Nels has good advice regarding learning the technical differences between the two different types of radiation. The are many but the most important difference which isn’t always an advantage is that Proton can be more targeted than IMRT, which over the years of radiologists learning to use it better can be mapped to a specific area very closely. This is why it’s the go to in brain radiation where precise application is really critical.
This is all about not damaging other areas with radiation that are not part of your needed treatment. Some of those like salivary glands, certain nerve bundles in the carotid notch of your neck that control your bodies ability to sense blood pressure, and others are important. Many times the radiation cannot be mapped around them to get to where it needs to go. So this can be very much about where your tumor is and if it is very defined and focal, or if it is more diffused.
You did say something that I’d like you to clarify. That was that you have perineural invasion. That makes me think that your cancer is ACC or MEC, not SCC The most common type. The first two are much less common and can be harder to irradicate. Also if the disease extends from the main tumor down some nerve pathways, will they go after those surgically or try and eliminate them with radiation. This is a question that might favor one radiation type over another. Here I would go with doctors recommendations because this is an important difference in needed treatments.
In many oral cancers, especially squamous cell carcinoma SCC, we know that the cancer can be very diffuse. So there is often a well defined focal edge to it, but around the tumor within a centimeter or more, there are reside cells which do not read as malignant but dysplastic. Dysplasia is a state of not cancerous, but not normal, the cells are in a state that leans towards becoming cancer, but are only partly transformed. This is called field cancerization. Whether they continue transformation is always an unknown. This makes surgery only as a solution impossible, because it great increases the area to be removed, and ultimate morbidity to the patient. But knowing that is the case, they will map the radiation in a lesser strength or duration to cover those areas as well. (IMRT for instance can be “tuned” and mapped in several ways. Intensity, spread, and duration, being the most useful. So think a bullet shape or a shotgun pattern. They can hit the main tumor with a higher intensity and duration, and paint the surrounding area with less. This is the true advantage to IMRT over the previous XMRT once radiologists learned to use this tool,) This is why in surgical only removal, even with a clean margin, some patients have recurrences a year or two later. Those cells become fully malignant - and it is customary to prevent that by doing some radiation to that area to eliminate that possibility after surgery. Those are never actually recurrences, technically they are incomplete primary treatment.
The last issue will be insurance. Proton is significantly more expensive, this is because the machine is significantly more expensive and hospitals charge more to recoup that investment. Insurance companies often balk at paying for proton if they believe IMRT will accomplish the same end results. This is an argument that happens a lot, it it must be circumvented by the doctor making the case for a clinical advantage.
Last edited by Brian Hill; 05-06-2023 08:17 AM.