high-grade PIN frequency of follow up

 I am a healthy 71 year old male, very active and still working as a political consultant. 

MY PSA level increased over the past 16 months from 2.1 to 3.2 and as a conquence my new urologist suggested a bioposy even though his digital rectal exam showed a healhy prostate.

The bioposy , ( 12 samples taken) ,showed showed 4 areas of high-grade PIN.

My urologist suggested that a follow-up biopsy be done in three months.

I emailed my previous uruoligist (Dr Catalona who developed the PSA studies program at Washington U. in St. Louis some 10 years ago), and asked his opinion on the necessity of so early a follow-up bioposy when high-grade pin is discovered.

His response was that in general he recommends a follow up bioposy, when high-grade PIN is found, a year following the finding, and then quarterly PSA testing during the year.

When I shared Catalonas recommendation with my current uruologist , he said that PSA levels no longer have any diagonistic benifit once high-grade PIN is discovered and insists the proper follow up biopsy should be done in three months.

 Can someone give me their experience after a finding of high-grade PIN.

Many Thanks,

Martin Flannery