Locoregional treatment of breast cancer in women with and without preoperative magnetic resonance imaging

Abstract

Background Preoperative magnetic resonance imaging (MRI) use has increased among older women diagnosed with breast cancer. MRI detects additional malignancy, but its impact on locoregional surgery and radiation treatment remains unclear. Methods We examined the associations of preoperative MRI with initial locoregional treatment type (mastectomy, breast conserving surgery (BCS) with radiation therapy (RT), BCS without RT) and BCS reoperation rates for SEER-Medicare women diagnosed with stage 0–III breast cancer from 2005–2009 (N=55,997). Results We found no association of initial locoregional treatment of mastectomy (OR 1.04, 95% CI (0.98–1.11)) or reoperation after initial BCS (OR 0.96, 95% CI (0.89–1.03)) between women with preoperative MRI (16.2%) compared to women without MRI. However, women with MRI who had initial BCS were more likely to undergo RT (OR 1.09 (1.02–1.16)). Conclusion Preoperative breast MRI in Medicare-enrolled women with stage 0–III breast cancer was not associated with increased mastectomy. However, in older women with MRI undergoing BCS, there was a greater use of RT.