I had 40 sessions pelvic IMRT 80gy over a year ago along with Orgovyx and Zytiga / Prednisone which I'm still taking for about another six months. I didn't experience any burning sensation, however urinary frequency and urgency began about halfway through the radiation treatments. This continued for several months afterwards and caused me considerable stress especially the urgency when I was away from home. It has mostly abated at this point in time. I still get up twice a night to pee sometimes only once if I don't drink anything a few hours before retiring. Anyhow, my bet is with more time your situation should improve. I'm guessing, but you're burning sensation is likely due to radiation rather than ADT or ARPI. Dysuria can happen but I think rarely from the drugs? What type and how many radiation treatments did you have. I believe the shorter courses are more likely to involve radiation cystitis.