Hypofractionated versus conventional fractionated postmastectomy radiotherapy for patients with high-risk breast cancer (CHN HYPOPMRT): 10-year outcomes from a randomised, non-inferiority, open-label, phase 3 trial.

In 30 seconds

This phase 3 randomized trial compared hypofractionated (43.5 Gy in 15 fractions) and conventional (50 Gy in 25 fractions) postmastectomy radiotherapy in 810 women with high-risk breast cancer. At 10 years, locoregional recurrence rates were 10.3% for conventional and 12.0% for hypofractionated radiotherapy, with a hazard ratio of 1.19, indicating non-inferiority.

Key findings

• At 10 years, cumulative locoregional recurrence was 10.3% for conventional vs 12.0% for hypofractionated radiotherapy.
• The median follow-up duration was 11.5 years.
• No grade 4-5 adverse events or treatment-related deaths occurred in either group.
• The most common grade 3 adverse events were ischaemic heart disease and lymphoedema, both occurring in 1% of patients.

Why it matters

The findings support hypofractionated radiotherapy as a time-efficient alternative to conventional fractionation, providing similar long-term locoregional control and safety profiles, which may influence treatment planning for high-risk breast cancer patients.