| Description: | A total of ten studies reported the OS of 1,052 patients, according to MALAT1 expression levels. Heterogeneity analysis revealed no heterogeneity among these studies, therefore, the fixed-effects model (I2, 0.0%; P=0.528) was assessed in the meta-analysis. Overall, the pooled results confirmed a significant association between high MALAT1 expression and poor OS in digestive system malignancies, with a HR value of 1.62 (95% CI, 1.35–1.88; P<0.001; Fig. 2). Although there was no significant heterogeneity among the studies, a subgroup meta-analysis was conducted on tumor type, country, sample size and analysis type (Table III). A significant association was identified between the expression of MALAT1 and the OS of patients with digestive system malignant tumors in China (HR, 1.63; 95% CI, 1.34–1.91). The association between MALAT1 and OS was significant in studies with a sample size ≥100 (HR, 1.57; 95% CI, 1.27–1.88; P<0.001) and <100 (HR, 1.76; 95% CI, 1.21–2.31; P<0.001). Furthermore, MALAT1 was also identified to be significantly associated with OS of patients in studies with multivariate analysis (HR, 1.51; 95% CI, 1.19–1.84; P<0.001) and non-multivariate analysis (HR, 1.84; 95% CI, 1.37–2.31; P<0.001). Furthermore, sensitivity analysis indicated the robustness of the meta-analysis results (Fig. 3). |