Perelman School of Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Department of Biostatistics and Epidemiology, University of Pennsylvania, Philadelphia, PA, USA.
Breast Cancer Res Treat. 2018 Jul;170(1):45-53. doi: 10.1007/s10549-018-4729-7. Epub 2018 Feb 27.
Women with ductal carcinoma in situ (DCIS) or early-stage breast cancer have an excellent prognosis, but their risk of developing second malignant neoplasms (SMNs) is not well established. We analyzed SMNs in a large cohort with long follow-up after breast conservation therapy.
The study population comprised 755 women with DCIS (n = 135) or stage I-II breast carcinoma (n = 620). Subjects were aged 25-89 (median 55) years when they underwent breast-conserving surgery followed by radiotherapy to the entire breast (60-68Gray) between 1992 and 2001. Additional treatment included hormonal therapy and/or chemotherapy based on clinical characteristics. SMNs were grouped by site. The rate of SMNs over time was determined using the Kaplan-Meier method. To compare the probability of developing SMNs overall and for specific organs or sites, probability estimates were obtained for a 55-year-old female from the Surveillance, Epidemiology, and End Results Program (SEER).
Median follow-up from radiotherapy was 13.8 years. The 15-year age-adjusted probability of developing any SMN was 12.0%, close to the SEER rate of 12.1% for a non-breast malignancy. Systemic therapy and higher-dose radiotherapy (> 63 Gray) were not associated with significantly increased risks of SMNs. Compared to SEER, significantly increased risk was noted for gynecologic cancers and melanoma.
Most SMNs were unrelated to treatment, and the 15-year incidence was similar to that of cancer in the SEER control group-findings that should be reassuring to patients. Further risk reduction is expected from prophylactic gynecologic surgery. Continued investigations into genetic links with melanoma are warranted.
患有导管原位癌（DCIS）或早期乳腺癌的女性预后极佳，但她们发生第二恶性肿瘤（SMN）的风险尚未得到充分证实。我们分析了在接受保乳治疗后进行长期随访的大型队列中的 SMN。
研究人群包括 755 名 DCIS（n=135）或 I 期- II 期乳腺癌患者（n=620）。这些患者在 1992 年至 2001 年间接受了保乳手术，随后接受了全乳放疗（60-68Gray），年龄为 25-89 岁（中位年龄 55 岁）。根据临床特征，还进行了激素治疗和/或化疗等辅助治疗。SMN 按部位分类。使用 Kaplan-Meier 法确定随时间推移的 SMN 发生率。为了比较总体和特定器官或部位发生 SMN 的概率，从监测、流行病学和最终结果计划（SEER）中获得了一名 55 岁女性的概率估计值。
放疗后中位随访时间为 13.8 年。15 年时年龄调整后的任何 SMN 发病概率为 12.0%，接近 SEER 非乳腺癌恶性肿瘤的 12.1%的发病概率。全身治疗和高剂量放疗（>63 Gray）与 SMN 的风险增加无显著相关性。与 SEER 相比，妇科癌症和黑色素瘤的风险显著增加。
大多数 SMN 与治疗无关，15 年的发病率与 SEER 对照组相似，这应使患者感到安心。预防性妇科手术有望进一步降低风险。需要进一步研究与黑色素瘤的遗传联系。
