Note to family members — this post doesn’t contain any information that wasn’t in my last email message.
We saw Dr P on Monday, to get the unwelcome news that the PSA was up at the last test. However, the current level is 0.3 — still obviously less than 1. When we found this out, we were somewhat daunted. Our feeling was “a rise is a rise”. The consult didn’t allow us time to process the information or ask what it meant. However, on the advice of Dr P’s PA, I sent him an email with some questions. He rang me back the same day and I learned a lot more about it. The new information:
- the increase I had had was not a rise in clinical terms.
- He would be worried about an increase of a much bigger trajectory, e.g. if it was
measured in whole numbers (integers), and doubling in 4 weeks. So, for example, if I had a PSA of 5.0 and it went up to 10.0.
- Increases in fractions of 1.0 aren’t really accurate anyway. (This information is given in a disclaimer on printout from the path company — a copy of which Phillip gave me on the day.) So, while one may worry about going from 0.09 to 0.3 — an increase of 0.21, which is more than double the first score — it’s a mistake to read too much into that increase. At that quantum it’s not really meaningful.
- He doesn’t look at the number itself, but at the velocity of the increase. (This goes back to #2 above.) A steep increase is most undesirable. But if it just grumbles away, as he put it, and increases gradually, that’s not alarming. Scores can move around, particularly under 1.0.
- One of the things he teaches his students is not just to look at the PSA, but look at the whole person. Do they feel (and look) well and healthy? On that basis, I am doing very well.
- One of the questions I had sent him was whether I would need to move to another treatment (e.g. another round of chemo). He doesn’t think that will be necessary for some time (see below). The longer we can delay my moving to a second-line treatment, the longer I’ll live!
- These are the answers he gave me to the questions I had sent him:
Does he believe the cancer is progressing? No.
Is he worried at the last increase? No.
Is he expecting that I may need to move to a different treatment? Possibly, around the end of this year.
- He reminded me the treatment I am having presently (androgen deprivation) is Plan A. It has an expected maximum life of about 24 months. (I started it around Christmas, 2018. I can’t recall exactly, as it started as adjunct treatment with the chemo. The latter definitely finished on Boxing Day, 2018 — that I do remember!) Beyond Plan A, however, he has Plans B, C, D and E.
So the whole exercise was quite reassuring. He hadn’t realised we were worried — to be fair, we were wearing masks, which may have made it more difficult to read our expressions. Anyway, I will be talking to him in about 5 weeks, after the next blood test.
There is a lot of ambiguity around PSA. As I commented before, people look for certainty, and want a simple test to see whether they are doing OK or not. There is a temptation to simplify: low PSA is good, high PSA is bad. As you can see above, it is a lot more nuanced than that. Dr P thinks PSA is a really useful way to see whether someone who has been pronounced cancer-free has suddenly relapsed. It is a less useful measure for someone like me in whom the disease is continuing.
However, I think medicos are partly responsible for this fetishising of the score. For the first half dozen or so consults this year, Phillip was very enthusiastic about my having PSA that was undetectable. He seemed different in the last consult, and I read a fair amount into him being much less effusive than usual. I can see I drew the wrong inferences, but then, I’m not an oncologist.
I believe situations like this arise because experts find it really difficult to remember what life was like before they became experts. Their knowledge gives them an incredibly rich context in which to interpret things. Can they meaningfully ask themselves the question “How would I interpret this if I didn’t know what I know?”. It’s an almost impossible task. Also, people join the dots in an attempt to find a “take-out” message.
My take-out from this? If in doubt, ask questions. There’s no statute of limitations — you can ask questions that occur to you after the consult. (My beloved prodded me to do this, and it was the right thing to do.)