Extensive Disease

Ductal carcinoma in situ (DCIS) accounts for approximately 20% of newly diagnosed breast cancer cases. Of these women, 20% require radical management in the form of mastectomy because of the extent of the lesions, which most often manifest as diffuse microcalcifications. This mutilating surgical management contrasts with the excellent prognosis of this pathology and considerably alters the quality of life of patients. Neoadjuvant hormone therapy has shown its efficacy in hormone-dependent infiltrating ductal carcinomas and offers the possibility of conservative surgery after hormone therapy. Adjuvant hormone therapy with Tamoxifen or anti-aromatase drugs has shown its efficacy in the prevention of homo or contralateral recurrence. The HORNEO 01 trial fits perfectly in the current context of surgical de-escalation of ductal carcinomas in situ. The objective of the study is to evaluate the impact of neoadjuvant hormone therapy on the surgical management of extensive DCIS.