What is proton radiation, and is it particularly good for some types of cancer?

Pediatric cases: Protons have a unique feature that allows the majority of its dose to be delivered within a very small range. So it can be useful if you have a tumor close to a critical target such as the spinal cord and you want to give as much dose to the tumor but to have the dose "stop" before it reaches the spinal cord. Protons can be particularly helpful in certain pediatric cases.

Heavy particles.: Protons is the positive charged particle in an atom. It takes very expensive machines to be able to give this therapy and in general this therapy is available in research centers. Over my 20 years it has been shown to be very beneficial but not practical because of limited availability. There are alternative forms of radiation that is still the standard of care.