[Update: Chris Andrews, who represents McKellen, denied that the actor has prostrate cancer]
"No, he does not have prostate cancer. … That was taken out of context and from an interview from years ago," Andrews told ABCNews.com.
Sir Ian McKellan, who plays Gandalf in 'The Hobbit' and Magneto in 'X-Men,' says he's been battling prostrate cancer for years and is being careful that it doesn't spread. So far, McKellan's cancer is "not life-threatening,' he says.
In an interview with U.K.'s Daily Mirror, McKellen says he has had prostrate cancer for six or seven years.
"When you have got it you monitor it and you have to be careful it doesn't spread. But if it is contained in the prostate it's no big deal," says the 73-year-old 'Hobbit' star.
McKellen first paid a visit to a doctor when he had to frequently use the restroom at night.
"Many, many men die from it but it's one of the cancers that is totally treatable so I have 'waitful watching.' I am examined regularly and it's just contained, it's not spreading. I've not had any treatment."
Prostate cancer occurs when cells in the prostate gland grow out of control. An estimated 80 percent of men who reach age 80 are diagnosed with the disease. Doctors recommend "watchful waiting" but if the prostrate cancer worsens, treatment options include surgery, chemotherapy, cryotherapy, hormonal therapy, and/or radiation.
McKellen admitted that he did gulp when he first heard the news of being diagnosed with prostrate cancer. He said that doctors told him he could have it "zapped" or "snipped" but that he wasn't a candidate for either.
For now, McKellen isn't ready to hang up his hat playing roles like Gandalf the Wizard from J.K. Tolkein's 'The Hobbit' and 'Lord of the Rings' series or super villain Magneto from the comic book series 'X-Men.'
"I have heard of people dying from prostate cancer, and they are the unlucky ones, the people who didn't know they had got it and it went on the rampage. But at my age if it is diagnosed it's not life-threatening."
McKellen will appear as Gandalf in 'The Hobbit: An Unexpected Journey,' which hits theaters on Dec. 14.