Thanks for that. This helps confirm what I've been piecing together: from my understanding, the extra epigenetic test (the "E" in PSE) isn't useful if your PSA is normal/low/undetectable; however, if your PSA is high, adding the "E" can help you determine more accurately how much it matters.

So as long as my PSA remains < 0.01, PSE holds no value for me; but if it were to start climbing to (say) 10, the extra epigenetic test would help me know whether the cancer was spreading quickly yet and choose an appropriate treatment course.

Does that sound right?