Breast Service, Department of Surgery, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Department of Epidemiology and Biostatistics, Memorial Sloan Kettering Cancer Center, New York, NY, USA.
Ann Surg Oncol. 2017 Dec;24(13):3888-3895. doi: 10.1245/s10434-017-6043-8. Epub 2017 Aug 21.
Overdiagnosis and overtreatment of ductal carcinoma in situ (DCIS) are concerns, especially for women with low-volume, screen-detected DCIS. This study aimed to evaluate the outcomes for such patients.
Women who had minimal-volume DCIS (mDCIS, defined as DCIS diagnosed by core biopsy but with no residual disease on the surgical excision) treated with breast-conserving surgery from 1990 to 2011 were identified. Ipsilateral and contralateral breast events (IBE and CBE) were compared by competing-risk (CR) analysis. Kaplan-Meier (KM) estimates and log-rank tests were used to evaluate covariates.
The study identified 290 cases of mDCIS. The median age of the patients was 53 years. Radiation therapy (RT) was performed for 27.6% and endocrine therapy for 16.2% of the patients. The median follow-up period was 6.8 years. Overall, the IBE rates were 4.3% at 5 years and 12.3% at 10 years. Among the women not receiving RT, the 5- and 10-year IBE rates (5.4 and 14.5%) were higher than the CBE rates (1.8 and 2.7%). Among those receiving RT, the IBE rates (1.5 and 6.0%) were lower than the CBE rates (4.1 and 15.6%). The women receiving RT trended toward significantly lower IBE rates (p = 0.07). Age, grade, and endocrine therapy were not significantly associated with IBE risk.
Among the patients with mDCIS who did not receive RT, the IBE risk was substantially higher than the CBE risk, demonstrating that even DCIS of very low volume is associated with clinically relevant disease. The finding that the IBE risk was greater than the CBE risk supports current strategies that treat DCIS as a precursor rather than a risk marker. Women with mDCIS are not at negligible risk for IBE in the absence of adjuvant therapy.
导管原位癌（DCIS）的过度诊断和过度治疗是人们关注的问题，尤其是对于低体积、筛查发现的 DCIS 患者。本研究旨在评估此类患者的结局。
回顾性分析 1990 年至 2011 年间接受保乳手术治疗的、体积最小的 DCIS（mDCIS，通过核心活检诊断为 DCIS，但手术切除时无残留疾病）患者。采用竞争风险（CR）分析比较同侧和对侧乳腺事件（IBE 和 CBE）。Kaplan-Meier（KM）估计和对数秩检验用于评估协变量。
研究共纳入 290 例 mDCIS 患者，中位年龄为 53 岁。27.6%的患者接受了放射治疗（RT），16.2%的患者接受了内分泌治疗。中位随访时间为 6.8 年。总体而言，5 年和 10 年的 IBE 发生率分别为 4.3%和 12.3%。在未接受 RT 的女性中，5 年和 10 年的 IBE 发生率（5.4%和 14.5%）高于 CBE 发生率（1.8%和 2.7%）。在接受 RT 的女性中，IBE 发生率（1.5%和 6.0%）低于 CBE 发生率（4.1%和 15.6%）。接受 RT 的女性 IBE 发生率较低，但差异无统计学意义（p=0.07）。年龄、分级和内分泌治疗与 IBE 风险无显著相关性。
在未接受 RT 的 mDCIS 患者中，IBE 风险明显高于 CBE 风险，表明即使是体积非常小的 DCIS 也与具有临床意义的疾病相关。IBE 风险高于 CBE 风险的发现支持将 DCIS 视为一种前驱病变而不是风险标志物的现行策略。在没有辅助治疗的情况下，mDCIS 女性发生 IBE 的风险并非微不足道。
