放射治疗是继发性恶性肿瘤的长期风险。前列腺癌的外部束放射治疗（EBRT）与晚期膀胱癌的发生以及更糟糕的膀胱癌特征有关。我们旨在提供关于不同定位前列腺癌治疗后膀胱癌长期风险的更新比较。我们使用监测、流行病学和终末结果（SEER）癌症登记资料，比较了在2000年至2018年间接受根治性前列腺切除术（RP）与接受EBRT、近距离放射治疗（BT）、EBRT+BT和RP后行EBRT（RPtoEBRT）的患者的年龄匹配子群。我们的最终队列包括261,609名患者，中位随访时间为11.6年。我们的主要结果是膀胱癌诊断时间、肌层侵犯性膀胱癌诊断和膀胱癌死亡。我们使用考虑死亡作为竞争事件的特定原因的风险模型。我们还对肺癌进行了类似的分析，作为吸烟的替代指标。我们还使用卡方检验比较了放疗和RP后发生的膀胱癌中变异组织学、高级别和浸润性疾病的比例。所有放疗组均与膀胱癌诊断相关；相对于RP，EBRT、BT、EBRT+BT和RPtoEBRT的风险比（HRs）分别为1.72、1.85、1.80和1.53（所有p < 0.001）。膀胱癌死亡的HRs甚至更高：EBRT、BT和EBRT+BT的HR分别为2.39、2.57和3.02（所有p < 0.001），RPtoEBRT除外（HR 1.43，p = 0.28）。肺癌诊断也与放疗有关，但HR较低，分别为EBRT、BT、EBRT+BT和RPtoEBRT的HR为1.63、1.32、1.42和1.30（所有p < 0.001）。放疗后≥T2、≥T3和肉瘤变异膀胱癌的比例较高（所有p < 0.01）。结论：与RP治疗相比，接受放疗的患者患膀胱癌及死亡的风险增加。BT和EBRT的风险相似。放疗后的膀胱癌更容易为肉瘤变异，并表现为肌层侵犯。我们观察了患者在接受手术或放疗治疗前后的膀胱癌发生率，并发现放疗后膀胱癌的发生率较高。我们还观察到放疗后的膀胱癌往往更具侵袭性。版权所有 ©2023 Elsevier B.V. 发表。

Secondary malignancy is a long-term risk of radiation. External beam radiation therapy (EBRT) for prostate cancer treatment has been associated with later development of bladder cancer and worse bladder cancer features.We sought to provide an updated comparison of the long-term risk of bladder cancer after different localized prostate cancer treatments.Using the Surveillance, Epidemiology, and End Results (SEER) cancer registry, we compared an age-matched subset of patients who underwent radical prostatectomy (RP) with those who underwent EBRT, brachytherapy (BT), EBRT + BT, and RP followed by EBRT (RPtoEBRT) between 2000 and 2018. Our final cohort included 261 609 patients with a median follow-up of 11.6 yr.Our primary outcomes were time to bladder cancer diagnosis, muscle-invasive bladder cancer diagnosis, and bladder cancer death. We used cause-specific hazard models considering death as a competing event. A similar analysis was performed on lung cancer, as a surrogate marker for smoking. We also compared proportions of variant histology, high-grade, and invasive disease among bladder cancers that occurred after radiation versus RP using chi-square testing.All radiation groups were associated with bladder cancer diagnosis; hazard ratios (HRs) were 1.72, 1.85, 1.80, and 1.53 for EBRT, BT, EBRT + BT, and RPtoEBRT, respectively, using RP as a referent (all p < 0.001). HRs for bladder cancer death were even higher: 2.39, 2.57, and 3.02 for EBRT, BT, and EBRT + BT, respectively (all p < 0.001), except for RPtoEBRT (HR 1.43, p = 0.28). Lung cancer diagnosis was also associated with radiation but at lower HRs-1.63, 1.32, 1.42, and 1.30 for EBRT, BT, EBRT + BT, and RPtoEBRT, respectively (all p < 0.001). There were a higher proportion of ≥T2, ≥T3, and sarcomatoid variant bladder cancers after radiation (all p < 0.01) CONCLUSIONS: The risk of developing and dying from bladder cancer is increased in patients treated with radiation compared with those treated with RP. The risk was similar for BT and EBRT. Bladder cancers after radiation are more likely to be sarcomatoid variant and present as muscle invasive.We observed the rates of bladder cancer after patients had undergone surgery or radiation for prostate cancer, and found higher rates of bladder cancer after radiation. We also observed that bladder cancers that occur after radiation tend to be more aggressive.Copyright © 2023. Published by Elsevier B.V.