['breast cancer', 'hormone receptor positive tumor', 'early-stage breast carcinoma']
['abemaciclib', 'loperamide', 'anastrozole']

        Inclusion Criteria:

          -  Have postmenopausal status.

          -  Adenocarcinoma of the breast.

          -  Breast tumor ≥1 centimeter (cm) in diameter, HR+, HER2-.

          -  Neoadjuvant endocrine monotherapy is deemed to be a suitable therapy.

          -  Primary breast cancer that is suitable for baseline core biopsy.

          -  Have adequate organ function.

        Exclusion Criteria:

          -  Bilateral invasive breast cancer.

          -  Metastatic breast cancer (local spread to axillary lymph nodes is permitted).

          -  Inflammatory breast cancer.

          -  Prior systemic therapy or radiotherapy for invasive or non-invasive breast cancer in
             the same breast as currently being treated.

          -  Prior radiotherapy to the ipsilateral chest wall for any malignancy.

          -  Prior anti-estrogen therapy.
      