Addressing the Challenge of Successful One-Stage Lumpectomy for DCIS.

BackgroundBreast conserving surgery represents the preferred surgical treatment option for patients with early-stage breast cancer. Reexcision rates are generally higher for patients undergoing lumpectomies for ductal carcinoma in situ (DCIS) compared to invasive breast cancer, as the microscopic extent of disease is difficult to assess during excision. This study investigated the clinicopathological characteristics of patients undergoing BCS for pure DCIS and reexcision rates over time, including the effect of the MarginProbe™ device.MethodsWe queried our prospectively maintained Institutional Breast Cancer Database for patients diagnosed with DCIS and treated with BCS as their primary procedure from 2010-2021. The primary endpoint was the rate of reexcision. Variables of interest included age at diagnosis, race/ethnicity, mode of diagnostic imaging, mammographic breast density, method of core biopsy, nuclear grade, size of DCIS, multifocality, DCIS subtype, and MarginProbe™ use.ResultsPapillary DCIS (P < 0.004) and larger size (P < 0.001) was associated with an increased reexcision rate. There were also differences in the method of core biopsy (P < 0.001), with stereotactic core biopsy predominating among patients who did not require reexcision (71.3% vs 49.5%). In an unadjusted estimate for the odds ratio for association, patients who had MarginProbe™ used were 81% less likely to require reexcision (OR = 0.19, 95% CI = 0.12, 0.31, P < 0.0001).ConclusionYounger age, papillary DCIS, larger DCIS size, and non-stereotactic core biopsy method were found to be associated with higher reexcision rates. Additionally, patients whose primary procedures included intraoperative margin assessment with the MarginProbe™ were significantly less likely to require reexcision.