Section of Occupational Medicine, Department of Medical and Surgical Sciences, University of Bologna, Bologna, Italy.
Cancer Causes Control. 2013 Aug;24(8):1535-45. doi: 10.1007/s10552-013-0230-0. Epub 2013 May 24.
To investigate the association between external beam radiotherapy (EBRT) for prostate cancer and mesothelioma using data from the US Surveillance, Epidemiology, and End Results (SEER) cancer registries.
We analyzed data from the SEER database (1973-2009). We compared EBRT versus no radiotherapy. Incidence rate ratios (IRR) and 95 % confidence intervals (95 % CI) of mesothelioma among prostate cancer patients were estimated with multilevel Poisson models adjusted by race, age, and calendar year. Confounding by asbestos was investigated using relative risk of mesothelioma in each case's county of residence as a proxy for asbestos exposure.
Four hundred and seventy-one mesothelioma cases (93.6 % pleural) occurred in 3,985,991 person-years. The IRR of mesothelioma was increased for subjects exposed to EBRT (1.28; 95 % CI 1.05, 1.55) compared to non-irradiated patients, and a population attributable fraction of 0.49 % (95 % CI 0.11, 0.81) was estimated. The IRR increased with latency period: 0-4 years, IRR 1.08 (95 % CI 0.81, 1.44); 5-9 years, IRR 1.31 (95 % CI 0.93, 1.85); ≥10 years, IRR 1.59 (95 % CI 1.05, 2.42). Despite the fairly strong evidence of association with EBRT, the population attributable rate of mesothelioma was modest-3.3 cases per 100,000 person-years. The cumulative incidence of mesothelioma attributable to EBRT was 4.0/100,000 over 5 years, 24.5/100,000 over 10 years, and 65.0/100,000 over 15 years.
Our study provides evidence that EBRT for prostate cancer is a small but detectable risk factor for mesothelioma. Patients should be advised of risk of radiation-induced second malignancies.
利用美国监测、流行病学和最终结果（SEER）癌症登记处的数据，研究前列腺癌外照射放疗（EBRT）与间皮瘤之间的关系。
我们分析了 SEER 数据库（1973-2009 年）的数据。我们比较了 EBRT 与无放疗。使用多水平泊松模型，通过种族、年龄和日历年来调整发病率比值（IRR）和 95%置信区间（95%CI），估计前列腺癌患者中间皮瘤的发生率。使用每个病例居住地的县的间皮瘤相对风险作为石棉暴露的替代物，调查石棉混杂的影响。
在 3985991 人年中，471 例间皮瘤病例（93.6%为胸膜）发生。与未接受放疗的患者相比，接受 EBRT 照射的患者间皮瘤的 IRR 升高（1.28；95%CI 1.05，1.55），估计人群归因分数为 0.49%（95%CI 0.11，0.81）。IRR 随潜伏期而增加：0-4 年，IRR 1.08（95%CI 0.81，1.44）；5-9 年，IRR 1.31（95%CI 0.93，1.85）；≥10 年，IRR 1.59（95%CI 1.05，2.42）。尽管 EBRT 有相当强的关联证据，但间皮瘤的人群归因率适中-每 100000 人年 3.3 例。EBRT 引起的间皮瘤累积发生率为 5 年内 4.0/100000 人，10 年内 24.5/100000 人，15 年内 65.0/100000 人。
我们的研究提供了证据，证明前列腺癌的 EBRT 是间皮瘤的一个小但可检测到的危险因素。应告知患者辐射引起的第二恶性肿瘤的风险。
