Neoadjuvant Lenvatinib Combined With Letrozole in Hormone Receptor Positive Breast Cancer

Single agent lenvatinib daily continuously x 2 weeks, followed by letrozole 2.5mg daily + lenvatinib x 12 weeks. Lumpectomy or mastectomy should be considered after completing 14 weeks of pre-operative lenvatinib + letrozole for curative intent in non-metastatic patients and for local control for patients with metastatic disease. If surgery is planned, it should preferably be performed within 2-12 weeks after completing neoadjuvant endocrine therapy, and after toxicities (if any) from the neoadjuvant endocrine therapy have resolved. If the patient is deemed inoperable after 14 weeks of lenvatinib + letrozole, a final biopsy will be obtained, and the patient discontinued from the study and treated as per standard clinical practice by the treating physician.