Studies of Populations Exposed to Occupational Sources o

美国放射技术人员队列中的癌症和其他死亡风险1982年，辐射流行病学分支机构(REB)与明尼苏达大学合作，在全国范围内对146,022名美国放射技术人员的癌症发病率和死亡率进行了队列研究。队列中73%是女性，这为研究长期低至中等剂量辐射暴露对乳腺癌和甲状腺癌的影响提供了难得的机会，这两个部位是女性辐射致癌最敏感的两个部位。其他癌症和非癌症严重疾病的结果也正在评估与长期低到中等剂量的暴露有关。2001年以来的主要发现包括：乳腺癌的死亡风险随着1950年之前工作年限的增加而显著增加；脑血管疾病的死亡率随着第一年工作年限的增加和1950年之前工作年限的增加而显著增加；乳腺癌(女性)、甲状腺癌和黑色素瘤的发病风险与SEER相比显著增加，并经无反应调整。内部队列分析显示，1940年以前工作的人患乳腺癌的风险显著增加，1950年以前工作的人患黑色素瘤和非黑色素瘤皮肤癌的风险显著增加，1950年以前工作5年的人患非慢性淋巴细胞性白血病的风险略有增加，1960年以前工作的人患甲状腺癌的风险建议增加，而肺癌的风险没有发现。对ATM基因的突变分析表明，这些基因的突变不太可能解释遗传性乳腺癌的很大一部分原因，但一些低频率的多态可能会增加乳腺癌的风险。在过去的一年里，我们完成了关于癌症和其他医疗结果、特定日历的就业因素(所执行的程序和相关保护措施)以及癌症风险因素的第三次全面调查。在102,000名已知的第一次或第二次调查应答者中，有近74,000人(72%)参加了第三次调查。我们发表了第一份乳腺癌的半定量辐射风险评估报告。完成了对乳腺癌和几种基因途径(如ATM、双链断裂修复、碱基切除修复、细胞凋亡)的遗传多态的研究，并提交了手稿。从第三次调查中发现的另外756例乳腺癌患者中采集了静脉穿刺血样本，并启动了邮寄DNA指刺血样采集的试点研究。此外，我们还完成了3.5版剂量测量系统的开发。使用单独的FISH测量对152个终身剂量估计进行证实，使我们有信心使用版本3.5的剂量估计进行剂量-反应分析并继续进行出版。俄罗斯核工作者暴露于钚和长期外部辐射中的癌症死亡率正在研究中，因为他们构成了长期暴露于高剂量外部辐射和暴露于钚的独特职业组。暴露于外部辐射的剂量-反应关系被证明是白血病、肺癌、肝癌和骨癌(作为单一类别分析)以及除肺癌、骨癌和肝癌以外的所有实体癌症的死亡率。按性别、暴露年龄和暴露以来的时间划分的风险模式通常与在原子弹幸存者中观察到的相似。死亡率分析还清楚地表明，内部暴露于钚会导致肺癌、肝癌和骨癌的风险过高，这些地方从钚获得的剂量最高。最近进行的肺癌死亡率的剂量-反应分析表明，钚对肺的内部剂量和外部剂量都有显著的相关性(p>0.001)。

Cancer and Other Mortality Risks in a Cohort of U.S. Radiologic TechnologistsIn 1982, the Radiation Epidemiology Branch (REB), in collaboration with the University of Minnesota, initiated a nationwide cohort study of cancer incidence and mortality among 146,022 U. S. radiologic technologists. The cohort is 73% female, offering a rare opportunity to study effects of protracted low- to moderate-dose radiation exposure on breast and thyroid cancer, the two most sensitive organ sites for radiation carcinogenesis in women. Other cancer and non-cancer serious disease outcomes are also being evaluated in relation to protracted low-to-moderate dose exposures. Major findings since 2001 include: Mortality risks for breast cancer increased significantly with increasing number of years worked before 1950; mortality from cerebrovascular diseases increased significantly with earlier year first worked and with number of years worked before 1950; significantly elevated risks were found for incident cancers of the breast (female), thyroid, and melanoma compared to SEER and adjusted for non-response. Internal cohort analyses revealed significantly elevated incidence risks for breast cancer associated with working before 1940, melanoma and non-melanoma skin cancers related to working before 1950, modest elevated risk for non-chronic lymphocytic leukemia related to working >5 years before 1950, and a suggested elevated risk for thyroid cancer with working before 1960, while no associations were found for lung cancer. Mutational analysis of the ATM genes revealed that mutations in these genes are unlikely to account for a significant fraction of inherited breast cancer but a few low-frequency polymorphisms may increase breast cancer risk. During the past year, we completed a third comprehensive survey of cancer and other medical outcomes, calendar-specific employment factors (procedures performed and related protection practices), and cancer risk factors. Nearly 74,000 of 102,000 (72%) known living first or second survey responders participated in the third survey. We published our first semi-quantitative radiation risk assessment for breast cancer. Studies of breast cancer and genetic polymorphisms in several gene pathways (e.g. ATM, double strand break repair, base excision repair, apoptosis) were completed and manuscripts submitted. Venipuncture blood samples were collected from another 756 breast cancer cases identified on the third survey, and a pilot study of DNA fingerprick blood sample collection by mail was launched. Additionally, we completed development of the Version-3.5 dosimetry system. Corroboration of 152 lifetime dose estimates using individual FISH measurements gives us confidence to use the Version 3.5 dose estimates to conduct dose-response analyses and proceed with publication.Cancer Mortality in Russian Nuclear Workers Exposed to Plutonium and Protracted External RadiationA cohort of 26,000 Mayak nuclear facility workers (in the Russian Federation) is being studied because they comprise a unique occupational group for protracted exposure to external radiation at high doses and exposure to plutonium. Dose-response relationships for exposure to external radiation were demonstrated for mortality from leukemia; cancers of the lung, liver and bone (analyzed as a single category); and all solid cancers other than lung, bone and liver cancer. Patterns of risk by sex, age at exposure and time since exposure were generally similar to those observed in A-bomb survivors. Mortality analyses have also clearly demonstrated that internal exposure to plutonium results in excess risks for cancers of the lung, liver and bone cancers, the sites receiving the highest doses from plutonium. Recently conducted dose-response analyses of lung cancer mortality indicated significant associations for both internal dose to the lung from plutonium and external dose (p greater than 0.001).