Preoperative serum total cholesterol is a predictor of prognosis in patients with renal cell carcinoma: a meta-analysis of observational studies

ABSTRACT Purpose Several studies have demonstrated the strong correlation between the levels of preoperative serum total cholesterol (TC) and the survival of patients with surgically treated renal cell carcinoma (RCC). However, this association remains controversial. We performed a meta-analysis of published reports to evaluate the prognostic significance of the preoperative serum TC levels for patients with surgically treated RCC. Material and Methods The databases from MEDLINE (via PubMed), Embase, Web of Science and Cochrane Library were systematically searched to identify the eligible studies published before August 2019. Multivariate adjusted hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated through inverse variance by using random-effects models. Results Nine cohort studies comprising 15.609 patients were identified. Low preoperative serum TC levels were associated with poor cancer-specific survival (CSS; HR=0.98, 95% CI: 0.97-0.99; P=0.005; I2=74.2%) and progression-free survival (PFS; HR=0.69, 95% CI: 0.49-0.98; P=0.036; I2=80%) in patients with surgically treated RCC. However, no significant association was observed between low preoperative serum TC levels and shorter overall survival (HR=0.93, 95% CI: 0.87-1.00; P=0.057; I2=86.2%). Sensitivity analyses validated the reliability and rationality of the results. Conclusions Preoperative serum TC level is an independent poor prognostic factor for patients with surgically treated RCC, with lower levels associated with worse CSS and PFS. Hence, this parameter may provide additional guidance in the selection of therapeutic strategies to improve prognosis, considering that cholesterol is a broadly applied routine marker in clinical practice.摘要 目的：已有多项研究证实，接受手术治疗的肾细胞癌（renal cell carcinoma, RCC）患者术前血清总胆固醇（total cholesterol, TC）水平与生存结局存在显著相关性，但该关联仍存在争议。本研究通过对已发表文献进行荟萃分析，旨在评估术前血清总胆固醇水平对接受手术治疗的肾细胞癌患者的预后价值。材料与方法：系统检索MEDLINE（通过PubMed）、Embase、Web of Science及Cochrane Library数据库，筛选2019年8月之前发表的符合纳入标准的研究。采用随机效应模型通过逆方差法计算校正后的多变量风险比（hazard ratio, HR）及95%置信区间（confidence interval, CI）。结果：共纳入9项队列研究，涉及15609例患者。分析显示，术前血清总胆固醇水平较低与接受手术治疗的肾细胞癌患者较差的癌症特异性生存（cancer-specific survival, CSS；HR=0.98，95%CI：0.97~0.99；P=0.005；I²=74.2%）及无进展生存（progression-free survival, PFS；HR=0.69，95%CI：0.49~0.98；P=0.036；I²=80%）显著相关。但术前血清总胆固醇水平较低与总生存期缩短无显著关联（HR=0.93，95%CI：0.87~1.00；P=0.057；I²=86.2%）。敏感性分析验证了本研究结果的可靠性与合理性。结论：术前血清总胆固醇水平是接受手术治疗的肾细胞癌患者的独立不良预后因素，较低的总胆固醇水平与更差的癌症特异性生存及无进展生存相关。鉴于胆固醇是临床实践中广泛应用的常规检测指标，该参数可为治疗策略的选择提供额外指导，以改善患者预后。