I don't have answers for you, but I understand your fears. Because the prostate-cancer metastasis to my spine caused severe nerve damage, I have either limited sensation or semi-random phantom sensations in much of my body below the ribs.

I can walk again now and have enough sensation to get by, but when the doctors ask me if there's pain, I have to say "honestly, I have no idea." It's like trying to understand a call over a badly-broken telephone line.