I don't have any info on this, but I would suspect that any info someone might have would be held under strict confidentiality.... POW's in many cases are kept in solitary situations and even if not, the prisoner mentality would probably be more of US against THEM and working to keep each other up and as strong as possible .... so rapes would generally be by their captors ... but the military, even at the best of times can be a bit "homophobic" and would want to shelter this info from public knowledge.

I do know that during WW II in the German POW camps the standard was much higher in how they treated the POWs then what was the case in the camps holding civilians.

Know that's not what you were looking for either, sorry!