Hello Charlotte1971, and a warm welcome. I am sorry to hear of your dads diagnosis I too have prostate cancer. Unfortunately one of the side effects of treatment can be incontinence and it can get worse before it starts to improve, It is possible with kegel exercises also called pelvic floor exercises, and bladder retraining which just means trying to hold on a little when you need to pee and gradually increasing the time. "Your cancer nurse specialist should help", and the right food and drink also helps, so no caffeine, fizzy drinks or alcohol, spicy or acidic foods, your dad may find having his last drink 3 hour before bedtime helps, but please don't reduce the amount he drinks he needs at least 4 and preferably 5 pints a day, it  is very important during treatment. Charlotte radiotherapy can sometimes aggravate the problem, i also know how unpleasant being incontinent is but it is a small price to pay for a cure, good luck with treatment, take bare, Eddie