He lost his ability to eat due to trismus, the growing tumor and surgery to remove it left a large hole in the side of his face, the cancer and radiation took his vision in his right eye.
From the edeneatseverything.com
The first sign is trismus, or lockjaw, and the facial spasms called risus sardonicus, followed by stiffness of the neck, difficulty in swallowing, and rigidity of pectoral and calf muscles.