A new article in this month’s issue of The ASCO Post addresses the need for concrete evidence that proton beam radiation therapy (PBRT) is actually “better” than modern forms of photon-based external beam radiation therapy (EBRT) in the management of prostate cancer (and other forms of cancer).
The article, by Theodore Lawrence, who is professor and chairman of the Department of Radiation Oncology at the University of Michigan, will likely infuriate some members of the proton beam brotherhood. For those of us who like good data to support our faith, it seems like a very rational commentary on a very complex topic.
Dr. Lawrence suggests that — if this is really the case — it ought to be relatively easy for the proton beam radiation facilities to develop data to show that either
- “Protons can be used to safely deliver a higher dose of radiation than photons to … the prostate “
- Protons can be used to better protect the rectum and bladder than photons at the same tumor dose as delivered by modern IMRT.
He notes that if such evidence is forthcoming, then the onus will be clearly placed on the entire radiation oncology community to conduct the randomized clinical trial(s) needed to prove that PBRT is a superior form of clinical treatment compared to photon-based therapy.
As Dr. Lawrence also observes, this is not the first time that the radiation oncology community has had to deal with a controversy like this. An analogous controversy back in the 1980s and early 1990s required radiation oncologists to “prove” that three-diemsional treatment planning produced better outcomes for patients than the earlier two-dimensional treatment planning. The radiation oncology community was able to overcome that challenge, so why not the current one?
The “New” Prostate Cancer InfoLink believes that the proton beam advocacy community needs to actually be able to prove its case. Whatever one’s beliefs, there are no good data to support the supposed clinical benefits of PBRT compared to IMRT today. The most basic principles of evidence-based medicine and patient-centered outcomes research require us to insist on data that can justify the use of PBRT as an improvement over modern EBRT — as opposed to just an expensive alternative with similar outcomes.