Department of Radiation Oncology, Toronto, ON, Canada.
ICES, Toronto, ON, Canada.
Breast Cancer Res Treat. 2019 Nov;178(1):169-176. doi: 10.1007/s10549-019-05364-z. Epub 2019 Jul 19.
The impact of Ductal Carcinoma in Situ (DCIS) with multiple foci of microinvasion (MI) (≤ 1 mm) on the risks of local recurrence (LR) and invasive LR is unknown, leading to uncertainty if DCIS with multiple foci of MI requires more aggressive treatment. We report a population-based analysis of the impact of multiple foci of MI, confirmed by pathology review, on the 15-year risks of LR and invasive LR treated with breast-conserving surgery (BCS) ± radiotherapy (RT).
Cohort includes all women diagnosed with DCIS ± MI from 1994 to 2003 treated with BCS ± RT. Cox proportional hazards model was used to evaluate the impact of multiple foci of MI on the risks of LR and invasive LR, adjusting for covariates. The 15-year local and invasive local recurrence-free survival rates were calculated using the Kaplan-Meier method with differences compared by log-rank test.
The cohort includes 2988 women treated by BCS; 2721 had pure DCIS (51% received RT), 267 had DCIS with one or more foci of MI (58% had RT). Median follow-up was 13 years. Median age at diagnosis was 58 years. On multivariable analyses, the presence of multiple foci of MI was associated with an increased risk of invasive LR (HR = 1.59, 95% CI 1.01-2.49, p = 0.04) but not DCIS LR (HR = 0.89, 95% CI 0.46, 1.76, p = 0.7). The 15-year invasive LRFS risks for cases with pure DCIS, with 1 focus or multiple foci of MI were 85.7%, 85.6%, 74.7% following treatment by BCS alone, 87.2%, 89.9%, and 77% for those treated with BCS + RT without boost and 89.2%, 91.3%, and 95% for women treated with BCS + RT and boost.
The presence of multiple foci of MI in DCIS is associated with higher 15-year risks of invasive LR after breast-conserving therapy compared to women with pure DCIS but treatment with whole breast and boost RT can mitigate this risk.
导管原位癌（DCIS）伴微浸润灶（MI）多发（≤1mm）对局部复发（LR）和浸润性 LR 风险的影响尚不清楚，因此对于 MI 多发的 DCIS 是否需要更积极的治疗存在不确定性。我们报告了一项基于人群的分析，研究了经病理证实的 MI 多发对保乳手术（BCS）±放疗（RT）治疗后 15 年 LR 和浸润性 LR 风险的影响。
该队列纳入了 1994 年至 2003 年间诊断为 DCIS±MI 并接受 BCS±RT 治疗的所有女性。采用 Cox 比例风险模型评估 MI 多发对 LR 和浸润性 LR 风险的影响，并进行了协变量调整。采用 Kaplan-Meier 法计算 15 年局部和局部浸润无复发生存率，并采用对数秩检验比较差异。
该队列包括 2988 例接受 BCS 治疗的女性；2721 例为单纯 DCIS（51%接受 RT），267 例为 DCIS 伴一个或多个 MI 灶（58%接受 RT）。中位随访时间为 13 年。中位诊断年龄为 58 岁。多变量分析显示，MI 多发与浸润性 LR 风险增加相关（HR=1.59，95%CI 1.01-2.49，p=0.04），但与 DCIS LR 无关（HR=0.89，95%CI 0.46-1.76，p=0.7）。单纯 BCS 治疗后，单纯 DCIS、1 个 MI 灶或多个 MI 灶的 15 年浸润性 LRFS 风险分别为 85.7%、85.6%、74.7%；未行局部加量 RT 的 BCS+RT 治疗组分别为 87.2%、89.9%和 77%；行局部加量 RT 的 BCS+RT 治疗组分别为 89.2%、91.3%和 95%。
与单纯 DCIS 相比，DCIS 伴 MI 多发与保乳治疗后 15 年浸润性 LR 风险增加相关，但全乳和加量 RT 治疗可降低这种风险。
