The safety of multiple re-excisions after lumpectomy for breast cancer.

BACKGROUND: Breast cancer patients may undergo multiple re-excisions after lumpectomy in an attempt to obtain clear margins and avoid mastectomy. We sought to determine the overall local recurrence rate and surgical outcome of patients undergoing two or more re-excisions and to identify predictors of success in attaining clear margins.
METHODS: Retrospective review of breast cancer patients who underwent lumpectomy for invasive cancer or ductal carcinoma in situ (DCIS) from 1997 to 2007. Patients who underwent two or more re-excisions were identified and analyzed.
RESULTS: We identified 3,737 patients who underwent lumpectomy over this 10-year period. 875 (23.4%) had close or positive margins requiring a second procedure; 797 (91.1%) had a re-excision; and 78 (8.9%) went directly to mastectomy. Seventy patients underwent multiple re-excisions; 66 patients had 2 re-excisions, 3 patients had 3 re-excisions, and 1 patient had 4 re-excisions. 70% (49/70) of multiple re-excision patients achieved clear margins (26 DCIS, 35 T1, 8 T2, and 1 T3 tumors). All 49 patients who successfully treated with multiple re-excisions received radiation. At a median follow-up of 64 months, 1 of 49 (2.0%) patients had an in-breast recurrence, and 1 of 49 (2.0%) patients had a distant recurrence. Statistically significant risk factors for persistently involved margins after two re-excisions included multifocality and positive lymph node status.
CONCLUSION: Multiple re-excisions to obtain clear margins are a safe alternative to mastectomy for women with invasive cancer or DCIS. There is an acceptably low risk of local and systemic failure when negative margins are ultimately achieved.