As far as testosterone goes, while we talk about it "feeding" prostrate cancer, I don't think that's quite accurate; what it does is just throw the switch to start the cancer cells reproducing.

Just as a toddler can throw a light switch as easily as a 300 lb weight lifter (and the light doesn't shine any brighter because the weight-lifter is stronger), it probably takes only a relatively small amount of testosterone to start the prostate cancer cells reproducing.

Eventually, some (not all) cancer cells figure out how to switch themselves on, though ARSIs like the -lutamides can delay that for many years in some cases.