There is a lot of correlation between low testosterone levels and prostate cancer, rather than high testosterone levels. Some studies have indicated that men with low testosterone levels are more likely to have higher grade cancers as well.
There is no established causation, but correlations have been found multiple times:
www.medscape.com/viewarticle/540617_2www.lef.org/magazine/2008/12/destroying-the-myth-about-testosterone-replacement-prostate-cancer/page-01www.natureworldnews.com/articles/6888/20140505/low-testosterone-levels-marker-aggressive-prostate-cancer.htmbreakthroughs.cityofhope.org/testosterone-prostate-cancer-riskwww.webmd.com/men/news/20071127/low-testosterone-early-deathAnd, yes, I had low T before my diagnosis, took TRT for a year, had my diagnosis and treatment, and then resumed TRT 6 months after my RALP. I will admit I'm not an unbiased observer on this topic.