Association between pretreatment serum apolipoprotein a1 and prognosis of solid tumors in Chinese population: A systematic review and meta-analysis

Abstract

Background/Aims: Serum apolipoprotein A1 (apoA1) has been reported to be abnormally expressed in several malignancies. However, the prognostic role of apoA1 in solid tumors is still controversial. We conducted this meta-analysis to obtain a more accurate evaluation of prognostic significance of apoA1 in Chinese patients with solid tumors. Methods: A comprehensive literature search of electronic databases was carried out up to August 2018. We included studies investigating the association between pretreatment serum apoA1 level and clinicopathological features, including survival outcomes, in solid tumors. Hazard ratios (HRs) and odds ratio (ORs) with 95% confidence intervals (CIs) were applied as effect size estimates. Results: A total of 13 studies and 8052 patients were included in our meta-analysis. Elevated level of pretreatment serum apoA1 was markedly associated with an improved OS (pooled HR = 0.608, 95% CI = 0.557 - 0.665, P < 0.001). The statistical significances were observed in all cancer types, including digestive system malignancies (pooled HR = 0.633; 95% CI = 0.550-0.727; P < 0.001), urinary system cancers (pooled HR = 0.471; 95% CI = 0.352-0.630; P < 0.001), nasopharyngeal cancer (pooled HR = 0.642; 95% CI = 0.538-0.766; P < 0.001) and non-small cell lung cancer (pooled HR = 0.526; 95% CI = 0.329-0.841; P = 0.007), but not in breast cancer (pooled HR = 0.573; 95% CI = 0.266-1.246; P = 0.155). Meanwhile, cancer patients with a low level of serum apoA1 suffered an unfavorable DFS (pooled HR = 0.714, 95% CI = 0.603 - 0.845, P < 0.001). Moreover, abnormal serum apoA1 was significantly correlated to tumor size (pooled OR = 0.640, 95% CI = 0.475 - 0.863, P = 0.003), tumor differentiation (pooled HR = 0.724, 95% CI = 0.565 - 0.929, P = 0.011), and tumor stage (pooled HR = 0.493, 95% CI = 0.384 - 0.633, P < 0.001). Conclusion: Elevated level of pretreatment serum apoA1 was significantly associated with longer survival in patients with solid tumors. Pretreatment serum apoA1 could serve as a novel positive factor for malignant patient prognosis in Chinese population.