The aim of this study is to determine the incidence trends of urothelial cancer of the bladder (UCB) and to develop a nomogram for predicting the cancer-specific survival (CSS) of postsurgery UCB at a population-based level based on the SEER database. The age-adjusted incidence of UCB diagnosed from 1975 to 2016 was extracted, and its annual percentage change was calculated and joinpoint regression analysis was performed. A nomogram was constructed for predicting the CSS in individual cases based on independent predictors. The predictive performance of the nomogram was evaluated using the consistency index (C-index), net reclassification index (NRI), integrated discrimination improvement (IDI), a calibration plot and the receiver operating characteristics (ROC) curve. The incidence of UCB showed a trend of first increasing and then decreasing from 1975 to 2016. However, the overall incidence increased over that time period. The age at diagnosis, ethnic group, insurance status, marital status, differentiated grade, AJCC stage, regional lymph nodes removed status, chemotherapy status, and tumor size were independent prognostic factors for postsurgery UCB. The nomogram constructed based on these independent factors performed well, with a C-index of 0.823 and a close fit to the calibration curve. Its prediction ability for CSS of postsurgery UCB is better than that of the existing AJCC system, with NRI and IDI values greater than 0 and ROC curves exhibiting good performance for 3, 5, and 8 years of follow-up. The nomogram constructed in this study might be suitable for clinical use in improving the clinical predictive accuracy of the long-term survival for postsurgery UCB.

中文翻译：

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膀胱尿路上皮癌的发病趋势和生存预测：一项基于人群的研究

本研究的目的是确定膀胱尿路上皮癌 (UCB) 的发病率趋势，并基于 SEER 数据库开发一个列线图，用于在基于人群的水平上预测术后 UCB 的癌症特异性存活率 (CSS)。提取1975年至2016年诊断的UCB的年龄调整发病率，计算其年百分比变化并进行joinpoint回归分析。构建了一个列线图，用于基于独立预测变量预测个别情况下的 CSS。使用一致性指数 (C-index)、净重分类指数 (NRI)、综合鉴别改进 (IDI)、校准图和接收者操作特征 (ROC) 曲线评估列线图的预测性能。1975-2016年UCB的发病率呈先上升后下降的趋势，但总体发病率在此期间呈上升趋势。诊断年龄、种族、保险状况、婚姻状况、分化等级、AJCC 分期、区域淋巴结切除状况、化疗状况和肿瘤大小是术后 UCB 的独立预后因素。基于这些独立因素构建的列线图表现良好，C 指数为 0.823，与校准曲线非常接近。其对术后UCB的CSS预测能力优于现有的AJCC系统，NRI和IDI值均大于0，ROC曲线在3、5、8年的随访中表现良好。