ALA and prostate cancer

Epidemiological studies link alpha-linolenic acid to Diseases like prostate cancer. Again: is it the processing or ALA itself? That question is usually not raised in such papers. Cooking is very complex chemistry. I suspect that this ALA is mainly from canola not from leaves. So we have to dig in the process of canola oil production/processing/filtering and other transformations occurring before people eat it. Don't forget that usual pans on gas fires or electric heating are at very high temperatures and people tend to tune the power at max in order to get "fast" food...