Proton, X-ray Radiation Therapy Both Offer Good Quality of Life

Some people feel proton therapy is more technologically advanced than traditional X-ray radiation therapy, but when it comes to how people with non-metastatic breast cancer look and feel after the treatments, the two appear equal.

Results from the RadComp study were presented at the 2025 American Society for Radiation Oncology Annual Meeting.

“Radiation oncologists have debated whether photon [X-ray] or proton therapy is the better choice for treating breast cancer, and there has been little high-quality evidence to guide those decisions,” presenting author Shannon MacDonald, MD, FASTRO, said during a media briefing on the results. MacDonald is director of the Southwest Florida Proton Center. For the current study, she and her colleagues compared how people felt after proton therapy versus X-ray radiation therapy.

A newer type of radiation therapy, proton therapy is thought to be more precise than traditional X-ray radiation. X-rays hit the treatment site, but can continue through the body, possibly affecting tissues in their path. Because the breasts are close to the heart and lungs, these organs may receive some radiation, which can lead to other health problems. Newer ways to deliver radiation for breast cancer, including receiving radiation in a facedown position or while holding your breath, help minimize the amount of radiation that hits healthy tissue. Unlike X-rays, once protons hit the treatment area, they stop. This may reduce the risk of the radiation hitting other tissues and might make side effects less severe.

The study included more than 1,200 people with non-metastatic breast cancer. Half were randomly assigned to receive traditional X-ray radiation therapy and the other half received proton therapy. About 70% of the people had a mastectomy, and everyone in the study received radiation to the internal mammary lymph nodes, the nodes deep in the breast tissue along the breast bone.

All the people filled out questionnaires before radiation treatment, right after treatment ended, and again, one and six months later. The questionnaires asked about the people’s physical and emotional well-being. This included questions on side effects, such as pain and shortness of breath, and satisfaction with cosmetic outcomes.

Both groups reported excellent well-being and satisfaction with treatment results.

“Patients should feel reassured that they can receive high-quality care with either [X-ray] or proton therapy,” MacDonald said. “More than a thousand patients in our trial have now shown that, with contemporary treatments, we can deliver curative radiation in a way that preserves multiple aspects of quality of life.”

The researchers plan to follow the two groups for at least 10 years, so they can see if there are differences in recurrence rates (the cancer coming back) or long-term side effects between the two types of radiation.