Hall P, Holm L E, Lundell G, Bjelkengren G, Larsson L G, Lindberg S, Tennvall J, Wicklund H, Boice J D
Department of General Oncology, Radiumhemmet, Karolinska Hospital, Stockholm, Sweden.
Br J Cancer. 1991 Jul;64(1):159-63. doi: 10.1038/bjc.1991.261.
Cancer risks were studied in 834 thyroid cancer patients given 131I (4,551 MBq, average) and in 1,121 patients treated by other means in Sweden between 1950 and 1975. Record-linkage with the Swedish Cancer Register identified 99 new cancers more than 2 years after 131I therapy [standardised incidence ratio (SIR) = 1.43; 95% confidence interval (CI) 1.17-1.75] vs 122 (SIR = 1.19; 95% CI 0.88-1.42) in patients not receiving 131I. In females treated with 131I overall SIR was 1.45 (95% CI 1.14-1.83) and significantly elevated were noted for tumours of the salivary glands, genital organs, kidney and adrenal gland. No elevated risk of a subsequent breast cancer or leukaemia was noted. SIR did not change over time, arguing against a strong radiation effect of 131I. Organs that were estimated to have received more than 1.0 Gy had together a significantly increased risk of a subsequent cancer following 131I treatment (SIR = 2.59; n = 18). A significant trend was seen for increasing activities of 131I with highest risk for patients exposed to greater than or equal to 3,664 MBq (SIR = 1.80; 95% CI 1.20-2.58). No specific cancer or group of cancers could be convincingly linked to high-dose 131I exposures since SIR did not increase after 10 years of observation. However, upper confidence intervals could not exclude levels of risk that would be predicted based on data from the study of atomic bomb survivors. We conclude that the current practice of extrapolating the effects of high-dose exposures to lower-dose situations is unlikely to seriously underestimate radiation hazards for low LET radiation.
1950年至1975年间，在瑞典对834例接受131I治疗（平均剂量4551MBq）的甲状腺癌患者以及1121例接受其他治疗的患者的癌症风险进行了研究。与瑞典癌症登记处的记录关联显示，131I治疗后2年以上出现99例新发癌症[标准化发病率比（SIR）=1.43；95%置信区间（CI）1.17 - 1.75]，而未接受131I治疗的患者中有122例（SIR = 1.19；95% CI 0.88 - 1.42）。在接受131I治疗的女性中，总体SIR为1.45（95% CI 1.14 - 1.83），且唾液腺、生殖器官、肾脏和肾上腺肿瘤的发病率显著升高。未发现后续患乳腺癌或白血病的风险增加。SIR未随时间变化，这与131I的强烈辐射效应相悖。估计接受超过1.0Gy辐射的器官在131I治疗后发生后续癌症的风险显著增加（SIR = 2.59；n = 18）。观察到131I剂量增加存在显著趋势，暴露于大于或等于3664MBq的患者风险最高（SIR = 1.80；95% CI 1.20 - 2.58）。由于观察10年后SIR未增加，没有特定的癌症或癌症组能令人信服地与高剂量131I暴露相关联。然而，置信区间上限不能排除基于原子弹幸存者研究数据所预测的风险水平。我们得出结论，当前将高剂量暴露效应外推至低剂量情况的做法不太可能严重低估低LET辐射的辐射危害。
