{"entity":{"id":"gapps","kind":"term","name":"Gastric adenocarcinoma and proximal polyposis of the stomach (GAPPS)","aka":["GAPPS","APC promoter 1B gastric polyposis"],"tldr":"Gastric adenocarcinoma and proximal polyposis of the stomach is a rare inherited condition, caused by a change in the control region of the APC gene, that fills the upper stomach with polyps and raises the risk of stomach cancer rather than bowel cancer. Stomach checks start at 15, and removing the stomach is considered by 30 to 35.","summary":"Caused by pathogenic variants in the APC promoter 1B, with fundic gland polyposis of the proximal stomach and a propensity to gastric rather than colorectal cancer. The AACR 2024 paediatric update, which added it after the 2017 recommendations, advises upper endoscopy from 15, consideration of prophylactic gastrectomy by 30 to 35 according to fundic gland polyps, dysplasia and family history, and a single baseline colonoscopy at 15 or at diagnosis if later, as it does not carry a high colorectal cancer risk.","asOf":"2026-11-04","links":[{"label":"MacFarland, Clin Cancer Res 2024: paediatric screening in hereditary gastrointestinal cancer syndromes (AACR update)","url":"https://doi.org/10.1158/1078-0432.ccr-24-0953"},{"label":"Orphanet ORPHA:314022","url":"https://www.orpha.net/en/disease/detail/314022"}],"tags":["gap-fill","hereditary"],"related":[],"cancers":["gastric"],"sections":[],"technologies":["germline-testing"],"targets":["apc"],"drugs":[],"companies":[],"institutions":[],"pathways":[],"terms":["gastrectomy","endoscopy","hereditary-cancer-syndromes"],"trials":[],"people":[],"bottlenecks":[],"keyPapers":[],"journals":[],"dependsOn":[],"notes":["Orphanet ORPHA:314022. The FDA-authorised Invitae Common Hereditary Cancers Panel analyses the APC 1B promoter."],"category":"Genomics & genetics"},"route":"/terms/gapps/","neighbours":{"cancer":[{"id":"gastric","kind":"cancer","name":"Gastric & gastro-oesophageal junction cancer","route":"/cancers/gastric/"}],"technology":[{"id":"germline-testing","kind":"technology","name":"Germline (hereditary) testing","route":"/technologies/germline-testing/"}],"target":[{"id":"apc","kind":"target","name":"APC","route":"/targets/apc/"}],"term":[{"id":"endoscopy","kind":"term","name":"Endoscopy (EGD, EUS, ERCP)","route":"/terms/endoscopy/"},{"id":"gastrectomy","kind":"term","name":"Gastrectomy","route":"/terms/gastrectomy/"},{"id":"hereditary-cancer-syndromes","kind":"term","name":"Hereditary cancer syndromes","route":"/terms/hereditary-cancer-syndromes/"}],"drug":[{"id":"invitae-common-hereditary-cancers-panel","kind":"drug","name":"Invitae Common Hereditary Cancers Panel","route":"/drugs/invitae-common-hereditary-cancers-panel/"}]}}