A mastectomy is a breast ablation. It can be partial (only the affected part is removed), or total (the entire breast is removed), when the tumor is too large in relation to the volume of the breast, when there are several lesions, or in the retro-areolar forms.
Advocates of breast cancer screening argue that with the detection of smaller lesions, there is less aggressive treatment on women's breasts, and therefore less heavy surgery is performed. However, several studies and particularly meta analysis have shown the opposite.
(A meta-analysis is a method of combining the results of several independent studies on the same topic in order to synthesize the results and draw an overall conclusion.) Furthermore, the independent review Prescrire, the meta-analysis by the Nordic Cochrane research group, the publication by Pr P. Autier and the american Harding study all report an increase in the number of surgical procedures. The more we detect, the more breasts are removed.
We have verified this ourselves with our study on mastectomies in France, which you will find in its completeness as well as the explanations on the site. Its results are indisputable: no reduction in mastectomies, total or partial, can be demonstrated after the generalization of organized screening.
Irrespective of this fact, what is at stake for women is not to promise them "lighter" surgical acts, but rather not to have them undergo any surgical treatment if they do not need it, while not exposing them unnecessarily to a disease which they should never have known in the absence of screening (over-diagnosis).