Predicting nipple-areolar involvement using preoperative breast MRI and primary tumor characteristics.

Abstract

40 Background: Preoperative assessment of the nipple-areolar complex (NAC) is invaluable when considering nipple-sparing mastectomy (NSM). We hypothesized that breast MRI could predict involvement of the NAC with tumor. Methods: We compiled clinical, pathologic and imaging data for patients who underwent preoperative breast MRI followed by mastectomy or NSM between 2006 and 2009. Blinded rereview of all MRI studies was performed by a breast MRI imager and compared to initial MRI findings. Multivariate analysis identified variables predicting NAC involvement with tumor. Results: Of 77 breasts, 18 (23%) had tumor involving or within 1 cm of the NAC. The sensitivity of detecting pathologically confirmed NAC involvement was 61% with history and/or physical exam, and 56% with MRI. Univariate analysis identified the following variables as significant for NAC involvement: large tumors close to the nipple on preoperative MRI, node-positive disease, invasive lobular carcinoma, advanced pathologic T stage, and neoadjuvant chemotherapy. On multivariate analysis, only tumor size > 2 cm and distance to the NAC < 2 cm on MRI maintained significance. Pearson correlation coefficient for MRI size compared to pathologic size was 0.53 (p<0.0001). Conclusions: MRI is not superior to thorough clinical evaluation for predicting tumor in or near the NAC. However, MRI-measured tumor size and distance from the NAC are correlated with increased risk of NAC involvement. Preoperative history and physical examination, tumor characteristics, plus breast MRI can aid the surgeon in planning for successful NSM.