Radiation Therapy after Mastectomy?
New study finds many Breast Cancer patients may not need Radiation after Mastectomy
A major international trial suggests that some women can safely skip chest-wall radiation without affecting survival.
For many women with breast cancer, the word “radiation” can bring fear and uncertainty. After a mastectomy, radiation therapy to the chest area is often recommended to reduce the risk of the cancer coming back. But new research shows that some women may not actually need it.
What the study looked at
An international research team recently published the results of the SUPREMO trial in the New England Journal of Medicine.
The study involved nearly 1,600 women who had undergone a mastectomy, axillary lymph node dissection, and modern cancer treatments such as chemotherapy or hormone therapy.
80% of the women had breast cancer which spread to 1-3 lymph nodes which usually is an indication for radiotherapy.
The women were randomly assigned to two groups:
Group 1 received radiation therapy to the chest wall
Group 2 did not receive radiation
The main findings
After ten years, the results were almost identical in both groups:
- About 82% of women in each group were still alive.
- The number of women who had their cancer come back elsewhere in the body was nearly the same.
- Only a small difference was seen in local recurrences (cancer returning in the chest area):
1.1% of women with radiation vs. 2.5% without radiation.
In other words — radiation made a very small difference in preventing local recurrences, but did not improve overall survival.
Why This Matters
This is good news for many women with early-stage, intermediate-risk breast cancer. The study suggests that radiation after mastectomy may not always be necessary, especially when patients have already received effective systemic treatments.
Skipping radiation can mean:
- Fewer side effects such as fatigue, skin irritation, and long-term tissue changes
- Shorter treatment times
- A better overall quality of life
What patients should know
These findings don’t mean radiation should be avoided in all situations — but they give doctors and patients stronger evidence to make personalized decisions together.
If you’ve had a mastectomy, make an appointment with us to discuss your individual risk factors and whether post-surgery radiation is truly needed for you.
Reference
The SUPREMO Trial, New England Journal of Medicine, 2025. Funded by the Medical Research Council and others (ISRCTN 61145589).
Trial details: https://pubmed.ncbi.nlm.nih.gov/41191939/