Prognostic role of serum total cholesterol and high-density lipoprotein cholesterol in cancer survivors: A systematic review and meta-analysis

The alterations of lipid profile in cancer has been reported to be associated with cancer development. However, the prognostic value of serum lipid markers level in cancer is currently under debate. Here we performed a meta-analysis to investigate the prognostic significance of serum blood total cholesterol (TC), Triglycerides (TG), high-density lipoprotein cholesterol (HDL-C) and low-density lipoprotein cholesterol (LDL-C) for cancer.We systematically searched in PubMed and EMBASE for follow-up studies to evaluate the association between blood TC, TG, HDL-C, LDL-C and overall survival (OS) or disease-free survival (DFS) in patients with cancer. Pooled hazard ratio (HR) and 95% CIs were pooled using the random models. Subgroup and sensitivity analyses were also performed.Twenty-six studies including 24655 individuals were identified. For patients with higher TC before diagnosis, the summary HR were 0.82 (95% CI 0.75-0.90) for OS, 0.920 (95% CI, 0.849-0.997) for DFS. Patients with higher HDL-C had a 37% reduced risk of death compared with lower HDL-C (HR 0.63, 95%CI 0.47-0.86, P<0.001). As for DFS, patients with higher HDL-C level had the risk of disease relapse reduced by 35% (HR 0.65, 95% CI, 0.48-0.89, P<0.001) compared with patients with lower levels.After pooled analysis, only TC and HDL-C were significantly associated with cancer survival. Our findings demonstrate for the first time that serum TC and HDL-C was identified as a protective factor for overall survival in cancer patients.