My prostate was not enlarged, my PSA at the end was 4.2. Only because my doctor was overly cautious about the slope of the PSA rise did he send me for an MRI starting the diagnosis. It remains to be seen if it escaped containment.
The point here is, I don’t think enlargement and cancer are that intertwined. Cancer happens for any number of reasons, pinning hope that it can be staved off by diet and vitamins seems to ignore tons of other environmental factors.
I'm also glad you found a good doctor, the first I found did no checks at all. Told me I'm too young to have any problems (I'm definitely not) and sent me away with some herbal medicine and all that stress I mentioned. The second doctor I found was thorough and reassuring, and shocked by the behaviour of the first.