Thanks for the detailed explanation. That’s very helpful, and I think you’ve clarified something that can easily be misunderstood.

My concern was not really about whether a test that can measure down to 0.02 qualifies as an ultrasensitive PSA test—it clearly does. My concern was whether my particular assay reports PSA values below 0.02, such as 0.01 or 0.006, or simply reports anything below 0.02 as “undetectable.” In the latter case, potentially useful early information about a rising PSA trend could be masked.

I’ll try to check with my lab to find out exactly which PSA assay/methodology they use and what its lower reporting limit is. That should give me a better understanding of what my “<0.02” results actually tell me.

Thanks again for pointing this out. I appreciate the clarification.