After briefly mentioning the incidence of in situ breast carcinoma and the importance of mammography as an instrument of early diagnosis, the Authors inspect their own case notes and discuss indications and problematical characters linked to the various surgical techniques. It is concluded that, in case of a not infiltrating mammary carcinoma, it is possible to entertain an adequate conservative surgical treatment on condition that it is always associated to a modern and effective radiotherapy of the remaining mammary parenchyma and that it is feasible an attentive and extended follow-up; when even only one of these two conditions is not practicable or in the presence of cancer-phobic patients, the alternative of a unilateral or bilateral subcutaneous mastectomy, followed by an immediate reconstruction with an implant, does remain efficacious both on the oncological and esthetic point of view.