Hsieh Wan-Hua, Lin I-Feng, Ho Jung-Chun, Chang Peter Wushou
Department of Public Health, Tzu Chi University, Hualien 970, Taiwan.
Institute of Public Health, School of Medicine, National Yang-Ming University, Taipei 112, Taiwan.
Br J Cancer. 2017 Dec 5;117(12):1883-1887. doi: 10.1038/bjc.2017.350. Epub 2017 Oct 3.
The current study followed-up site-specific cancer risks in an unique cohort with 30 years' follow-up after long-term low-dose-rate radiation exposure in Taiwan.
Six thousand two hundred and forty two Taiwanese people received extra exposure in residential and school buildings constructed with Co-60-contaminated steel from 1982 until informed and relocated in early 1990s. The additional doses received have been estimated. During 1983-2012, 300 cancer cases were identified through the national cancer registry in Taiwan, 247 cases with minimum latent periods from initial exposure. The hazard ratios (HR) of site-specific cancers were estimated with additional cumulative exposure estimated individually.
Dose-dependent risks were statistically significantly increased for leukaemia excluding chronic lymphocytic leukaemia (HR 1.18; 90% CI 1.04-1.28), breast cancers (HR 1.11; 90% CI 1.05-1.20), and all cancers (HR 1.05; 90% CI 1.0-1.08, P=0.04). Women with an initial age of exposure lower than 20 were shown with dose response increase in breast cancers risks (HR 1.38; 90% CI 1.14-1.60; P=0.0008).
Radiation exposure before age 20 was associated with a significantly increased risk of breast cancer at much lower radiation exposure than observed previously.
本研究对台湾一个独特队列进行了随访，该队列在长期低剂量率辐射暴露后进行了30年的随访，以了解特定部位癌症风险。
1982年至20世纪90年代初被告知并搬迁之前，6242名台湾人在使用受钴-60污染钢材建造的住宅和学校建筑中受到额外辐射。已估算出他们额外接受的剂量。在1983年至2012年期间，通过台湾国家癌症登记处确定了300例癌症病例，其中247例有从初次暴露开始的最短潜伏期。根据个体估算的额外累积暴露量，估算特定部位癌症的风险比（HR）。
除慢性淋巴细胞白血病外的白血病（HR 1.18；90%CI 1.04 - 1.28）、乳腺癌（HR 1.11；90%CI 1.05 - 1.20）和所有癌症（HR 1.05；90%CI 1.0 - 1.08，P = 0.04）的剂量依赖性风险在统计学上显著增加。初次暴露年龄低于20岁的女性乳腺癌风险呈剂量反应增加（HR 1.38；90%CI 1.14 - 1.60；P = 0.0008）。
20岁之前的辐射暴露与乳腺癌风险显著增加相关，且辐射暴露水平远低于先前观察到的水平。
