Clinicopathological Predictors of Positive Resection Margins in Breast-Conserving Surgery

• Published in: Annals of surgical oncology Vol. 31; no. 6; pp. 3939 - 3947
• Main Authors: Chauhan, Hemali, Jiwa, Natasha, Nagarajan, Vikneswaran Raj, Thiruchelvam, Paul, Hogben, Katy, Al-Mufti, Ragheed, Hadjiminas, Dimitri, Shousha, Sami, Cutress, Ramsey, Ashrafian, Hutan, Takats, Zoltan, Leff, Daniel Richard
• Format: Journal Article
• Language: English
• Published: Cham Springer International Publishing 01-06-2024; Springer Nature B.V
• Subjects: Adult; Aged; Aged, 80 and over; Breast; Breast Neoplasms - pathology; Breast Neoplasms - surgery; Breast Oncology; Breast surgery; Carcinoma, Ductal, Breast - pathology; Carcinoma, Ductal, Breast - surgery; Carcinoma, Intraductal, Noninfiltrating - pathology; Carcinoma, Intraductal, Noninfiltrating - surgery; Female; Follow-Up Studies; Humans; Lumpectomy; Margins of Excision; Mastectomy, Segmental - methods; Medicine; Medicine & Public Health; Middle Aged; Oncology; Prognosis; Retrospective Studies; Surgery; Surgical Oncology; Positive margin predictors; Breast-conserving surgery
• ISSN: 1068-9265; 1534-4681
• DOI: 10.1245/s10434-024-15153-8

Background
Ductal carcinoma in situ (DCIS) is associated with risk of positive resection margins following breast-conserving surgery (BCS) and subsequent reoperation. Prior reports grossly underestimate the risk of margin positivity with IBC containing a DCIS component (IBC + DCIS) due to patient-level rather than margin-level analysis.
Objective
The aim of this study was to delineate the relative risk of IBC + DCIS compared with pure IBC (without a DCIS component) on margin positivity through detailed margin-level interrogation.
Methods
A single institution, retrospective, observational cohort study was conducted in which pathology databases were evaluated to identify patients who underwent BCS over 5 years (2014–2019). Margin-level interrogation included granular detail into the extent, pathological subtype and grade of disease at each resection margin. Predictors of a positive margin were computed using multivariate regression analysis.
Results
Clinicopathological details were examined from 5454 margins from 909 women. The relative risk of a positive margin with IBC + DCIS versus pure IBC was 8.76 (95% confidence interval [CI] 6.64–11.56) applying UK Association of Breast Surgery guidelines, and 8.44 (95% CI 6.57–10.84) applying the Society of Surgical Oncology/American Society for Radiation Oncology guidelines. Independent predictors of margin positivity included younger patient age (0.033, 95% CI 0.006–0.060), lower specimen weight (0.045, 95% CI 0.020–0.069), multifocality (0.256, 95% CI 0.137–0.376), lymphovascular invasion (0.138, 95% CI 0.068–0.208) and comedonecrosis (0.113, 95% CI 0.040–0.185).
Conclusions
Compared with pure IBC, the relative risk of a positive margin with IBC + DCIS is approximately ninefold, significantly higher than prior estimates. This margin-level methodology is believed to represent the impact of DCIS more accurately on margin positivity in IBC.