I had one HDR procedure as a "boost" to 25 daily IMRT sessions and six months Orovyx ADT. Overall virtually no long term side effects (pain, bleeding, incontinence, impotence, etc.). Just hit nine months post treatment mark and PSA down from 7 to .1. I am a big believer in HDR but I don't know the efficacy of using it as a monothereapy...my HDR was a boost on top of other treatments