"He is a strong man, a fighter," DeVito said of his soon-to-be 66-year-old friend.
"Michael is very brave, as you all know. He is giving his best shot and really optimistic about it and I'm sure he is going to kick it. I really feel that way."
DeVito, who most recently worked alongside Douglas in Solitary Man, as well as War of the Roses, Romancing the Stone and appearing in One Who Over the Cuckoo's Nest, which Douglas produced, said that the support of friends and family as well as well wishes from fans, is helping the actor cope with his battle.
"He's going to do really good. He's going to get through this with everybody's help. Everybody out there is loving him and send him all the love in the world.
"Good man," he said. "Good friend."
Get everything we have on Michael Douglas' cancer battle.