I think that you are genetically prone to PCa and all the garbage the we eat, drink , smoke , breath finds it way into your body and gets you somewhere and somehow. As I stated in my case my cancer was there before I started cycling.
I would let you know that when you are scheduled to have a PSA test, do not ride your bike for 24 hrs prior becuase the stimualtion of the seat will raise your level. So will sex and don't let them take blood for the test after you have had a digital check, that will raise your PSA. Blood test first, then physical.
I asked my Doc what my PSA would be after my biopsie and he said in the thousands.
Cyling can exacerbate the condition of prostititus and as the above coments show saddle selection can greatly reduce that problem.
My cycling made it so I healed much faster than normal. I was out of bed in the hospital walking the halls 10 hours after surgery. I keep walking the next day and night in the halls. I had my MP3 player on listening to my tunes (M and M, Van Halen, Bob Wills, Dave Brubeck, Neil Young, Queen and Rigelleto) and was able to get home on morning 3. The doctors said in my follow ups that I was way ahead of the healing curve due to my cycling conditioning.
I pray for all of you have loved ones facing cancer. Prostate for me was the best cancer I could get because it was early detection and so far clean. My friends and relatives who face what Lance went through have it hard and those yellow wrist bands really mean alot.