Breast MR imaging for extent of disease assessment in patients with newly diagnosed breast cancer.

Breast cancer staging and surgical planning are affected by the burden of pathologically proven cancer detected on clinical examination and/or imaging. Magnetic resonance (MR) imaging has superior sensitivity and accuracy for the detection of invasive and in situ breast cancer as compared with physical examination, mammography, and ultrasound but can be limited in specificity. The use of preoperative breast MR imaging for evaluating the extent of disease remains controversial at present because studies have not definitively shown it to improve overall survival, decrease re-excision rates, or to decrease the cost of care.