Unfortunately, Rick, I did not learn a lot from today's meeting that I didn't already know. The opinion is that pre-existing cancers, save for bladder cancer, are unlikely to be a significant cause of prostate cancer. Only bladder cancer is of the same pathological type.
The most aggressive form of prostate cancer is linked to family history (often hitting younger men). Otherwise it appears not to be caused by "bad behaviour": smoking, drinking, drugs, sex. There is a strong racial link with blacks being hit the worst while Asians get off realtively lightly.
Tomato is the only known food type that helps to stem postate cancer.
This consultant is very supportive of PSA testing albeit that it doesn't have universal popularity in the medical profession.
I did Google and read a number of papers myself. The findings of various studies are far from consistent. What does you oncologist think?