My situation is different, but I understand a bit of that. Because the prostate cancer compressed my spine and permanently damaged the nerves, I have weird pains (or lack of sensation) all over, and find it almost impossible to know what's normal and what's not, so I probably wouldn't recognise pain from a new tumour if it started growing.

That said, with prostate cancer we have the benefit of PSA as a strong marker (especially with the ultrasensitive test), so when that's combined with periodic medical imaging and other blood work I can be reasonably confident (never 100%, of course) that my cancer is staying dormant and not progressing yet.

For pain management, I tried many things without success, but eventually ended up on Pregabalin, which is very effective for reducing nerve pain like mine; however, it also reduced my already-damaged sensation in the area where I'd been paralysed, so with my doctor's consent, I titrated off it gradually (there were a few false starts, but I finally stopped completely after about 18 months). In the end, I preferred feeling my legs, feet, and abdomen a little more to being pain-free and numb, but that's a very personal choice, and everyone will respond differently. I still take a Tylenol to help me sleep when the pain is elevated, but most nights I manage without.