Alison Laws1, Mantaj S Brar2, Antoine Bouchard-Fortier1, Brad Leong3, May Lynn Quan1. 1. Department of Surgery, Foothills Medical Centre, University of Calgary, Canada. 2. Department of Surgery, Zane Cohen Centre for Digestive Diseases, Mount Sinai Hospital, University of Toronto, Canada. 3. Cancer Surgery Alberta, Alberta Health Services, Canada.
Abstract
BACKGROUND AND OBJECTIVES: Using a 2 mm margin criteria, we evaluated the effect of intra-operative margin assessment on margin status and re-excisions following breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS). METHODS: We identified patients undergoing BCS for DCIS from a prospective, population-based database. Multivariable logistic regression was used to determine the effect of specimen mammography, ultrasound and macroscopic assessment by a pathologist on margins and re-excision rates. RESULTS: In 588 patients, 52% (95% confidence interval [CI], 48%-56%) had positive margins (<2 mm), 39% (95% CI, 35%-43%) had a re-excision and 15% (95% CI, 12%-18%) had completion mastectomy. There were few re-excisions for margins ≥2 mm (2%). Adjusting for confounders, any margin assessment versus wire localization alone did not reduce positive margins (odds ratio [OR], 0.75; P = 0.202) or re-excisions (OR, 1.14; P = 0.564), however both outcomes varied by type of technique ( P < 0.001). Individually, only macroscopic assessment by pathologist reduced positive margins (OR, 0.54; P = 0.002) and re-excisions (OR, 0.61; P = 0.036). CONCLUSIONS: Despite adherence to a 2 mm margin criteria, re-excision rates remain high following BCS for DCIS, with 39% converted to mastectomy when re-excision is required. Intra-operative margin assessment does not appear to reduce re-excisions; in particular, surgeons should be aware of the limitations of specimen mammography for margin assessment in DCIS.
BACKGROUND AND OBJECTIVES: Using a 2 mm margin criteria, we evaluated the effect of intra-operative margin assessment on margin status and re-excisions following breast-conserving surgery (BCS) for ductal carcinoma in situ (DCIS). METHODS: We identified patients undergoing BCS for DCIS from a prospective, population-based database. Multivariable logistic regression was used to determine the effect of specimen mammography, ultrasound and macroscopic assessment by a pathologist on margins and re-excision rates. RESULTS: In 588 patients, 52% (95% confidence interval [CI], 48%-56%) had positive margins (<2 mm), 39% (95% CI, 35%-43%) had a re-excision and 15% (95% CI, 12%-18%) had completion mastectomy. There were few re-excisions for margins ≥2 mm (2%). Adjusting for confounders, any margin assessment versus wire localization alone did not reduce positive margins (odds ratio [OR], 0.75; P = 0.202) or re-excisions (OR, 1.14; P = 0.564), however both outcomes varied by type of technique ( P < 0.001). Individually, only macroscopic assessment by pathologist reduced positive margins (OR, 0.54; P = 0.002) and re-excisions (OR, 0.61; P = 0.036). CONCLUSIONS: Despite adherence to a 2 mm margin criteria, re-excision rates remain high following BCS for DCIS, with 39% converted to mastectomy when re-excision is required. Intra-operative margin assessment does not appear to reduce re-excisions; in particular, surgeons should be aware of the limitations of specimen mammography for margin assessment in DCIS.
Authors: Lisanne L de Boer; Esther Kho; Koen K Van de Vijver; Marie-Jeanne T F D Vranken Peeters; Frederieke van Duijnhoven; Benno H W Hendriks; Henricus J C M Sterenborg; Theo J M Ruers Journal: Breast Cancer Res Date: 2021-05-22 Impact factor: 6.466
Authors: Benedikt Schaefgen; Annika Funk; H-P Sinn; Thomas Bruckner; Christina Gomez; Aba Harcos; Anne Stieber; Annabelle Haller; Juliane Nees; Riku Togawa; André Pfob; André Hennigs; Johanna Hederer; Fabian Riedel; Sarah Fastner; Christof Sohn; Jörg Heil; Michael Golatta Journal: Breast Cancer Res Treat Date: 2021-12-08 Impact factor: 4.872