Most of these studies are bogus, and this one is no exception.
First of all, they didn’t say how old the men were in this study. Most elderly men get prostate cancer, it’s just that it’s slow-growing and something else will take them away first.
Second, I didn’t see anywhere if they reported this in terms of relative or absolute risk. If 6 men out of 10,000 were the ones with high omega-3 levels and got cancer but only 2 men with low levels got cancer, then what does that mean? Not much.
There is so much bad science out there that you really can’t believe much of anything. This group analyzes medical stories in the news and points out the errors: http://www.healthnewsreview.org/
If it weren't for bad science, we wouldn't have any science at all. :0\
So much of "scientific research" is done in a vacuum. They do test groups by adding a single item such as Omega 3 and report their findings never taking into consideration that the subject may well be deficient in a variety of nutrients.