Won't eat, what can we give him

[TheMissMarple]

My parents wonderful dog is very poorly with thyroid cancer (removed and no signs it spread) and possible pancreatitis and prostrate problems. Hes on various medicines which don't seem to do anything. He's starving himself to death as he just won't eat and is sick when he does. He's going in for more surgery this week at vets firm recommendation to explore his pancreas however he's becoming skin and bone, doesn't want to go for walks and is clearly feeling lousy. We've tried everything we can think of to encourage him to eat and are more than desperate now. Sorry it this is a little rambling, it isn't a good time for us. Any suggestions please?

[MuttsNutts]

Oh I am so very sorry

R.I.P. handsome boy