Influence of breast cancer margin assessment method on the rates of positive margins and residual carcinoma

Background: We hypothesized that the method of breast cancer margin assessment may be associated with different rates of positive margins and residual carcinoma. Methods: A total of 178 breast cancer specimens were divided into 2 groups (A and B) based on the margin assessment method used. Rates of positive margins, re-excision, and residual carcinoma at re-excision were compared and analyzed statistically. Results: At least I margin was positive in 64.7% in group A and in 65.2% in group B. At directed re-excision 54% in group A and 51% in group B had residual carcinoma. The lateral margin was positive in 44% in group A compared with 26% in group B (P = .06). The posterior margin was positive in 19% in group A and in 51% in group B (P = .001). Conclusions: Two different breast cancer specimen margin assessment methods had comparable rates of positive margins and residual carcinoma at re-excision. Different patterns of specific margin positivity suggest that the method of margin assessment may alter results. (c) 2006 Excerpta Medica Inc. All rights reserved.