Randomized Phase III Study of Pre-Operative Endocrine Therapy to Guide Radiation Treatment in Women 65 and Older With Early ER Breast Cancer

What this Trial Is About

This trial studies women aged 65 and older with early-stage estrogen receptor positive ER breast cancer. It evaluates whether a 90-day period of pre-operative endocrine therapy pre-ET can help inform decisions about the use of radiation therapy after breast conserving surgery BCS. The study builds on previous findings suggesting that pre-ET can influence patient and physician choices regarding adjuvant treatment. Participants are randomly assigned to one of two groups the intervention group receives 90 days of pre-ET using tamoxifen or an aromatase inhibitor before surgery, while the control group proceeds directly to BCS without pre-ET. After surgery, decisions about radiation therapy and additional endocrine therapy AET are made by patients and their doctors. Treatment adherence to AET is monitored for two years. Throughout the study, participants complete patient-reported outcome surveys to assess tolerance and compliance with endocrine therapy. Researchers track treatment adherence, decision conflict and regret, quality of life, side effects, and long-term cancer outcomes including recurrence and survival over five years. The total participation spans multiple years to capture these long-term effects.

Pre-Operative Window of ET to Inform RT Decisions (POWER II)