Study on Pre-Operative Endocrine Therapy to Guide Radiation Treatment Decisions in Older Women with Early Stage Breast Cancer (POWER II)

Program Overview

This Phase III study is for women aged 65 and older with early stage estrogen receptor positive (ER+) breast cancer. Participants will be randomly assigned to one of two groups: one group will receive 3 months of hormone therapy before surgery, while the other group will follow the usual care and go directly to surgery. The study will assess how well patients tolerate the hormone therapy and how it affects their treatment decisions regarding radiation therapy.

Description

In early stage estrogen receptor positive (ER+) breast cancer, treatment usually involves breast conserving surgery (BCS), radiation therapy (RT), and 5-10 years of hormone therapy. For women aged 65 and older with small, node-negative ER+ breast cancer, skipping radiation therapy is an option, but many still receive it, which may lead to over-treatment. Some patients who skip radiation may not tolerate hormone therapy well, risking under-treatment.

The POWER I trial showed that 90 days of hormone therapy before surgery helped patients and doctors decide on radiation therapy. The POWER II trial will randomly assign participants to either receive 90 days of hormone therapy before surgery or go directly to surgery. The decision to use radiation therapy will be made by the patient and doctor. All patients will be recommended hormone therapy if suitable, and adherence will be monitored for 2 years. The study aims to see if pre-surgery hormone therapy reduces the number of patients receiving surgery alone or surgery with radiation and hormone therapy. Adherence to hormone therapy will be checked 2 years after surgery.

Eligibility Criteria