Tim-
as a physician and son of someone with prostate ca, your dad has many options ahead of him and early detection nearly always results in excellent outcomes. It is best to find a urologist who is board certified and if in doubt about his/her treatment plan, always seek a 2nd opinion from another unbiased physician. Treatment and monitoring regimens are rapidly evolving and there are many differing opinions on treatment scenarios out there.
There is an old saying in medical school...."any man who lives long enough will develop prostate cancer in his lifetime" It is common and treatable. Best to you and your family...