Pianist Roger Williams battles pancreatic cancer

(CBS/AP) Legendary pianist Roger Williams is battling pancreatic cancer.

PICTURES: Stars standing up to cancer

Williams, also known as the "Pianist to the Presidents" for his numerous presidential performances, announced in an e-mail message last week to his friends that he started chemotherapy.

Williams, 86, was known for his 1995 recording of "Autumn Leaves," the only piano instrumental to reach No. 1 on the Billboard pop music chart. He is also famous for his hit "Born Free."

He said doctors told him they cannot remove the tumor until the chemotherapy shrinks it to an operable size.

Despite the fierce battle, Williams says he does not plan on canceling any upcoming concerts. He gave a sensational performance at his most recent venue on Sunday at Del Webb's Sun City retirement resort in Palm Desert, according to his personal assistant.

"What does it all mean? It means I'm in just one more fight -- the fight for my life," Williams wrote. "And this much I know, this old Navy boxing champion is going for broke. Just watch me!"