In 141 mastectomy specimens, performed for invasive or noninvasive carcinomas, histopathologic study was performed to assess the extent of nipple-areola involvement by the tumor. In this study, patients were excluded if (1) the tumor was located beneath the areola; and (2) nipple and/or areola abnormalities were clinically present. Tumor involvement of the nipple and/or areola was found in 44 of 141 specimens (31%), with intraductal growth in 36 (82%) of 44, stromal invasion in 3 (7%), and ductal and stromal invasion in 5 (11%). Analysis of nipple-areolar involvement with consideration of the different variables indicates that it occurred in association with tumor size, tumor-areola distance, and histologic type. Such information provides clinically relevant guidelines in decision making for limited breast surgery.