Applicability of the nipple-areola complex-sparing mastectomy: a prediction model using mammography to estimate risk of nipple-areola complex involvement in breast cancer patients

The purpose of this study was to develop a prediction model that can be used to identify breast cancer patients at lowest risk for neoplastic nipple-areola complex (NAC) involvement to offer total NAC-sparing mastectomy with immediate reconstruction. Medical records, pathology slides, and mammograms were reviewed for all breast cancer patients treated with total mastectomy at Rhode Island Hospital between 2000 and 2004. The distance between the nipple and the closest tumor margin was measured using mammography. NAC involvement was identified in 42% of the 31 study patients. Mammographic distance, pathologic stage, and tumor size were identified as independent predictors of malignant NAC involvement by multivariate analysis (rho < 0.05). Based on these predictors, a linear discriminant score, the NAC Involvement Score (NACIS), was computed to distinguish between the presence and absence of NAC involvement. For individual patients, positive NACIS values (> or = -0.3665) were associated with NAC involvement with a sensitivity of 92%, specificity of 77%, and negative predictive value of 93%. These preliminary findings indicate that the NACIS formula may be a useful clinical tool for selecting low-risk patients for total NAC-sparing mastectomy with immediate reconstruction.