Open Mics 10-4-23 - Proton vs Photon Radiation

Dr. Steve Stites, chief medical officer, The University of Kansas Health System

We've talked a lot about proton beam therapy on this show because it's new to our Cancer Center and it's relatively new to the field of cancer and medical oncology and radiation oncology.
It is a different form of radiation for certain kinds of cancer and it may be superior for things like some types of head and neck tumors.
But for breast cancer, the more traditional photon radiation is still the standard of care.
Science doesn’t always give you your answer because the science is so dynamic. We have to keep studying and keep learning so we can live our best lives.


Dr. Kenny Guida, D.M.P., assistant director, proton physics, The University of Kansas Cancer Center

With proton therapy, we're able to focus a really tight beam in a specific area. We want to put these spots within the tumor cells themselves. The have a finite range – the Bragg peak.
They work by the energy they have, not necessarily the radiation they have, so we can strangle the energy and we can assume that we put all the spots in the Bragg peaks, align them within our target, and we can spare all the normal tissue around it and behind it as well.
Photons still work in a similar matter -- they're going to travel through a tissue and some of their energy on some electrons, maybe some neutrons and photons that they're passing through, and that will depart energy within the tissue itself.
But the problem is with photons is that they keep traveling. Whereas protons have a range based on how much energy they have.
Dr. Shane Stecklein, M.D., Ph.D., radiation oncologist, The University of Kansas Cancer Center

Proton therapy can help deliver radiation more effectively to the area where it needs to go, so it doesn’t radiate to vital areas like the lung or heart when treating breast cancer patients.
When it comes to what types of breast cancer patients are most suitable for proton therapy, we know there are multiple types of breast cancer and biologically they behave differently.
From a radiation perspective, it's really more about anatomy in the areas that we need to treat. So we treat a triple negative breast cancer very similar to how we treat a hormone positive breast cancer in terms of the regions we treat.
One percent of breast cancers are in men. Historically, from a surgical perspective, they were all treated with mastectomy. That's not the case anymore -- men can be eligible for lumpectomy and much smaller surgery and we really treat them much the same way that we treat women.