Review of third and fourth re-excision for narrow or positive margins of invasive and intraductal carcinoma.

The trend in breast surgery has shifted toward breast conservation. We reviewed our third and fourth breast re-excision cases, with an analysis of various factors used in making this decision. A retrospective analysis identified 585 patients who underwent re-excision surgery for positive or close margins of invasive carcinoma or ductal carcinoma in situ (DCIS). Of these patients 75 (13%) and 17 (3%) underwent third and fourth re-excisions, respectively. The indication for a third re-excision was the presence of positive and/or close (< or = 1 mm) margins for invasive carcinoma or DCIS in 72/75 patients. A third re-excision was done 31 days (range 8-123 days) after the second re-excision. Re-excision of margins was done in 45 (60%) patients, whereas 30 (40%) patients underwent mastectomy. Residual tumor mandated a fourth re-excision in 17 patients, which was done 45 days (range 14-87 days) after the third surgery. Re-excision of margins was done in 6 patients, whereas 11 patients underwent mastectomy. Involved or close margins with DCIS were the most common indication for re-excision, accounting for 61/75 (82%) of third and 16/17 (94%) of fourth re-excisions. Histopathology revealed that 28/75 (37%) of third and 7/17 (41%) of fourth re-excision patients had no residual tumor. In conclusion, the majority of re-excisions was done for margins < 1 mm. Lower rates of re-excision were noted in well-differentiated invasive carcinomas. A close or involved DCIS margin was more likely to lead to a third and even a fourth re-excision. The absence of residual tumors in 40% of patients undergoing third and fourth re-excisions calls for a review of margin guidelines for breast re-excision.