RESUMEN
BACKGROUND: There is lack of consensus regarding re-excision in breast-conserving therapy (BCT) and close margins. We hypothesize that margin width does not predict residual disease. METHODS: The cancer registry was queried from 2003 to 2008 for patients with BCT who underwent re-excision for <2-mm margins. Factors associated with additional disease were evaluated. RESULTS: One thousand eight hundred forty-three patients underwent BCT. Our re-excision rate was 42%. Clinicopathologic factors from 228 patients were analyzed. One hundred five patients (46%) had additional disease; of those, 58% had BCT and 42% mastectomy. One hundred twenty-three (54%) had no additional disease; of those 82% had BCT and 18% mastectomy. Of the 66 patients who underwent mastectomy, 44 (67%) had residual disease; of the 161 who had BCT, 61 (38%) had residual disease (P < 0.01). On univariate analysis, margin width did not correlate with residual disease. Multifocality, non-invasive histology, increasing number of close margins, and higher grade predicted additional disease (P < 0.05). On multivariate analysis, only number of close margins remained significant. CONCLUSIONS: Margin width does not predict additional disease. This challenges the practice of using this to select re-excision candidates. Our data suggest that tumor behavior and extent of disease, defined by volume of residual disease and invasiveness of histology, play a more significant role.