Abiraterone Acetate in Molecular Apocrine Breast Cancer

Screening : All women 18+, with a confirmed locally advanced or metastatic Triple Negative Breast Cancer (TNBC), will be screened and invited to participate (300-500 patients). Only patients with a centralized confirmation of ER-/PR-/HER2- and evaluation of AR+ will be included and treated with abiraterone acetate plus prednisone (31 patients). The Treatment phase comprises a series of 4 weeks-cycles with continuous study treatment. Study drug treatment will continue until the earliest of the following events: disease progression, unacceptable toxicity, or death. At disease progression, patients must be discontinued from study drug and should be evaluated within 30 days during the Post treatment visit and then entered into the Follow-Up phase.Patients should enter the Follow-Up Period regardless of reason for study drug discontinuation and should be monitored every 3 months (± 7 days) during 2 years.