Relationship Between Margin Width and Recurrence of Ductal Carcinoma In Situ

Abstract

Structured abstract Objective Our goal was to investigate, in a large population of women with DCIS and long follow-up, the relationship between margin width and recurrence, controlling for other characteristics. Summary Background Data While DCIS has minimal mortality, recurrence rates after breast-conserving surgery (BCS) are significant, and half are invasive. Positive margins are associated with increased risk of local recurrence, but there is no consensus regarding optimal negative margin width. Methods We retrospectively reviewed a prospective database of DCIS patients undergoing BCS from 1978–2010. Univariate and Cox proportional hazard models were used to investigate the association between margin width and recurrence. Results 2996 cases were identified, of which 363 recurred. Median follow-up for women without recurrence was 75mo (range 0–30years); 732 were followed for ≥10yrs. Controlling for age, family history, presentation, nuclear grade, number of excisions, radiotherapy (RT), endocrine therapy, and year of surgery, margin width was significantly associated with recurrence in the entire population. Larger negative margins were associated with a lower hazard ratio compared to positive margins. An interaction between RT and margin width was significant (p<0.03); the association of recurrence with margin width was significant in those without RT (p<0.0001), but not in those with RT (p=0.95). Conclusions In women not receiving RT, wider margins are significantly associated with a lower rate of LR. Obtaining wider negative margins may be important in reducing the risk of recurrence in women who choose not to undergo RT, and may not be necessary in those that receive RT.

Do LORIS Trial Eligibility Criteria Identify a Ductal Carcinoma In Situ Patient Population at Low Risk of Upgrade to Invasive Carcinoma?

“…We have previously reported adjuvant therapy use among larger cohorts of patients with DCIS treated at our institution, with utilization of radiation therapy in recent years for women with DCIS following BCS at approximately 60%, and the use of endocrine therapy substantially lower, at approximately 23%, with no patients receiving chemotherapy. 15-17 Similar utilization of adjuvant therapy for patients with DCIS has been reported from national database reviews. According to National Cancer Institute Surveillance Epidemiology and End Results (SEER) data, approximately 35%–40% of women managed with BCS for DCIS in 2005 did not receive adjuvant radiation therapy 18 , and in a review of over 206,000 women with DCIS reported to the National Cancer Database between 2005 and 2012, the minority of women (37%) received adjuvant endocrine therapy.…”

The Association of Surgical Margins and Local Recurrence in Women with Ductal Carcinoma In Situ Treated with Breast-Conserving Therapy: A Meta-Analysis

“…Due to heterogeneity in margin definitions across studies, positive margins were re-categorized as either 0mm (ink on tumour, nine studies 19-27 ) or <1mm (seven studies 28-34 ). In addition, margins of <2mm (three studies 18;35;36 ) or <3mm (one study 37 ) were considered positive when 0mm or <1mm were not reported.…”

“…One margin distance could be included for each study. When multiple distances were available, the largest was chosen (with the exception of the only study to apply a 5mm distance 19 , and a large study defining “close” margins as <2mm 27 ). The effect of alternative distance categorisations for potentially influential studies was investigated.…”

Society of Surgical Oncology–American Society for Radiation Oncology–American Society of Clinical Oncology Consensus Guideline on Margins for Breast-Conserving Surgery With Whole-Breast Irradiation in Ductal Carcinoma in Situ

“…After adjustment for multiple factors, margin width was a more highly significant predictor of IBTR (p < 0.0001). 22 The MP felt that, overall, the heterogeneity of the evidence between the above-reported studies did not allow for a definitive recommendation for margin widths greater than 2 mm in patients foregoing RT.…”

“…The conclusion that re-excision could be selectively employed with margins smaller than 2 mm was influenced by the high long-term rates of local control reported in the NSABP DCIS trials which required a margin of no ink on tumor 7 as well as the study of Van Zee et al which, after adjusting for multiple covariates, found no difference in risk between margins of ≤ 2 mm and more widely clear margins in patients receiving WBRT. 22 …”