Hankey B F, Curtis R E, Naughton M D, Boice J D, Flannery J T
J Natl Cancer Inst. 1983 May;70(5):797-804.
Second breast cancer experience was examined for 27,175 primary breast cancer patients diagnosed in the State of Connecticut during 1935-75 with follow-up for second breast cancers through 1980. The overall ratio of observed to expected second breast cancers was 3.2. Relative risk was found to be inversely related to age at diagnosis and directly related to stage of the first breast cancer. The overall risk of second breast cancers was 711 per 100,000 person-years at risk. Risk of second breast cancers showed a similar relationship to age and stage as relative risk and was also directly related to calendar period of diagnosis of the first breast cancer. Some interactions were observed because patients less than 45 years old at diagnosis with positive nodes had elevated risks and relative risks in the early followup period, whereas less of an effect of stage on relative risk and risk was seen for older patients. The effect of the use of adjunctive radiation therapy on second breast cancer risk was also assessed by the ratio of the risk of second breast cancers for those patients who received both surgery and radiation to the risk of those patients who only received surgery being estimated for patients diagnosed during 1935-59 and for patients diagnosed during 1960-75. For both cohorts relative risks of 1.2-1.4 were found for the 5-year period immediately following diagnosis, likely resulting from the uncontrolled effect of stage in the analysis. Elevated long-term relative risks were not found for patients diagnosed during 1935-59. A long-term marginally statistically significant relative risk of 1.4 (greater than or equal to 10 yr after diagnosis) was found for patients diagnosed during 1960-75. The data do not indicate an overall pattern of relative risks consistent with an effect on long-term second breast cancer risk of radiation exposure to the opposite breast incurred during adjunctive radiation therapy for a first breast cancer.
对1935年至1975年间在康涅狄格州诊断出的27175例原发性乳腺癌患者的二次乳腺癌经历进行了研究，并对二次乳腺癌进行随访直至1980年。观察到的二次乳腺癌与预期二次乳腺癌的总体比例为3.2。发现相对风险与诊断时的年龄呈负相关，与首次乳腺癌的分期呈正相关。二次乳腺癌的总体风险为每100000人年风险中有711例。二次乳腺癌的风险与相对风险一样，与年龄和分期呈现相似的关系，并且也与首次乳腺癌的诊断日历期呈正相关。观察到一些相互作用，因为诊断时年龄小于45岁且有阳性淋巴结的患者在早期随访期风险和相对风险升高，而对于老年患者，分期对相对风险和风险的影响较小。还通过接受手术和放疗的患者的二次乳腺癌风险与仅接受手术的患者的风险之比，评估了辅助放疗对二次乳腺癌风险的影响，该比例是针对1935年至1959年诊断的患者以及1960年至1975年诊断的患者进行估算的。对于这两个队列，在诊断后的5年期间发现相对风险为1.2至1.4，这可能是由于分析中分期的未控制效应所致。在1935年至1959年诊断的患者中未发现长期相对风险升高。在1960年至1975年诊断的患者中发现了长期相对风险为1.4（诊断后大于或等于10年），具有边缘统计学意义。数据并未表明相对风险的总体模式与首次乳腺癌辅助放疗期间对另一侧乳房的辐射暴露对长期二次乳腺癌风险的影响一致。
