Malcolm stopped in at Cheers one very cold day for a drink. He took a seat at one of the tables, and was waited on by Diane. He accepted her recommendation of hot buttered rum, and told her he'd just had one of the worst days of his life. Diane tried to pick him up with a silly joke, but when Malcolm revealed he was just given six months to live, she apologized for being factitious. Diane asked Sam to go talk to him. Although his fate is left unrevealed after this, it is presumable he died.