Is there any evidence that demonstrates an increase in rectal or bladder toxicity with protons for prostate cancer compared to IMRT?  

This is a great and controversial question. I recently contributed to a review that tried to summarize the current studies to date looking at this question. As you know, there are no completed phase 3 trials comparing protons to photons in this space, and we eagerly await results from the PARTIQoL t...

It is unclear if proton therapy increases or reduces the risk for rectal or bladder toxicity when compared to IMRT. There are two prospective clinical trials including the aforementioned PARTiQol and COMPPARE trial that may help to answer this question in the future. The dosimetric benefit of proton...