My psa is between 8 and 9 but biopsies are negative - why?

That is what it's... Clinical significance of psa can widely vary among individual men: high psa doesn't mean we always can find prostate cancer in biopsy; low psa doesn't guarantee no prostate cancer either. More detail on psa-related subjects? To http://formefirst.Com/freeinfoprostate.Html and http://formefirst.Com/newauapsa.Html .
Possible. Either you have a case of prostatitis / BPH only or your biopsies have missed the target (not common). Sometimes due to very small areas of cancer in the prostate a diagnosis can be hard to make.