Does Gross Margin Examination Reduce Re-excision Rate in Breast Conservation for Invasive Carcinoma? CALLER Review

Determine if Gross Margin Examination reduces margin re-excision rate. Our institutional practice is to perform Gross Margin Examination (GME) with Real-time re-excision (RRE) for all breast conservation specimens with Invasive Carcinoma.

Chart review was done to determine if this practice is helpful. 51 CALLER charts were reviewed from December 2016 to December 2017.

Thirty-three underwent margin RRE based on the GME. 11 had cancer in the re-resected margin, 6 of which were cleared with the RRE. The other 5 were reoperated on to clear the margin because on final pathology a margin other than the re-resected margin was positive for malignancy. GME was helpful in preventing reoperation in 55%. None of the remaining 22 patients receiving were found to have a positive margin on final pathology, with 1.6 margins on average re-resected. 13/18 patients did not have RRE and had a final clear margin, but of the other 5, final margin was positive for DCIS in 2 and Invasive Cancer in 3. GME missed invasive disease at the margin in 3 of these 18 patients.

GME was helpful in preventing reoperation in 6 of 11 patients who would have had a positive margin. However, this resulted in the unnecessary removal of additional normal breast tissue in 22 patients. 3 patients' positive margins were missed with GME and required reoperation. 13 patients were able to avoid re-excision and 11 were able to clear their margin in real-time, improving outcomes 24/51 patients. GME therefore does appear useful.