Prevalence of gastric cancer versus colorectal cancer in Asians with a positive fecal occult blood test

Prior studies have reported conflicting results on the yield of esophagogastroduodenoscopy (EGD) in patients with a positive fecal occult blood test (FOBT). Our aim was to compare the yield between EGD and colonoscopy performed in a racially diverse population with a positive FOBT.

A retrospective, cross-sectional study of FOBT positive patients who underwent EGD and colonoscopy from January 1, 1999 to November 1, 2008. Endoscopic lesions deemed responsible for GI bleeding were identified.

Two hundred and eighty-seven patients met entry criteria, among which, 63% were Asian and 81% were immigrants to the U.S. Forty-four patients had EGD findings deemed responsible for a positive FOBT, the most common being esophagitis (25.0%) and gastric ulceration (15.9%). Forty-two patients had colonoscopic findings likely responsible for a positive FOBT with the most frequent lesion being colonic polyps ≥9 mm in diameter (76.2%). Prevalence of lower and upper GI tract lesions responsible for positive FOBT was similar (14.6% vs. 15.3%, p = 0.2). There was no association between a patient reporting upper GI symptoms, or the presence of anemia and the detection of upper GI tract lesions on endoscopy. Gastric adenocarcinoma (n = 3) was as prevalent as colorectal adenocarcinoma (n = 4). All three patients with gastric adenocarcinomas were Asian (prevalence 1.6%).

In our racially diverse population evaluated for a positive FOBT, gastric adenocarcinoma was as prevalent as colorectal adenocarcinoma; however, gastric adenocarcinoma was limited to Asian patients. EGD and colonoscopy should be considered in the evaluation of patient populations similar to ours, particularly Asian immigrants.