Study Finds Radiotherapy May Be Unnecessary After Mastectomy in Early Breast Cancer

An international clinical trial led by the University of Edinburgh has found that women with early-stage, intermediate-risk breast cancer who undergo mastectomy and modern anti-cancer therapy can safely avoid radiotherapy without affecting long-term survival.

The SUPREMO trial, involving 1,607 patients from 17 countries, compared outcomes between women who received chest wall radiotherapy and those who did not. After 10 years of follow-up, survival rates were nearly identical—81.4% with radiotherapy versus 81.9% without—with no differences in disease-free or metastasis-free survival.

Researchers noted that improved systemic treatments have reduced the need for radiotherapy, which showed minimal impact on recurrence and mild side effects. However, the findings apply only to intermediate-risk patients, not those with higher recurrence risk.

Funded by the MRC-NIHR partnership, the study offers strong evidence to spare many patients unnecessary treatment, improving care efficiency and quality of life.

10-11-2025