Trends in Reoperation After Initial Lumpectomy for Breast Cancer Addressing Overtreatment in Surgical Management

IMPORTANCE Surgery after initial lumpectomy to obtain more widely clear margins is common and may lead to mastectomy. OBJECTIVE To describe surgeons' approach to surgical margins for invasive breast cancer, and changes in postlumpectomy surgery rates, and final surgical treatment following a 2014 consensus statement endorsing a margin of no ink on tumor. DESIGN, SETTING, AND PARTICIPANTS This was a population-based cohort survey study of 7303 eligible women ages 20 to 79 years with stage I and II breast cancer diagnosed in 2013 to 2015 and identified from the Georgia and Los Angeles County, California, Surveillance, Epidemiology, and End Results registries. A total of 5080 (70%) returned a survey. Those with bilateral disease, missing stage or treatment data, and with ductal carcinoma in situ were excluded, leaving 3729 patients in the analytic sample; 98% of these identified their attending surgeon. Between April 2015 and May 2016, 488 surgeons were surveyed regarding lumpectomy margins; 342 (70%) responded completely. Pathology reports of all patients having a second surgery and a 30% sample of those with 1 surgery were reviewed. Time trends were analyzed with multinomial regression models. MAIN OUTCOMES AND MEASURES Rates of final surgical procedure (lumpectomy, unilateral mastectomy, bilateral mastectomy) and rates of additional surgery after initial lumpectomy over time, and surgeon attitudes toward an adequate lumpectomy margin. RESULTS The 67% rate of initial lumpectomy in the 3729 patient analytic sample was unchanged during the study. The rate of final lumpectomy increased by 13% from 2013 to 2015, accompanied by a decrease in unilateral and bilateral mastectomy (P = .002). Surgery after initial lumpectomy declined by 16%(P < .001). Pathology review documented no significant association between date of treatment and positive margins. Of 342 responding surgeons, 69% endorsed a margin of no ink on tumor to avoid reexcision in estrogen receptor-positive progesterone receptor-positive cancer and 63% for estrogen receptor-negative progesterone-receptor-negative cancer. Surgeons treating more than 50 breast cancers annually were significantly more likely to report this margin as adequate (85%; n = 105) compared with those treating 20 cases or fewer (55%; n = 131) (P < .001). CONCLUSIONS AND RELEVANCE Additional surgery after initial lumpectomy decreased markedly from 2013 to 2015 concomitant with dissemination of clinical guidelines endorsing a minimal negative margin. These findings suggest that surgeon-led initiatives to address potential overtreatment can reduce the burden of surgical management in patients with cancer.