Impact of Aromatase Inhibitor Therapy on Glucose Homeostasis and Diabetes Risk

This study is investigating whether aromatase inhibitors — a common hormone-blocking medication used for breast cancer — affect blood sugar levels and increase diabetes risk in postmenopausal women with hormone receptor positive breast cancer or high-risk breast conditions. **You may be eligible if...** - You are a postmenopausal woman (no period for 12 months, or had both ovaries removed) - You have hormone receptor positive breast cancer, DCIS (early-stage breast cancer), or a high-risk breast condition - You are planning to start or recently started aromatase inhibitors (within 6 months), OR you are starting Tamoxifen, OR you are a healthy postmenopausal woman for comparison **You may NOT be eligible if...** - You already have a diabetes diagnosis - You are taking medications that affect blood sugar - Your fasting glucose is already above 126 mg/dL or HbA1c ≥ 6.5% - You have had stomach or intestinal surgery that affects how food is absorbed (like bariatric surgery) Talk to your doctor to see if this trial is right for you.