Risk factors for the presence of residual disease in women after partial mastectomy for invasive breast cancer: A single institution experience

Abstract

Background: We hypothesize that in addition to specimen margin widths other clinical variables may help predict the presence of residual disease in the lumpectomy bed.

Methods: Patients with Stage I-III invasive breast cancer (BC) who underwent partial mastectomy (PM) and re-excision from July 2010-June 2015 were retrospectively reviewed. Bivariate analyses were conducted using two-sample t-tests for continuous variables and Fisher's Exact tests for categorical variables. A multivariate logistic regression was then performed on significant bivariate analyses variables.

Results: ne-hundred and eighty-four patients were included in our analysis; 47% had residual disease on re-excision, while 53% had no residual disease. Tumor and nodal stage, operation type, type of disease present at margin, and number of positive margins were significantly associated with residual disease. On multivariate logistic regression, DCIS alone at the margin (p = 0.02), operation type (PM with cavity margins) (p = 0.003), and number of positive margins (3 or more) (p < 0.001) remained predictive of residual disease at re-excision.

Conclusion: Based on a more comprehensive review of the initial pathology, there are additional factors that can help predict the likelihood of finding residual disease and help guide the surgeon in the decision for re-excision.

Keywords: Invasive breast cancer; Margins; Partial mastectomy (PM); Re-excision; Residual disease.