08/19/2008 at 11:00 AM EDT
It was a happy – and healthy – 56th birthday Monday for Patrick Swayze, who celebrated on the Chicago set of his A&E series, The Beast
The Dirty Dancing
actor, who revealed in March
that he is battling pancreatic cancer, filmed scenes in Chicago's Millenium Park beginning early Monday morning and throughout the day, surrounded by fans who came out to wish him a happy birthday.
When lunchtime rolled around, Swayze and wife Lisa Niemi enjoyed a birthday lunch at his trailer. The crew, which had decorated his trailer for the occasion, presented him with a birthday cake.
But that wasn't the only surprise of the day. When Swayze returned to the set after lunch, he was greeted by crew members wearing matching black shirts with white letters saying "Crazy for Swayze," with a picture of the actor.
The crew surrounded him and sang "Happy Birthday" to the actor, who was all smiles.
The actor has remained in good spirits during his cancer treatment. Last month, he told photographers and fans
, "I'm a miracle, dude ... I don't know why."
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