Dr. Jimenez on the Management of Radiation Toxicities in Breast Cancer

Rachel Jimenez, MD, the chair of Quality and Safety in the Department of Radiation Oncology at Massachusetts General Hospital, discusses the management of toxicities associated with radiotherapy for patients with breast cancer.

During the 2022 San Antonio Breast Cancer Symposium, Jimenez presented on the current state of radiotherapy in breast cancer, including ways to reduce toxicities and novel options for administering radiation.

When patients with breast cancer require radiotherapy, there are concerns regarding toxicity to surrounding tissue, including muscles, ribs, heart, and lungs. The shoulder, thyroid, and esophagus can also be affected, depending on the area being treated with radiation. To understand ways to reduce toxicity to surrounding tissue for these patients, clinicians must examine ways this tissue can receive less radiation exposure, no radiation exposure, or less detrimental radiation exposure, Jimenez says.

Novel technologies could help improve the therapeutic ratio of radiation for patients with breast cancer while mitigating toxicities to normal tissue. Proton therapy has the potential to help spare normal tissue, Jimenez says. In proton therapy, a proton dose is deposited in the form of a Bragg peak, with a sharp fall-off distal to the peak of the dose, reducing the exit dose beyond the distal tumor edge relative to the beam approach to decrease low-dose radiation to normal tissue.

Proton therapy is a form of radiation that can be targeted in a specific way to prevent low-dose radiation from affecting normal tissue that is not intended for exposure to radiation. For example, when women receive radiation to the left side of their body, proton therapy could help spare the heart from exposure to radiation.

Ongoing clinical trials are exploring proton therapy in patients with breast cancer, particularly for patients with advanced breast cancer who may be at risk of having more cardiac exposure to radiation, Jimenez concludes.