The detailed results are provided in Table 3, and we found that lower Apo A-I was associated with poor CSS (HR: 0.47, 95% CI: 0.19–0.76, p < 0.01) in cancers, and low ApoA-I level was a prognostic factor for inferior TTR (HR: 0.43, 95% CI: 0.29–0.58, p < 0.01) in HCC, LRFS (HR: 0.58, 95% CI: 0.42–0.74, p < 0.01) and DMFS (HR: 0.65, 95% CI: 0.41–0.89, p < 0.01) in NPC, and DFS (HR: 0.64, 95% CI: 0.43–0.84, p < 0.01) in various cancers. Here, APOA1 is linked to hepatocellular carcinoma.