Radiation Epidemiology Branch, National Cancer Institute, Rockville, Maryland 20852-7238, USA.
Int J Radiat Oncol Biol Phys. 2013 Feb 1;85(2):451-9. doi: 10.1016/j.ijrobp.2012.04.029. Epub 2012 Jun 9.
To assess the shape of the dose response for various cancer endpoints and modifiers by age and time.
Reanalysis of the US peptic ulcer data testing for heterogeneity of radiogenic risk by cancer endpoint (stomach, pancreas, lung, leukemia, all other).
There are statistically significant (P<.05) excess risks for all cancer and for lung cancer and borderline statistically significant risks for stomach cancer (P=.07), and leukemia (P=.06), with excess relative risks Gy(-1) of 0.024 (95% confidence interval [CI] 0.011, 0.039), 0.559 (95% CI 0.221, 1.021), 0.042 (95% CI -0.002, 0.119), and 1.087 (95% CI -0.018, 4.925), respectively. There is statistically significant (P=.007) excess risk of pancreatic cancer when adjusted for dose-response curvature. General downward curvature is apparent in the dose response, statistically significant (P<.05) for all cancers, pancreatic cancer, and all other cancers (ie, other than stomach, pancreas, lung, leukemia). There are indications of reduction in relative risk with increasing age at exposure (for all cancers, pancreatic cancer), but no evidence for quadratic variations in relative risk with age at exposure. If a linear-exponential dose response is used, there is no significant heterogeneity in the dose response among the 5 endpoints considered or in the speed of variation of relative risk with age at exposure. The risks are generally consistent with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers.
There are excess risks for various malignancies in this data set. Generally there is a marked downward curvature in the dose response and significant reduction in relative risk with increasing age at exposure. The consistency of risks with those observed in the Japanese atomic bomb survivors and in groups of nuclear workers implies that there may be little sparing effect of fractionation of dose or low-dose-rate exposure.
通过年龄和时间评估各种癌症终点和修饰剂的剂量反应形状。
重新分析美国消化性溃疡数据，通过癌症终点（胃、胰腺、肺、白血病、所有其他）测试放射性风险的异质性。
所有癌症、肺癌和胃癌（P=.07）以及白血病（P=.06）的超额风险具有统计学意义（P<.05），Gy(-1)的超额相对风险分别为 0.024（95%置信区间 [CI] 0.011, 0.039）、0.559（95% CI 0.221, 1.021）、0.042（95% CI -0.002, 0.119）和 1.087（95% CI -0.018, 4.925）。当调整剂量反应曲率时，胰腺癌的超额风险具有统计学意义（P=.007）。在剂量反应中明显呈现出总体向下的曲率，所有癌症、胰腺癌和所有其他癌症（即除胃、胰腺、肺、白血病外的其他癌症）均具有统计学意义（P<.05）。有迹象表明，随着暴露年龄的增加，相对风险降低（所有癌症、胰腺癌），但没有证据表明暴露年龄的相对风险随二次方变化。如果使用线性指数剂量反应，那么在考虑的 5 个终点之间或相对风险随暴露年龄的变化速度方面，剂量反应没有显著的异质性。这些风险通常与日本原子弹幸存者和核工作人员群体中观察到的风险一致。
在这个数据集中有各种恶性肿瘤的超额风险。通常，剂量反应呈明显的向下曲率，随着暴露年龄的增加，相对风险显著降低。与日本原子弹幸存者和核工作人员群体中观察到的风险的一致性表明，剂量分割或低剂量率暴露可能没有明显的保护作用。
