Actor Ryan O'Neal was diagnosed with prostate cancer but he is optimistic and expects to make full recovery.

O'Neal, 70, was "shocked and stunned by the news," according to a statement he released to CBS News.

"I have it under control," O'Neal told ABC's "Nightline."

"I wasn't prepared for it. I wasn't ready for it. But you never are," he told the show.

O'Neal's most recent role is on the TV series "Bones."

Tags: Ryan ONeal