Clinical trial for early breast cancer ER positive, HER2 negative

Thank you @apples56. I really appreciate your response. I have read through the information sent to me (23 pages) and will have a chat with the research nurse today in the afternoon. It was a bit of a shock because my oncologist never mentioned this before and gave me a prescription for letrozole to start on 12 August. I understand that I can be randomized to the standard arm, but I am not sure that I want to participate in the tests beforehand. Initially, I thought, why not participate and be monitored for free? But aren't all others monitored for being on standard medication? I am really tired of going through all the treatments and wanted to have a break from the tests that the trial will involve. I cannot make a decision easily, but maybe the chat with the nurse will help me decide.