Hi Bob,
Hearty congratulations on that negative biopsy, especially as it is the third negative one!
Are you aware that prostatitis can throw free PSA way off? That could explain why you have a low free PSA but no PC found in the biopsy. If you have the PC bible, "A Primer on Prostate Cancer - The Empowered Patient's Guide," turn to page 38: "... prostatitis can result in low free PSA percentages that make laboratory distinction from PC treacherous...."
I would bet you are fine, but for peace of mind you might have a PCA3Plus test run. It's results are especially useful for men with some indicators of PC but one or more negative biopsies.
Another tactic would be to go on either of the drugs finasteride or
Avodart. Both were approved as BPH drugs, but finasteride has been proven to have anti-PC activity as well, and recent studies have shown that it is safe (some docs still haven't caught on).
Avodart very likely has anti-PC activity, probably even better than that of finasteride, but trial results aren't in yet. Your PSA should drop to half it's value on finasteride if you have no cancer, but any prostatitis would still complicate the picture I think.
Take care,
Jim