ERBB2 and ductal breast carcinoma in situ: When comparing the patients and the tumor characteristics, no significant differences between tumorectomies with and without IWSM were found regarding menopausal status, PST use, history of radiotherapy on the affected breast, grading of the tumor, tumor size at pathological analysis, hormonal receptor status and Her2 expression of the tumor, histological type of the tumor (ductal, lobular, or other), and DCIS or invasive breast cancer.