Evaluating the Effect of Margin Consensus Guideline Publication on Operative Patterns and Financial Impact of Breast Cancer Operation.

Background: This study sought to evaluate re-excision rates, patient satisfaction with their breasts, and healthcare costs before and after publication of 2014 Society of Surgical Oncology/American Society of Radiation Oncology consensus guideline on margins for breast conserving operation with whole-breast irradiation for stage I and II breast cancer at an academic institution.

Study Design: Patients with stage I and II invasive carcinomas who underwent partial mastectomy were divided into 2 groups based on whether they were treated before (PRE) or after (POST) guideline publication in March 2014. Groups were compared with respect to re-excision rates, conversion to mastectomy, specimen volumes, mean cost per patient of surgical care, and prospectively collected patient post-procedure quality of life.

Results: A total of 237 patients who underwent partial mastectomy were examined (n = 126 in the PRE group and n = 111 in the POST group). Patients in the POST group were less likely to require re-excision (9% POST vs 37% PRE; p < 0.001) and were less likely to undergo conversion to mastectomy (5% POST vs 14% PRE; p = 0.02). After consensus guideline publication, mean operative cost per patient decreased ($4,874 POST vs $5,772 PRE; p < 0.001), and patients had improved breast quality of life scores (77 out of 100 POST vs 61 out of 100 PRE; p = 0.03). On multivariable analysis, publication of the consensus statement was an independent predictor of decreased re-excision rates (odds ratio 0.17; 95% CI 0.08 to 0.38; p < 0.001) and operative cost per patient (odds ratio 0.14; 95% CI 0.78 to 0.30; p < 0.001).

Conclusions: Widespread implementation of the consensus guideline on margins for breast conserving operation will likely lead to the intended improvements in operative and financial outcomes, as well as patient satisfaction with breast conserving operation.