Patient age and tumor size determine the cancer yield of preoperative bilateral breast MRI in women with ductal carcinoma in situ

The objective of our study was to determine the cancer yield of preoperative breast MRI in women with newly diagnosed ductal carcinoma in situ (DCIS) and to identify subgroups of DCIS patients for whom MRI is more likely to identify additional cancers.A database search for patients with DCIS who had undergone breast surgery between 2007 and 2011 was performed. A total of 308 women (median age, 49 years; range, 25-82 years) with DCIS underwent mammography, sonography, and a preoperative evaluation with MRI. The cancer yield and positive biopsy rate were determined. Patient age at diagnosis, menopausal status, family history of breast cancer, mammographic breast density, index cancer size, nuclear grade, and estrogen receptor (ER) status were examined, and a multivariate logistic regression analysis was performed.The cancer yield was 8% (24/308), and the positive biopsy rate was 53% (24/45). Of the 24 additional cancers, 14 (58%) represented multifocal disease, two (8%) represented multicentric disease, and eight (33%) represented contralateral cancer. In a multivariate analysis, age and index cancer size were factors significantly associated with additional MRI-detected cancers. Compared with women≥50 years, women50 years had a 3.2-fold higher frequency of detection (95% CI, 1.2-8.9; p=0.02). Compared with women with DCIS lesions smaller than 2.5 cm, women with DCIS lesions 2.5 cm or larger showed a 2.6-fold higher frequency of detection (95% CI, 1.1-6.3; p=0.04).Preoperative breast MRI can be considered in patients with DCIS who are50 years old, have index cancers≥2.5 cm, or fulfill both criteria.