Bobby here is one take on your question:

http://drhyman.com/blog/2013/07/26/c...ostate-cancer/

It seems that the study was flawed, according to this doc. Also he gives several reasons why it would be odd if it did cause prostrate cancer

Still I am curious now because I consume 5+ g of fish oil and 2 krill oil capsules a day. I have had some issues with the prostate and antihistamines.