Background This prospective cohort study aimed to assess whether postoperative radiotherapy could safely be omitted in women ≥ 65 years with low-risk, estrogen receptor (ER)-positive T1N0 breast cancer treated with breast-conserving surgery and adjuvant endocrine therapy. Methods Eligible patients were women ≥ 65 years with unifocal, non-lobular, grade 1 or 2, ER-positive, pT1N0 breast cancer treated with breast-conserving surgery and endocrine therapy for five years. Patients were followed up with mammography at least annually for 10 years. The primary endpoint was local recurrence. Secondary endpoints were contralateral breast cancer, recurrence-free survival, and overall survival. Results The final study cohort included 601 patients with a median age of 71 years (range: 65 to 90 years) and a median tumor size of 11 mm (range: 3 to 20 mm). Median follow-up time was 119 months (interquartile range: 103 to 121 months). The cumulative incidence of local recurrence was 1.5% (95% confidence interval (CI): 0.8 to 2.8%) and 5.5% (95% CI: 3.8 to 7.6%) at 5 and 10 years, respectively. The cumulative incidence of contralateral breast cancer was 1.7% (95% CI: 0.9 to 3.0%) at 5 years and 4.5% (95% CI: 3.0 to 6.6%) at 10 years. The overall survival rate at 10 years was 83.1% (95% CI: 80.8 to 85.4%). In total, three patients (0.5%) died due to breast cancer. Conclusion Our results support the possibility to omit radiotherapy after breast-conserving surgery in a well-defined subgroup of women aged ≥ 65 years with low-risk, ER-positive, pT1N0 breast cancer receiving adjuvant endocrine therapy.

中文翻译：

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低风险乳腺癌保乳手术后漏诊


背景 这项前瞻性队列研究旨在评估接受保乳手术和辅助内分泌治疗的 65 ≥低风险、雌激素受体 （ER） 阳性 T1N0 乳腺癌女性是否可以安全地省略术后放疗。方法 符合条件的患者是 65 ≥女性，患有单灶性、非小叶性、1 级或 2 级、ER 阳性、pT1N0 乳腺癌，接受保乳手术和内分泌治疗 5 年。患者至少每年接受一次乳腺 X 线摄影随访，持续 10 年。主要终点是局部复发。次要终点是对侧乳腺癌、无复发生存期和总生存期。结果 最终研究队列包括 601 例患者，中位年龄为 71 岁 （范围： 65 至 90 岁），中位肿瘤大小为 11 毫米 （范围： 3 至 20 毫米）。中位随访时间为 119 个月 （四分位距： 103 至 121 个月）。5 年和 10 年局部复发的累积发生率分别为 1.5% （95% 置信区间 （CI）： 0.8 至 2.8%） 和 5.5% （95% CI： 3.8 至 7.6%）。对侧乳腺癌的累积发病率在 5 年时为 1.7% （95% CI： 0.9 至 3.0%），在 10 年时为 4.5% （95% CI： 3.0 至 6.6%）。10 年总生存率为 83.1% （95% CI： 80.8 至 85.4%）。共有 3 名患者 （0.5%） 死于乳腺癌。结论 我们的结果支持在接受辅助内分泌治疗的 65 岁低风险、ER 阳性 pT1N0 乳腺癌女性亚组中≥保乳手术后省略放疗的可能性。