@drcopp
The PSE test is a blood test that analyzes your blood for material that shows whether or not you have prostate cancer. It can be used when you have a higher PSA, but the MRI showed nothing. It can tell whether or not there really is prostate cancer in your system and that you need a biopsy.

Episwitch Is the company that makes the product and does the testing?

Here is a table that shows you the PSE test at the top compared to all the other others that were available a year ago. There are some newer tests.