Purpose

Gastric cancer afflicts 27,000 Americans annually and carries a dismal prognosis. One reason for poor outcomes is late diagnosis, as the majority of gastric cancers in the United States are diagnosed at a relatively advanced stage where curative resection is unlikely. Gastric intestinal metaplasia (GIM) is a precancerous change of the stomach which increases risk for subsequent gastric cancer multiple-fold. The Gastric Precancerous Conditions Study (GAPS) is an observational study with two over-arching objectives: 1) improve the non-invasive identification of patients with GIM, and 2) develop biological markers to predict the subset of GIM which will progress onto gastric cancer. To achieve Aim 1, a case-control study (N=300 pairs) matching cases of GIM with age-/gender-matched controls will be recruited form the population of subjects undergoing clinically-indicated endoscopy. Determination of gastric pathology will be made by two, independent gastrointestinal pathologists. At time of endoscopy, a detailed clinical questionnaire is administered by face-to-face interview. Saliva and blood is collected prior to endoscopy. At time of endoscopy, protocoled clinical biopsies (per Revised Sydney Protocol) as well as additional research specimens are collected. Scoring of GIM will be performed based on the Operative Link for GIM scoring system. To achieve Aim 2, patients with histologically-confirmed GIM (N=300) will be followed longitudinally. Biennial endoscopic surveillance will be performed, with repeat biopsies, specimen collection, and histologic scoring. Progression of GIM will be defined as upstaging of GIM score, or development of either dysplasia or carcinoma on any biopsy.