Boyle, who died Tuesday night, had heart disease and multiple myeloma, a type of cancer of the plasma cells, his publicist Jennifer Plante said.
Despite his "Raymond" character Frank Barone, "Peter is very intellectual," his wife, Loraine, told People magazine in 1999. "He can talk about anything from philosophy to politics to history. With Frank, his character, you get the feeling that he's mainly interested in the next slice of pizza."
Born Oct. 18, 1935, in Northtown, Pa., he studied acting at age 25 after three years as a Christian Brothers monk.
Often playing a thug and gangster in movies, Boyle was also the bumbling monster in Mel Brooks' 1974 spoof "Young Frankenstein." On the "Frankenstein" set he met journalist Loraine Alterman, whom he married in 1977, with their mutual friend John Lennon as best man.
Boyle was nominated for an Emmy for his "Raymond" role.
Besides his wife, he is survived by daughters Lucy and Amy.