathogenic germline variants of gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS)

Abstract

Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS) is an autosomal dominant inherited disease clinically characterized by gastric cancer and fundic gland polyposis (FGPsis). Germline variants of the APC promotor 1B have been reported as pathogenic variants in GAPPS families. Most GAPPS families have been reported in Western countries; however, only a few GAPPS families have been reported from Japan. Appropriate surveillance including gastrointestinal endoscopy and indication of surgical gastrectomy for GAPPS patients have not been established because of the lack of knowledge of GAPPS and the high positivity rate for Helicobacter pylori infection in Japan. A large-scale investigation of clinicopathological characteristics and pathology is required to establish of a surveillance and treatment strategy for GAPPS.