A Study to Evaluate Genetic Predictors of Aromatase Inhibitor Musculoskeletal Symptoms (AIMSS)

PRIMARY OBJECTIVES: I. To validate previously identified associations between 10 specific single nucleotide polymorphisms (single nucleotide polymorphisms \[SNPs\]) and discontinuation of treatment with aromatase inhibitors (AIs) due to the development of musculoskeletal symptoms (MSS) among women with breast cancer. SECONDARY OBJECTIVES: I. To determine whether other SNPs in cytochrome P450 enzymes (CYP), glucuronosyltransferases (UGT), Vitamin D, serotonin and other receptors are associated with discontinuation of treatment due to the development of severe aromatase inhibitor-associated musculoskeletal symptoms (AIMSS). II. To determine whether other SNPs in CYP, UGT, Vitamin D, serotonin and other receptors are associated with the development of other potential complications of AI therapy. III. To develop a gene signature that can identify patients at risk for developing severe anastrozole-related AIMSS and other potential complications of AI therapy. IV. To determine the epidemiology and predictors of severe AIMSS and of AI discontinuation. V. To describe patient reported outcomes for minority patients with breast cancer treated with AIs. VI. To assess the utility of the Patient Reported Outcomes Management Information System (PROMIS) system to collect patient reported outcomes in a cooperative group study, and validate the PROMIS Physical Function 20a form in patients with AIMSS. VII. To develop a model that incorporates patient ratings of treatment burden, fear of recurrence and adherence behaviors to describe patient decisions to continue or discontinue anastrozole. VIII. To collect serum samples for future testing for biomarkers of AIMSS. OUTLINE: Patients receive anastrozole orally (PO) once daily (QD) for 12 months. After the completion of study treatment, patients are followed up for 12 months.