After having prostate cancer four years ago and now suffering from an inflamed and enlarged prostate causing urinary blockage, my urologist thinks i should give up cycling, but thats my favourite activity i share with my wife. what should i do?

You should follow your doctor's advice and talk to your wife about the necessity of changing your leisure activity. Fast walking or hiking together can be your alternative.

make sure that the diagnosis of inflamed and enlarged prostate is correct for if you had radiation and or hormonal treatment it shrinks the prostate size - almost always- so a second opinion. In the meantime get rid of the banana seay and try a more cushioned bicycle seat. Good luck