Hi and welcome,
my treatment pathway is a little different to yours (see my profile), but I recently had 6 rounds of Docetaxel chemo starting in August '24 and finishing in December. This was my second bout of Docetaxel, after my initial treatment back in 2019. My consultant suggested the second bout to try and slow the progress of some mets in my liver, bones and lymph nodes.
The chemo did keep my PSA suppressed during the 6 cycles of treatment, and scans showed it shrank the tumours on my liver and elsewhere, which is good. While I found the first 4 cycles were fine and relatively easy to tolerate, the final 2 cycles of chemo were really brutal, I was bedbound for days after both. At that point I stopped treatment (my consultant suggested up to 10 cycles were possible, if I was tolerating it OK).
My PSA is now rising rapidly like yours, but I'm very much focusing on QoL. I have been offered further chemo using a different drug (Cabazitaxel) but I'd have to be convinced it would offer a real longevity / survival benefit. I'd rather be reasonably well and doing what I enjoy, than spending days either in bed or draped over the sick bucket.
Having said all the above, you could start the chemo and see how you go on for 2 or 3 rounds. It will have some effect in slowing disease progression. If you're managing it OK, carry on; if it's making you ill, you can always stop.
Don't hesitate to ask if you've questions about the chemo, and best of luck with whatever you decide to do.
Cheers, Craig