I'm so sorry to hear about that. I also had pain and trouble closing my right fingers into a fist, about six months in. I don't know if it was the Erleada, early arthritis, or something else.

It was especially upsetting for me because I had played classical guitar before my cancer diagnosis and hospitalisation, and I didn't want to lose that on top of everything else.

I worked hand exercises into the physiotherapy I was already doing, including squeezing foam balls and then exercise grips. I still have some issues, but in my case the daily exercises eventually dealt with most of the pain and stiffness, and let me play guitar again (including at my daughter's wedding).

As always, your mileage may vary.