HYPOG-01: Dr. Sofia Rivera

Hypofractionated radiotherapy (15 sessions / 3 weeks) versus conventional fractionation (25 sessions / 5 weeks) for patients with locoregional breast cancer: a multicenter randomized phase III trial (HYPOG-01 – Unicancer / UNITRAD)

The HYPOG-01 study, promoted by Unicancer and led by Dr. Sofia Rivera, radiation oncologist at Gustave Roussy and President of the UNITRAD group, was presented during a presidential session at the ESMO 2024 congress.

This multicenter randomized phase III trial compared two radiotherapy regimens after surgery in 1,265 patients with locoregional breast cancer:

• Hypofractionated schedule: 15 sessions over 3 weeks (40 Gy)
• Conventional schedule: 25 sessions over 5 weeks (50 Gy)

Results show that the shorter 3-week radiotherapy schedule provides equivalent efficacy to the standard 5-week treatment, without increasing side effects. No increased risk of lymphedema was observed, and rates of locoregional relapse-free survival, overall relapse-free survival, and overall survival were similar in both arms.

Implemented in 29 French centers between 2016 and 2020, this study demonstrates, for the first time in a prospective and randomized setting, that a hypofractionated radiotherapy regimen can be safely applied to patients with node-positive breast cancer.
The findings of HYPOG-01 represent a major shift in the international standard: breast cancer radiotherapy will now last no more than three weeks, improving patient comfort and the efficiency of radiotherapy services.

About Dr. Sofia Rivera

Sofia Rivera is a radiation oncologist at Gustave Roussy and President of the UNITRAD group (Unicancer). A specialist in breast cancer and hypofractionated approaches, she conducts academic clinical trials aimed at shortening treatment while preserving efficacy.
Committed to clinical research and the dissemination of new standards, she contributes to positioning France as a reference in oncological radiotherapy, advancing more personalized and patient-centered care.