Open Label Trial for Post-Menopausal Women With Newly Diagnosed Operable Breast Cancer

This is an open label, single arm, and Phase II study of the combination of Letrozole and Bevacizumab in patients with newly diagnosed breast cancer. Patients meeting the eligibility criteria and who have signed the consent form will start Letrozole 2.5 mg by mouth a day and Bevacizumab 15 mg per Kg IV every 3 weeks for 18 weeks (24 weeks if still responding at week 18 if approved by the PI). After neoadjuvant therapy, participants will undergo surgical treatment and will receive adjuvant therapy according to the treating physician.