Department of Gastrointestinal Surgery, Affiliated Hospital of Yangzhou University, Yangzhou, 225100, People's Republic of China.
Department of Gastrointestinal Surgery, Northern Jiangsu People's Hospital, Clinical Medical School, Affiliated Hospital of Yangzhou University, Yangzhou, 225002, People's Republic of China.
World J Surg Oncol. 2020 Feb 4;18(1):30. doi: 10.1186/s12957-020-1805-3.
Clinically, when the diagnosis of colorectal cancer is clear, patients are more concerned about their own prognosis survival. Special population with high risk of accidental death, such as elderly patients, is more likely to die due to causes other than tumors. The main purpose of this study is to construct a prediction model of cause-specific death (CSD) in elderly patients using competing-risk approach, so as to help clinicians to predict the probability of CSD in elderly patients with colorectal cancer.
The data were extracted from Surveillance, Epidemiology, and End Results (SEER) database to include ≥ 65-year-old patients with colorectal cancer who had undergone surgical treatment from 2010 to 2016. Using competing-risk methodology, the cumulative incidence function (CIF) of CSD was calculated to select the predictors among 13 variables, and the selected variables were subsequently refined and used for the construction of the proportional subdistribution hazard model. The model was presented in the form of nomogram, and the performance of nomogram was bootstrap validated internally and externally using the concordance index (C-index).
Dataset of 19,789 patients who met the inclusion criteria were eventually selected for analysis. The five-year cumulative incidence of CSD was 31.405% (95% confidence interval [CI] 31.402-31.408%). The identified clinically relevant variables in nomogram included marital status, pathological grade, AJCC TNM stage, CEA, perineural invasion, and chemotherapy. The nomogram was shown to have good discrimination after internal validation with a C-index of 0.801 (95% CI 0.795-0.807) as well as external validation with a C-index of 0.759 (95% CI 0.716-0.802). Both the internal and external validation calibration curve indicated good concordance between the predicted and actual outcomes.
Using the large sample database and competing-risk analysis, a postoperative prediction model for elderly patients with colorectal cancer was established with satisfactory accuracy. The individualized estimates of CSD outcome for the elderly patients were realized.
临床上，当结直肠癌的诊断明确后，患者更关心自身的预后生存情况。对于意外死亡风险较高的特殊人群，如老年患者，其更有可能因肿瘤以外的原因而死亡。本研究旨在采用竞争风险分析方法构建老年结直肠癌患者的特异性死因（CSD）预测模型，以便帮助临床医生预测老年结直肠癌患者发生 CSD 的概率。
从监测、流行病学和最终结果（SEER）数据库中提取 2010 年至 2016 年接受手术治疗的年龄≥65 岁的结直肠癌患者数据。采用竞争风险方法，计算 CSD 的累积发生率函数（CIF），从 13 个变量中筛选预测因素，对筛选出的变量进行精炼并用于构建比例亚分布风险模型。该模型以列线图的形式呈现，通过一致性指数（C 指数）对内、外部进行内部和外部验证。
最终纳入符合条件的 19789 例患者的数据集进行分析。CSD 的 5 年累积发生率为 31.405%（95%置信区间[CI]31.402-31.408%）。列线图中确定的具有临床意义的变量包括婚姻状况、病理分级、AJCC TNM 分期、CEA、神经周围侵犯和化疗。内部验证后，该列线图的 C 指数为 0.801（95%CI0.795-0.807），外部验证的 C 指数为 0.759（95%CI0.716-0.802），均具有良好的区分度。内部和外部验证的校准曲线均表明，预测结果与实际结果具有良好的一致性。
利用大样本数据库和竞争风险分析，建立了一种用于老年结直肠癌患者的术后预测模型，具有较好的准确性。实现了对老年患者 CSD 结局的个体化评估。
