术前外周血血小板/淋巴细胞比值相关列线图模型预测胃癌患者术后无病生存期:一项双中心回顾性研究

Value of a preoperative peripheral platelet-to-lymphocyte ratio ralated nomogram model predicting postoperative disease-free survival in patients with gastric cancer:a two-center retrospective study

目的探讨外周血血小板/淋巴细胞比值(platelet-to-lymphocyte ratio,PLR)对胃癌患者术后无病生存期(disease-free survival,DFS)的影响,并构建列线图模型预测胃癌患者术后DFS。方法回顾性纳入2011年12月至2019年12月在复旦大学附属肿瘤医院行胃癌根治术的3112例患者,随机分为训练组(n=2178)和内部验证组(n=934)。选择2010年至2018年广西医科大学附属肿瘤医院诊治的280例胃癌患者作为外部验证组。采用单因素和多因素Cox回归分析筛选影响训练组患者术后DFS的危险因素,建立预测胃癌患者术后1、3、5年DFS的列线图模型。采用C指数和校准曲线评估模型的辨别和校准能力,通过内部验证组和外部验证组检验模型的准确性。结果多因素Cox回归分析显示,TNM分期Ⅱ~Ⅲ期(Ⅱ期:HR=1.64,95%CI 1.29~1.97,P<0.001;Ⅲ期:HR=2.52,95%CI 2.20~2.82,P<0.001)、癌胚抗原(carcinoembryonic antigen,CEA)>5.2μg/L(HR=1.48,95%CI 1.12~1.97,P=0.007)、外周血PLR>114.21(HR=1.34,95%CI 1.02~1.78,P=0.036)是胃癌患者术后复发和转移的独立相关因素。基于外周血PLR、TNM分期、CEA建立预测胃癌患者术后1、3、5年DFS的列线图模型,C指数为0.734(P=0.013),校准曲线预测的1、3、5年DFS与实际DFS一致性较好;模型预测1、3、5年DFS的ROC曲线下面积分别为0.716、0.773、0.752。将列线图模型应用于内部验证组和外部验证组,结果显示模型能有效区分不同预后患者。结论术前外周血PLR是影响胃癌患者术后复发和转移的独立相关因素,其与TNM分期、CEA联合构建的列线图模型能有效预测胃癌患者的术后DFS。

Objective To explore the effect of the peripheral blood platelet-to-lymphocyte ratio(PLR)on postoperative disease-free survival(DFS)in patients with gastric cancer,and to construct a nomogram model to predict postoperative DFS in gastric cancer patients.Methods A total of 3112 patients who underwent radical gastrectomy in Shanghai Cancer Center,Fudan University from December 2011 to December 2019 were retrospectively collected and randomly divided into training group(n=2178)and internal verification group(n=934).A total of 280 patients with gastric cancer in Guangxi Medical University Cancer Hospital from 2010 to 2018 were collected as external verification group.Univariate and multivariate Cox regression analysis were used to screen the risk factors of postoperative DFS in the training group,and a nomogram model was established to predict 1-,3-and 5-year DFS in patients with gastric cancer.C index and calibration curve were used to evaluate the discrimination and calibration ability of the model.The accuracy of the model was verified by internal verification group and external verification group.Results Multivariate Cox regression analysis of the training group showed that TNM staging Ⅱ-Ⅲ(Ⅱ:HR=1.64,95%CI 1.29-1.97,P<0.001;Ⅲ:HR=2.52,95%CI 2.20-2.82,P<0.001),carcinoembryonic antigen(CEA)>5.2μg/L(HR=1.48,95%CI 1.12-1.97,P=0.007),peripheral blood PLR>114.21(HR=1.34,95%CI 1.02-1.78,P=0.036)were independent associated factors for postoperative recurrence or metastasis in patients with gastric cancer.The nomogram model was established based on TNM staging,CEA and peripheral blood PLR.The C-index was 0.734(P=0.013),and the area under curve(AUC)of the model predicting 1-,3-and 5-year DFS was 0.716,0.773 and 0.752,respectively.The model also performed well in the internal validation group and the external validation group.Conclusions Preoperative peripheral blood PLR is an independent factor for predicting postoperative recurrence or metastasis in patients with gastric cancer,and the nomogram model established by PLR,TNM staging and CEA can accurately and efficiently predict postoperative DFS of patients.