Poor Mr Langdon. It certainly was a long and drawn-out death. Eighteen years. Doesn’t sound like he was on his deathbed the whole time though.
You can look at it from the angle where he could have died earlier from falling under a cart or being eaten by a shark or some other unexpected end that can befall any of us at any time, and say he had a pretty good life anyway.
Eighteen extra years of life, even if he was slowly losing his arm with each bit of surgery, is better than being a sharks dinner or falling down a mine shaft. I wonder what the recurring lump actually was?