RT Journal Article ID 31c804be7cd0bf7a A1 Zhao, Fuxing A1 Yuan, Xinyue A1 Ren, Dengfeng A1 Shen, Guoshuang A1 Wang, Ziyi A1 Zheng, Fangchao A1 Ahmad, Raees A1 Ma, Zhijun A1 Zhao, Jiuda T1 Predicting the Efficacy of 5-Fluorouracil–Based Adjuvant Chemotherapy in Gastric Cancer by Microsatellite Instability: A Meta-Analysis JF Journal of Environmental Pathology, Toxicology and Oncology JO JEP(T) YR 2019 FD 2019-01-18 VO 38 IS 1 SP 21 OP 28 K1 gastric cancer K1 microsatellite instability K1 fluorouracil AB Microsatellite instability (MSI) implies the deletion of mismatch repair genes caused by DNA methylation or gene mutation. MSI is a good predictor for efficacy of 5-fluorouracil (FU)–based chemotherapy in the treatment of colorectal cancer. Some gastric cancer studies have reported that MSI has no apparent impact on prognosis after patients receive 5-FU–based adjuvant chemotherapy. However, other studies suggest that high-frequency MSI (MSI-H) status reduced survival in patients receiving 5-FU–based adjuvant chemotherapy. Thus, the correlation between MSI status and efficacy of 5-FU–based adjuvant chemotherapy for gastric cancer remains controversial. We performed a PubMed, Embase, and Cochrane search to retrieve studies that explore the correlation between MSI status and 5-FU–based adjuvant chemotherapy efficacy in gastric cancer. After extracting 65 potentially eligible studies, four were ultimately included in this meta-analysis using Stata software (ver. 12.0). For each study, we estimated the hazard ratio (HR) value for overall survival (OS), and HR was extracted per the survival curve in the studies. Heterogeneity was estimated using the random-effects model. Overall, 1174 patients after operation were included: 84 patients were classed as MSI-H and 1090 as microsatellite stable (MSS)/low-frequency MSI (MSI-L). For the four studies, the overall estimate of HR for OS between MSI-H and MSS/MSI-L groups was 1.90 (95% confidence interval: 0.91–3.93; p = 0.08). We found no correlation to exist between MSI status and efficacy of 5-FU–based adjuvant chemotherapy for gastric cancer. Although MSI can effectively predict efficacy of 5-FU–based chemotherapy in patients with colorectal cancer, the correlation between MSI status and efficacy of 5-FU–based adjuvant chemotherapy for gastric cancer remains controversial. This meta-analysis suggests that MSI status is unrelated to efficacy of 5-FU–based adjuvant chemotherapy in gastric cancer, and more prospective clinical studies are needed to further investigate predictive value of MSI status in patients with gastric cancer who, after operation, receive 5-FU–based adjuvant chemotherapy. PB Begell House LK https://www.dl.begellhouse.com/journals/0ff459a57a4c08d0,4b309b253eb144f8,31c804be7cd0bf7a.html