Division of Urology, Duke University Medical Center, Durham, NC 27710, USA.
Urol Oncol. 2013 Nov;31(8):1628-34. doi: 10.1016/j.urolonc.2012.04.006. Epub 2012 May 9.
Prostate radiotherapy (RT) has been associated with an increased risk of bladder cancer (CaB). However it is unknown how prior RT affects the stage, grade, and histology of secondary CaB. While irradiated patients have adverse surgical outcomes, how RT affects survival is also unknown. We sought to determine how RT for prostate cancer (CaP) affects the characteristics and outcomes of secondary CaB.
A retrospective review of 275,200 cases of clinically localized CaP submitted to the Surveillance, Epidemiology, and End Results (SEER) database between 1988 and 2007 was performed. CaP treatment was stratified by radical prostatectomy (RP) alone, RT, or RP + RT. Diagnosis of CaB at least 1 year after CaP, and CaB death were the primary outcomes. The stage, grade, and histology of CaB of patients exposed to RT or RP were compared. A competing risks multivariable survival analysis was performed to determine the effect of RT on CaB-specific mortality.
CaP patients treated with any RT were 1.70 times as likely to develop CaB (95% CI 1.57-1.86, P < 0.001) compared with RP alone. CaB in men who had RT were more likely non-urothelial (6.4% vs. 3.8%, P = 0.004), trigonal (6.9% vs. 5.4%, P = 0.012), and carcinoma in-situ (CIS) (9.2% vs. 7.0%, P < 0.001) compared with RP. RT increased CaB-specific mortality (HR = 1.30, P = 0.02), which remained significant when adjusted for CaB features (HR = 1.28, P = 0.05).
Patients with localized CaP treated with RT have a higher risk of CaB. CaB after RT is more likely to be located at the trigone and contain CIS. Patients with CaB after RT have decreased cancer-specific survival compared with those undergoing RP alone.
前列腺放射治疗（RT）与膀胱癌（CaB）风险增加有关。然而，先前的 RT 如何影响继发性 CaB 的分期、分级和组织学尚不清楚。虽然接受过放疗的患者手术结果不佳，但 RT 如何影响生存率也尚不清楚。我们试图确定前列腺癌（CaP）的 RT 如何影响继发性 CaB 的特征和结局。
对 1988 年至 2007 年间向监测、流行病学和最终结果（SEER）数据库提交的 275200 例临床局限性 CaP 病例进行了回顾性分析。CaP 治疗分为单纯前列腺切除术（RP）、RT 或 RP+RT。至少在 CaP 后 1 年诊断出 CaB，以及 CaB 死亡是主要结果。比较了接受 RT 或 RP 治疗的患者的 CaB 分期、分级和组织学。采用竞争风险多变量生存分析确定 RT 对 CaB 特异性死亡率的影响。
与单纯 RP 相比，接受任何 RT 治疗的 CaP 患者发生 CaB 的可能性高 1.70 倍（95%CI 1.57-1.86，P<0.001）。接受 RT 的男性的 CaB 更有可能是非尿路上皮性（6.4%比 3.8%，P=0.004）、三角区（6.9%比 5.4%，P=0.012）和原位癌（CIS）（9.2%比 7.0%，P<0.001）。与 RP 相比，RT 增加了 CaB 特异性死亡率（HR=1.30，P=0.02），当调整 CaB 特征后，这一结果仍然具有统计学意义（HR=1.28，P=0.05）。
接受 RT 治疗的局限性 CaP 患者发生 CaB 的风险更高。RT 后发生的 CaB 更可能位于三角区且包含 CIS。与单纯 RP 相比，接受 RT 后发生 CaB 的患者的癌症特异性生存率降低。
