BACKGROUND:Evidence-based guidelines recommend limited perioperative diagnostic imaging for new breast cancer diagnoses. For patients aged >65 years, conventional imaging use (mammography, plain radiographs, and ultrasound) has remained stable, whereas advanced imaging (computed tomography [CT], nuclear medicine scans [positron emission tomography/bone scans], and magnetic resonance imaging [MRI]) use has increased. In this study, the authors evaluated traditional and advanced imaging use among younger patients (aged ≤ 65 years) undergoing breast cancer surgery. METHODS:The MarketScan Commercial Claims and Encounters Research Database from 2005 through 2008 was analyzed to evaluate the use of conventional and advanced diagnostic imaging associated with surgery for ductal carcinoma in situ (DCIS) or stage I through III invasive breast cancer. RESULTS:The study cohort included 52,202 women (13% with DCIS and 87% with stage I-III breast cancer). The proportion of patients undergoing conventional imaging remained stable, whereas the average number of conventional imaging tests per patient increased from 4.21 tests in 2005 to 4.79 tests per patient in 2008 (P < .0001). For advanced imaging, the proportion of women who underwent imaging increased from 48.8% in 2005 to 68.8% in 2008 (P < .0001), as did the number of tests per patient (from 1.53 tests in 2005 to 1.98 tests in 2008; P < .0001). MRI examinations accounted for nearly all of the increase in advanced imaging. Patients who underwent MRI examinations received significantly more traditional imaging tests compared with to those who did not, indicating that these tests are additive and are not replacing traditional imaging. CONCLUSIONS:The current results demonstrate that the use of perioperative breast MRI has increased among women aged <65 years. Further study is indicated to determine whether the benefits of this procedure justify increased use.