Risk of gastric cancer among patients with gastric intestinal metaplasia

Plenty of studies have assessed the association between intestinal metaplasia (IM) and gastric cancer risk, while the results were inconsistent. We aimed to assess the risk of gastric cancer among patients with IM. Systematic literature searches were conducted in PubMed, Embase and Cochrane databases. Baseline characteristics and outcomes from the included studies were extracted independently by two investigators. Either a fixed-effects or a random-effects model was used to composite the pooled OR for gastric cancer risk. Finally, a total of 21 studies, which comprised 402,636 participants and 4,535 gastric cancer patients, were finally included in the current meta-analysis. Compared with those participants without IM, IM patients were at a higher risk of gastric cancer (pooled OR=3.58, 95% CI 2.71-4.73). We observed that incomplete IM (pooled OR=9.48, 95% CI 4.33-20.78) but not complete IM (pooled OR=1.55, 95% CI 0.91-2.65) was significantly associated with a higher gastric cancer risk. Besides, it appeared that gastric cancer risk was higher among patients with IM in the corpus (pooled OR=7.39, 95% CI 4.94-11.06) than those with IM in the antrum only (pooled OR=4.06, 95% CI 2.79-5.91). And the pooled ORs for gastric noncardia cancer and gastric cardia cancer were 4.98 (95% CI 3.12-7.95) and 1.93 (95% CI 1.15-3.24), respectively. In conclusion, patients with IM were at a higher risk of gastric cancer, especially for incomplete IM and IM in the corpus. The current evidence supports the use of IM subtypes in the surveillance of gastric cancer.