Well, with the jump in my PSA to 0.08 ng/ml that I reported a few days ago, I’ve been poring over some literature on the debate between the standard PSA test that’s been used for years and the newer ultrasensitve PSA test (which I’ll abbreviate uPSA) that my provider switched to in March 2015. Let’s review:
- In January 2015 I had my last undetectable reading (<0.03 ng/ml) using the standard PSA assay.
- My provider switched to the uPSA assay in March 2015.
- My September 2015 uPSA reading came back at 0.05 ng/ml, sending me into full panic mode. Given the accuracy of the standard PSA test of +/- 0.03 ng/ml, it, too, should have been able to pick up the 0.05 ng/ml reading in September if it had been used.
- We retested in December 2015 and my uPSA was 0.04 ng/ml. I would attribute the change from 0.05 to 0.04 to the daily variations that so many talk about and consider that to be insignificant. Still, the standard PSA test could have picked up the 0.04 reading had it been used.
- And now in April 2016, my uPSA was 0.08 ng/ml.
Those against using the uPSA argue that we’re simply measuring noise and that anything under 0.1 ng/ml should not be used as a decision point to start salvage therapy. They also call into question the accuracy of PSA doubling times using the uPSA test given that it may be measuring more noise than actual changes.
Those embracing the new uPSA test argue that initial, small-scale studies show that uPSA can be a predictor of recurrence with readings as low as 0.03 ng/ml, and that it allows for earlier intervention with salvage therapy. More large-scale research is needed to confirm these early findings.
Some of the literature written against the use of uPSA goes back to 2000. Technology advances in sixteen years, and that would be my question to those opposed to the uPSA. At one point in time, I’m sure that doctors and scientists scoffed at the standard PSA test as being a newfangled, meaningless test that wouldn’t provide doctors or patients with actionable information, but it became widely accepted.
All I know and care about as a layperson is that there is upward movement on my PSA when there had been no movement for four years. Even if it’s just noise, 0.08 is getting awfully close to 0.1 and is halfway to 0.2—and it took just seven months for this to happen. That scares the crap out of me.
And, if I am destined to go down this path of recurrence, don’t even get me started on the whole conflicting and confusing guidance on salvage radiation and hormone therapy! I’ll save those discussions for future posts.
When you’re dealing with cancer, you really don’t want to wish for days to pass quickly, except when you’re waiting for test results and doctor appointments. April 19th can’t come quickly enough right now.