Shane,
Your weight is frightening. It seems you must not have a PEG.

Are you being treated at a Cancer Center by a multidisciplinary team?

I have had weekly appointments with Dietitians since surgery and their job was to fatten me up and get me ready for using the PEG and formula.

Post surgery, I was immediately gaining weight.

This is likely to only get a lot worse and at your weight you really need to get pro-active with your medical team.

I would ask them if you might still be able to get a PEG and if so do it this week. You will regret getting PEG for a few days, but after that really be glad you did.