GRASS VALLEY, Calif. -- Gibson, the world's tallest dog, is suffering from bone cancer, Sacramento television station KCRA reported.

The Great Dane, which stands more than 7 feet tall, has appeared on "The Oprah Winfrey Show."

Earlier this week, veterinarians had to amputate Gibson's right front leg.

Gibson's owner said he's coming home later this week and she expects him to be in the limelight in just a couple of months.