Submission Date (or date of most recent update)
March 18, 2025
Trial Name
“A Randomized, Phase III Trial of Pre- Operative Window of Endocrine Therapy to Inform Radiation Therapy Decisions in Older Women with Early-Stage Breast Cancer (POWER II)”
Principal Investigator
Shayna Showalter, MD
University of Virginia
Email: snl2t@uvahealth.org
Phone: 434-242-7078
Trial Type
Investigator-initiated
Date Trial Opened
July 2024
Trial Status
Currently Accruing
Target Accrual
354
Current Accrual (as of date of last update)
13
Brief Summary
Early-stage, estrogen receptor positive (ER+) breast cancer is traditionally treated with breast conserving surgery (BCS), radiation therapy (RT) and 5-10 years of adjuvant endocrine therapy (AET). Radiation therapy (RT) omission is an established treatment paradigm for women 65 years and older with ER+, node negative, small (≤ 3 cm) breast cancer. Despite the option for RT omission being recommended in the National Comprehensive Cancer Network (NCCN) guidelines, multiple modern studies demonstrate that a majority of older women still receive RT, raising concern for over-treatment. Conversely, there are a portion of patients who choose to omit RT but are not able to tolerate AET and thus are at risk for under-treatment and worse oncologic outcomes.
In the POWER I trial, patients were treated with 90 days of pre-operative endocrine therapy (pre-ET) as a window to establish endocrine therapy (ET) tolerance. The POWER I trial prospectively validated 90 days of pre-operative ET to determine if it could be used as a tool to inform adjuvant RT decisions and recommendations by patients and physicians respectively. Ninety days of pre-ET was shown to influence patient and physician preferences regarding adjuvant RT.
In the POWER II trial, participants will be randomized to treatment on either a) an intervention arm consisting of a 90-day window of pre-ET or b) the standard of care (control) arm in which participants proceed directly to BCS. In both arms, the decision to omit or administer adjuvant RT will be made by the treating physicians and patients.
While not required per protocol, all patients will be recommended for AET if deemed appropriate by their oncologist, and adherence through 2 years will be monitored. The purpose of the POWER II study is to examine whether 90 days of pre-ET results in a decrease in the number of (1) patients being treated with BCS alone and (2) patients treated with BCS+RT+AET. Adherence to AET will be defined as taking AET at 2 years post-BCS.
Patient Population
Women 65+ with ER+/HER2- early-stage breast cancer. Looking to increase diversity of participant population from our other sites.
Looking For
Looking to increase diversity of participant population from our other sites. Currently the trial is open at UVA and VCU with goal to include 4 additional sites.
Funding
External funding planned/pending. Current potential to offer participating sites start-up costs and cover study costs with PI philanthropic funds.
NCT#
NCT06507618
