The 2026 American Society for Radiation Oncology (ASTRO) Annual Meeting brought together cancer experts from around the world to share new research on how radiation therapy can be used more effectively and personalized to patients’ needs. This year’s research offers more information to help breast cancer patients and their care teams weigh the benefits, risks, and practical considerations of different treatment options.
1) A 3-week radiation schedule may offer long-term cancer control after mastectomy
A 10-year follow-up of the CHN HYPOPMRT trial found that people with high-risk breast cancer could receive radiation after a mastectomy over 3 weeks instead of the usual 5 weeks without reducing long-term cancer control. The chance of the cancer returning in the breast area or nearby lymph nodes was similar between the two treatment schedules, and there were no significant differences in overall survival or disease-free survival. Serious long-term side effects were uncommon and similar between the groups. A shorter radiation schedule means fewer trips to the treatment center while still providing effective long-term treatment for people who need radiation after a mastectomy.
These findings add to growing evidence that shorter radiation schedules can be an option when radiation to the chest wall and nearby lymph nodes is recommended.
2) Less than 30% of patients consistently stayed on hormone therapy for 5 years after a lumpectomy
A large U.S. study found that many people with early-stage, hormone receptor-positive breast cancer don’t stay on hormone therapy consistently for the full five years after a lumpectomy. Among more than 17,000 patients, only 28% had their medication available often enough to meet the study’s standard adherence level throughout all five years. This matters because some people with lower-risk breast cancer may be able to skip radiation after a lumpectomy, but hormone therapy is an important part of this approach and is intended to be taken for several years to help lower the risk of the cancer returning. People who didn’t receive radiation were more likely to have significant gaps in their hormone therapy, but more research is needed to understand what is causing those gaps.
For patients considering skipping radiation, these findings highlight the importance of discussing whether long-term hormone therapy is a treatment you can realistically continue, along with the benefits and side effects of each approach.
Disclaimer: The information provided in this article is for informational purposes only and is not intended to be a substitute for professional medical advice, diagnosis, or treatment. Outcomes4Me is not acting as your caregiver, and any suggestions or guidance offered should not replace the advice of your healthcare provider or qualified medical professional. Always seek the guidance of your physician or other qualified health provider with any questions you may have regarding a medical condition.
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