MRI screening in a clinic population with a family history of breast cancer

Background: Breast MRI is increasingly being used in patients at increased risk for breast cancer; however, guidelines for MRI screening are inadequately defined. We describe our experience with MRI screening in a large population of women with a family history of breast cancer. Methods: We retrospectively reviewed the Memorial Sloan-Kettering breast cancer surveillance program prospective database from April 1999 to July 2006. Patients with a family history of breast cancer and at least 1 year follow-up were identified. All patients were offered biannual clinical breast examination (CBE) and annual mammography (MMG). MRI screening was performed at the discretion of the physician and patient. Results: Family history profiles revealed 1,019 eligible patients; median follow-up was 5.0 years. MRI screening was performed in 374 (37%) patients resulting in a total of 976 MRIs during the study period. Cancer was detected in 9/374 patients (2%) undergoing MRI screening. Seven cancers were detected by MRI only, for a cancer detection rate of 0.7% (7/976) for screening MRI. When stratified by family risk profile, the positive predictive value (PPV) of MRI was higher (13%) in those patients with the strongest family histories and lower (6%) in patients with less significant family histories. Conclusions: MRI screening can be a useful adjunct to CBE and MMG in patients with high-risk family histories of breast cancer, yet it has low yield in patients with lower-risk family histories. These data suggest that MRI screening should be reserved for those at highest risk.