Current guidelines recommend endocrine treatment with aromatase inhibitors (AIs) in post-menopausal women with hormone receptor-positive breast cancer. Musculoskeletal symptoms are commonly reported with AI treatment,however, we do not have consistent methods to measure these symptoms prospectively. This gap in our knowledge inhibits the ability to test and develop treatments for AI-associated musculoskeletal symptoms. This pilot study will evaluate functional tests and standardized instruments for their ability to prospectively assess musculoskeletal symptoms in women being treated with AIs for breast cancer.

Specific Aims: 1) identify a core set of instruments for measuring musculoskeletal symptoms, 2) model the time course and predictors of change in musculoskeletal symptoms, 3) explore the effect of musculoskeletal symptoms on adherence to AIs in women during the first 6 months of AI treatment.

Methods: We will prospectively assess musculoskeletal symptoms due to treatment with aromatase inhibitors. Post-menopausal women beginning AI treatment for hormone responsive breast cancer will be invited to join this study.

Inclusion Criteria:

• Women with stage I - IIIa invasive breast cancer,
• Hormone-receptor positive cancer (either ER+ or PR+ or both),
• Prescribed and have agreed to take exemestane, anastrazole or letrozole,
• Have completed initial treatment of surgery, RT, and/or chemotherapy,
• Are post-menopausal,
• No previous history of aromatase inhibitor therapy for invasive breast cancer,
• Have signed the consent form.

Exclusion Criteria:

• History of rheumatoid arthritis,
• Unable to read or understand English,
• History of psychiatric disability affecting informed consent or compliance with study procedures.

Post-menopausal breast cancer patients receiving aromatase inhibitors