Neoadjuvant Endocrinotherapy of Breast Cancer (Mamma Carcinoma) With Exemestane

Inclusion Criteria: * Histologically verified breast cancer (punch biopsy), established HER-2/neu status * Postmenopausal patients (\> 1 year following outset of menopause and/or postmenopausal hormonal profile) * Clinical staging: T2 (\> 3 cm), T3, T4a-c, N0-1 * Hormone receptor positivity, i.e. estrogen and/or progesterone receptor \> 10 fmol/mg cytosolic protein or ER-ICA-positive and/or PgR-ICA-positive. Positivity of + (low-grade) in one hormone receptor is only eligible in the presence of positivity in the other hormone receptor. * no internal contraindication * life expectation \> 6 month * written informed consent Exclusion Criteria: * premenopausal patients and patients with no clearly indicated menopausal status * manifest second malignant tumor (except basalioma or in situ carcinoma of cervix uteri) * uncontrolled internal disease i.e. diabetes mellitus, cardiac disease (NYHA III/IV) * thromboembolic disease * inflammatory mamma carcinoma * existence of distant metastases * former or simultaneously therapy with antioestrogens, aromatase inhibitors, cytostatics or radiotherapy * corticosteroids before and during the study (except inhalant application) * lack of compliance