The mastectomy rate for DCIS is increasing in an equal-access healthcare system

Tawakalitu Oseni Oseni, MD¹, Cary Goepfert, MD¹, Ryan Rockhill, MD¹, Louis Rivera, MD¹, Peter Soballe, MD². ¹Naval Medical Center San Diego, ²Unifromed Services University

BACKGROUND: The increased rates of prophylactic mastectomy have been well documented in the treatment of invasive breast cancer.  However women with early stage breast cancer are usually included in this group despite having a better prognosis.  The goal of this study was to discover whether this trend was present for non-invasive breast cancer in an equal-access model, and to examine the impact of preoperative surgical evaluations on the choice of operation

METHODS: Our institutional tumor registry was queried for this retrospective review study. Eligible women included all diagnosed and treated for ductal carcinoma in situ (DCIS) at our institution from 2007-2013. We identified the yearly prophylactic mastectomy rate and also the use of MRI and plastic-surgery consultation in the preoperative evaluation of all patients.

RESULTS: We identified 189 women with DCIS; 174 were available for analysis. The unilateral and contralateral prophylactic mastectomy (CPM) rates were 17.8% and 11.5% respectively. The CPM rate increased by 380% from 2007 (5.3%) to 2013 (20%). The use of preoperative MRI and plastic surgery consultation increased significantly in this period by over 200% and 400% respectively.  However, this increase was asymmetrically distributed among surgical groups.  Overall only 5.7% of patients undergoing breast conservation had a preoperative MRI compared to 30% of women undergoing CPM (p <0.001).  Similarly, 11.4% of women undergoing breast conservation had a preoperative plastic-surgery consultation compared to 90% of women undergoing CPM (p <0.001).  Young age, African American and Filipina races were significantly associated with a higher CPM rate.

CONCLUSION: In an equal-access health care model the use of prophylactic mastectomy in the treatment of DCIS has steadily increased as it has for invasive cancer.  Preoperative use of MRI and plastic-surgery consultation is clearly associated with this trend.  Individual surgeon preoperative evaluation practices impact patients’ operative decisions