Incidence Rate of Gastric Cancer Adenocarcinoma in Patients with Gastric Dysplasia: A Systematic Review and Meta-Analysis

Several studies have reported the risk of progression to gastric adenocarcinoma (GAC) in patients with gastric dysplasia (GD); however, the findings are controversial. We performed a systematic review and meta-analysis to study the incidence rate of GAC among patients with GD. Using a comprehensive search strategy, we systematically searched online databases including PubMed, Scopus, EMBASE, Cochrane Library, and Web of Science databases for identifying all relevant original articles through inception until July 2018. Cochran Q and I² tests were used to assess heterogeneities between included studies. The incidence rates of GAC and their corresponding 95% confidence intervals (CIs) were pooled using random-effect or fixed-effect models. Of the 1980 retrieved records, 30 eligible articles (61 studies) were included. The overall pooled incidence rate of GAC was 40.36 (95% CI, 27.08-55.71; I², 96.0%) cases per 1000 person-years in patients with GD. Subgroup analysis according to the type of GD indicated the highest incidence rate of GAC was 186.40 (95% CI, 106.63-285.60; I², 94.6%) per 1000 person-years among patients with high-grade dysplasia (HGD) lesions. Although the incidence rates of GAC in low-grade dysplasia (LGD) lesions and in nonclassified lesions were 11.25 (95% CI, 3.91-21.22; I², 89.3%), and 1.40 (95% CI, 0.00-9.71; I², 78.8%), respectively. Compared with patients with LGD lesions, progression rate from GD to GAC was roughly 16 times greater in patients with HGD lesions. As the majority of patients with GAC are diagnosed in an advanced stage our study suggests strict management of HGD lesions to prevent GAC.