This study is for young women with stage I-III breast cancer taking hormone therapy. Hormone therapy is a treatment that uses medicines to block or lower hormones that help cancer grow. This study checks if monitoring symptoms helps women stay on their medication. There are two groups in this study. One group will get regular education about breast cancer and how to handle side effects. The other group will get the same education plus weekly questions about any symptoms they have. This helps doctors see if asking about symptoms more often helps women keep taking their medicine.

Key Points:

• Study lasts 80 weeks with regular check-ins.
• Participants might be asked questions about symptoms weekly.
• Participants may submit blood samples for research.

Women can join if they have stage I-III breast cancer, are pre- or peri-menopausal, and have started or plan to start hormone therapy within 14 days of joining. They must be able to answer questions online or by phone. Pregnant women or those with other cancers cannot join.