Jeff is right these 4k snd PSE assist in the decision making process of going forward with a biopsy which you have done multiple times and recently. I believe the PSE might have a little more accuracy than 4K and determine risk a little different Possibly repeat the 4k to confirm previous one or supplement with the PSE. If the PSE comes back similar high risk, i would say something is being missed. Then move to another MpMRI since that has been two years. A lot can change in two years and even your recent saturation biopsies can miss things. It could be a new MRI could identify something in your case for just a targeted biopsy , not any additional random cores. I think with your PSA and 4K and a two year old MRI regardless of the last biopsy should justify another MRI especially if the PSE results corroborate your 4k