Changes in the surgical management of patients with breast carcinoma based on preoperative magnetic resonance imaging.

BACKGROUND Breast magnetic resonance imaging (MRI) is a developing technique for the evaluation of patients with primary breast carcinoma. The authors assessed the impact of preoperative breast MRI on surgical management. METHODS The current study was a retrospective review of 267 patients with primary breast tumors who had MRI studies prior to undergoing definitive surgery. RESULTS Two hundred sixty-seven patients with invasive breast carcinoma who had preoperative breast MRI studies and had complete clinical, radiologic, and pathologic data available were identified and formed the basis of this analysis. The overall sensitivity of MRI for detecting primary, intact breast tumors was 95%. Planned surgical management was altered in 69 of 267 patients (26%); and, in 49 of those patients (71%), there was pathologic verification of malignancy in the surgical specimen that confirmed the need for wider or separate excision or mastectomy. Forty-four of 267 patients (16.5%) had conversion of planned breast conservation to mastectomy. In a univariate analysis, change in management was associated significantly with histology; management was altered in 11 of 24 lobular tumors (46%) compared with 58 of 243 ductal tumors (24%; P = 0.02). CONCLUSIONS Breast MRI was very sensitive for the detection of primary, intact, invasive breast carcinoma and improved local staging in almost 20% of patients. Preoperative breast MRI studies may be particularly useful in surgical planning for and management of patients with lobular carcinoma.