Neo-adjuvant Therapy With Anastrozole Plus Pazopanib in Stage II and III ER+ Breast Cancer

OBJECTIVES: I. To determine the pathologic complete response (pCR) rate at surgery. SECONDARY OBJECTIVES: I. To evaluate alternative measurements of anti-tumor activity: proportion of patients achieving sustained decrease in antigen KI-67 (ki-67) at 12 weeks of therapy with anastrozole plus pazopanib (pazopanib hydrochloride); proportion of patients achieving down-staging to a pathologic stage 0 or 1 at surgery. II. To assess qualitative and quantitative toxicity of this combination, with special emphasis on the frequency of events grade 3 or greater, or the occurrence of unexpected toxicities. OUTLINE: Patients receive pazopanib hydrochloride\* orally (PO) once daily (QD) and anastrozole PO QD for 6 months in the absence of disease progression or unacceptable toxicity. Patients then undergo definitive surgery. NOTE: \*Pazopanib hydrochloride is stopped 7-14 days before surgery.