What are your thoughts on a 59 year old whose PSA has fluctuated between 1.8 and 3.1 over a nine year period, 3.1 was the last reading, DRE normal, had a MRI of the prostate which was normal, and lastly had the pca3 done which came back at 34. Now urologist wants to do a biopsy. What are the chances of prostate cancer? Thanks for your help in advance!