Clinical Research Directory

Inclusion Criteria: * women ≥ 18 years of age * histologically proven unilateral primary non-metastatic invasive breast cancer * Estrogen receptor (ER)-/ or Progesterone receptor (PR)- positive and HER2-negative * Ki67 from core biopsy is available * no lymph-node involvement by clinical evaluation and ultrasound (cN0) * not amendable to neoadjuvant chemotherapy * surgery or planned surgery at the Department for Women's Health, Tuebingen or Freiburg * planned preoperative endocrine treatment with Tamoxifen, Aromatase inhibitors, Goserelin or nothing for 2 - 4 weeks * written informed consent Exclusion Criteria: * ER-negative and PR-negative * HER2-positive * bilateral breast cancer * preexisting cancer disease within the last 10 years * preexisting invasive ipsi- or contralateral breast cancer (non-invasive ipsi- or contralateral breast cancer is not regarded as an exclusion criteria) * any systemic breast cancer therapy before inclusion into the trial * indication for neoadjuvant chemotherapy * any systemic therapy except Tamoxifen, Aromatase inhibitors, Goserelin before surgery * locally advanced, inoperable or metastatic breast cancer * pregnant or lactating patients * inadequate general condition (not fit for chemotherapy) * hormonal contraception within 6 months before inclusion