Abstract：
BACKGROUND: Previous studies with the majority of breast cancer (BC) patients treated up to 2000 provided evidence that radiation dose to the heart from radiotherapy (RT) was linearly associated with increasing risk for long-term cardiac disease. RT techniques changed substantially over time. This study aimed to investigate the dose-dependent cardiac risk in German BC patients treated with more contemporary RT.
METHODS: In a cohort of 11,982 BC patients diagnosed in 1998-2008, we identified 494 women treated with 3D-conformal RT who subsequently developed a cardiac event. Within a nested case-control approach, these cases were matched to 988 controls. Controls were patients without a cardiac event after RT until the index date of the corresponding case. Separate multivariable conditional logistic regression models were used to assess the association of radiation to the complete heart and to the left anterior heart wall (LAHW) with cardiac events.
RESULTS: Mean dose to the heart for cases with left-sided BC was 4.27 Gy and 1.64 Gy for cases with right-sided BC. For controls, corresponding values were 4.31 Gy and 1.66 Gy, respectively. The odds ratio (OR) per 1 Gy increase in dose to the complete heart was 0.99 (95% confidence interval (CI): 0.94-1.05, P = .72). The OR per 1 Gy increase in LAHW dose was 1.00 (95% CI: 0.98-1.01, P = .68).
CONCLUSIONS: Contrary to previous studies, our study provided no evidence that radiation dose to the heart from 3D-conformal RT for BC patients treated between 1998 and 2008 was associated with risk of cardiac events.
METHODS: In a cohort of 11,982 BC patients diagnosed in 1998-2008, we identified 494 women treated with 3D-conformal RT who subsequently developed a cardiac event. Within a nested case-control approach, these cases were matched to 988 controls. Controls were patients without a cardiac event after RT until the index date of the corresponding case. Separate multivariable conditional logistic regression models were used to assess the association of radiation to the complete heart and to the left anterior heart wall (LAHW) with cardiac events.
RESULTS: Mean dose to the heart for cases with left-sided BC was 4.27 Gy and 1.64 Gy for cases with right-sided BC. For controls, corresponding values were 4.31 Gy and 1.66 Gy, respectively. The odds ratio (OR) per 1 Gy increase in dose to the complete heart was 0.99 (95% confidence interval (CI): 0.94-1.05, P = .72). The OR per 1 Gy increase in LAHW dose was 1.00 (95% CI: 0.98-1.01, P = .68).
CONCLUSIONS: Contrary to previous studies, our study provided no evidence that radiation dose to the heart from 3D-conformal RT for BC patients treated between 1998 and 2008 was associated with risk of cardiac events.
摘要：
背景：先前对2000年之前接受治疗的大多数乳腺癌（BC）患者的研究提供了证据，表明放疗（RT）对心脏的辐射剂量与长期心脏病风险的增加呈线性关系。RT技术随着时间的推移发生了很大变化。这项研究旨在调查接受更现代RT治疗的德国BC患者的剂量依赖性心脏风险。
方法：在1998-2008年诊断的11,982例BC患者的队列中，我们确定了494例接受3D适形RT治疗的女性，这些女性随后发生了心脏事件。在嵌套的案例控制方法中，这些病例与988例对照相匹配.对照组是在RT后直到相应病例的索引日期之前没有心脏事件的患者。使用单独的多变量条件逻辑回归模型来评估辐射对整个心脏和左前心壁（LAHW）与心脏事件的关联。
结果：左侧BC患者的心脏平均剂量为4.27Gy，右侧BC患者为1.64Gy。对于控件，相应值分别为4.31Gy和1.66Gy，分别。每增加1Gy剂量对整个心脏的比值比（OR）为0.99（95％置信区间（CI）：0.94-1.05，P=0.72）。LAHW剂量每增加1Gy的OR为1.00（95％CI：0.98-1.01，P=0.68）。
结论：与以前的研究相反，我们的研究没有证据表明,对于1998-2008年间接受治疗的BC患者,3D适形RT对心脏的辐射剂量与心脏事件风险相关.
方法：在1998-2008年诊断的11,982例BC患者的队列中，我们确定了494例接受3D适形RT治疗的女性，这些女性随后发生了心脏事件。在嵌套的案例控制方法中，这些病例与988例对照相匹配.对照组是在RT后直到相应病例的索引日期之前没有心脏事件的患者。使用单独的多变量条件逻辑回归模型来评估辐射对整个心脏和左前心壁（LAHW）与心脏事件的关联。
结果：左侧BC患者的心脏平均剂量为4.27Gy，右侧BC患者为1.64Gy。对于控件，相应值分别为4.31Gy和1.66Gy，分别。每增加1Gy剂量对整个心脏的比值比（OR）为0.99（95％置信区间（CI）：0.94-1.05，P=0.72）。LAHW剂量每增加1Gy的OR为1.00（95％CI：0.98-1.01，P=0.68）。
结论：与以前的研究相反，我们的研究没有证据表明,对于1998-2008年间接受治疗的BC患者,3D适形RT对心脏的辐射剂量与心脏事件风险相关.
