Backgrounds: Plenty of studies have been conducted to explore the prognostic value of LncRNA AFAP1-AS1 in various cancers, however, with contradictory outcomes. The aim of the current study was to explore the prognostic value of high LncRNA AFAP1-AS1 expression in various cancers.

Methods: PubMed, EMBASE, Web of Science, Cochrane library, China National Knowledge Internet (CNKI) and Wan-fang database were comprehensively retrieved, and all the relevant studies were included into the study.

Results: A total of 21 studies involving 2179 patients were finally included into the systematic review and meta-analysis. Compared to low LncRNA AFAP1-AS1 expression, high LncRNA AFAP1-AS1 expression was significantly related to shorter OS (HR = 2.02, 95%CI = 1.51-2.70, P < 0.001; I² = 78%), DFS(HR = 1.80, 95%CI = 1.16-2.80, P = 0.009; I² = 0%), RFS (HR = 2.90, 95%CI = 1.79-4.69, P < 0.001; I² = 38%)and PFS(HR = 2.18, 95%CI = 1.62-2.92, P < 0.001; I² = 0%) in patients with various cancers. Besides, high LncRNA AFAP1-AS1 expression was significantly associated with smoking (P < 0.001), advanced clinical stage (P < 0.001), larger tumor size (P < .001), earlier tumor metastasis (P < 0.001), earlier lymph nodal involvement (P = 0.002) and vascular invasion (P < 0.001) in various cancers.

Conclusions: Cancer patients with high LncRNA AFAP1-AS1 expression had shorter OS, DFS, RFS and PFS compared to those with low expression. Moreover, high LncRNA AFAP1-AS1 expression was significantly related to advanced clinical stage, larger tumor size, earlier tumor metastasis, earlier lymph nodal involvement and vascular invasion. High LncRNA AFAP1-AS1 expression was an unfavorable prognostic factor in various cancers.