Claire Edwards1, Feng Gao2, Gary M Freedman3, Julie A Margenthaler4, Carla Fisher5. 1. Department of Surgery, George Washington University Medical Center, Washington, District of Columbia. Electronic address: cedwards@mfa.gwu.edu. 2. Division of Biostatistics, Washington University School of Medicine, St. Louis, Missouri. 3. Division of Radiation Oncology, Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania. 4. Department of Surgery, Washington University School of Medicine, St. Louis, Missouri. 5. Division of Surgical Oncology, Rena Rowan Breast Center, Abramson Cancer Center, Perelman School of Medicine, University of Pennsylvania, Philadelphia, Pennsylvania.
Abstract
BACKGROUND: In breast conservation surgery (BCS) for breast cancer, the appropriate surgical margin is controversial. Margin index, a mathematical relationship between tumor size and closest margin, has been shown to be predictive of the probability of residual cancer after BCS for early stage breast cancer. We applied this tool to the same population of patients at our institution to evaluate its ability to predict residual disease after BCS. METHODS: We retrospectively reviewed a prospectively maintained database of women undergoing BCS between 1980 and 2010 at the University of Pennsylvania. A total of 246 women underwent re-excision because of close margins. Average margin index between groups with and without residual disease in the re-excision specimen was compared using the Student t-test. A receiver operating curve was created using logistic regression to assess the overall diagnostic ability of the margin index on the presence or absence of residual disease. RESULTS: Of patients who underwent re-excision, 29% of patients had residual disease. We analyzed several cutoff values for margin index, but none proved to be significant predictors of residual disease. Average margin index was significantly higher for patients without residual disease compared with patients with residual invasive cancer but not for patients with residual ductal carcinoma in situ. CONCLUSIONS: In women undergoing BCS for early stage breast cancer at our institution, margin index was not predictive of the presence of residual cancer on re-excision. We hypothesize that the predictive ability of a margin index is likely limited by several factors including the presence of ductal carcinoma in situ and the location and extent of the close margin.
BACKGROUND: In breast conservation surgery (BCS) for breast cancer, the appropriate surgical margin is controversial. Margin index, a mathematical relationship between tumor size and closest margin, has been shown to be predictive of the probability of residual cancer after BCS for early stage breast cancer. We applied this tool to the same population of patients at our institution to evaluate its ability to predict residual disease after BCS. METHODS: We retrospectively reviewed a prospectively maintained database of women undergoing BCS between 1980 and 2010 at the University of Pennsylvania. A total of 246 women underwent re-excision because of close margins. Average margin index between groups with and without residual disease in the re-excision specimen was compared using the Student t-test. A receiver operating curve was created using logistic regression to assess the overall diagnostic ability of the margin index on the presence or absence of residual disease. RESULTS: Of patients who underwent re-excision, 29% of patients had residual disease. We analyzed several cutoff values for margin index, but none proved to be significant predictors of residual disease. Average margin index was significantly higher for patients without residual disease compared with patients with residual invasive cancer but not for patients with residual ductal carcinoma in situ. CONCLUSIONS: In women undergoing BCS for early stage breast cancer at our institution, margin index was not predictive of the presence of residual cancer on re-excision. We hypothesize that the predictive ability of a margin index is likely limited by several factors including the presence of ductal carcinoma in situ and the location and extent of the close margin.
Authors: J A van Dongen; A C Voogd; I S Fentiman; C Legrand; R J Sylvester; D Tong; E van der Schueren; P A Helle; K van Zijl; H Bartelink Journal: J Natl Cancer Inst Date: 2000-07-19 Impact factor: 13.506
Authors: Laurence E McCahill; Richard M Single; Erin J Aiello Bowles; Heather S Feigelson; Ted A James; Tom Barney; Jessica M Engel; Adedayo A Onitilo Journal: JAMA Date: 2012-02-01 Impact factor: 56.272
Authors: J A Jacobson; D N Danforth; K H Cowan; T d'Angelo; S M Steinberg; L Pierce; M E Lippman; A S Lichter; E Glatstein; P Okunieff Journal: N Engl J Med Date: 1995-04-06 Impact factor: 91.245