PHOTO EXCLUSIVE

Grass Valley, CA-He’s the most famous dog in America and the Guinness World Record holder for the world’s tallest dog, standing at an amazing 42.2 inches.  But now Gibson, the “Harlequin” Great Dane who won over a nation with his appearances on “Oprah” and other TV shows, has lost his front right leg to bone cancer.

Veterinarians found a tumor on his front paw several months ago, and diagnosed the condition as osteosarcoma, a form of malignant bone cancer that strikes dogs and cats in addition to humans.  Acting with extreme caution, the doctors removed his entire front right leg to prevent the possible spread of the cancer.

For the past weeks, Gibson has been recuperating at his home in Grass Valley, a Gold Rush-era town about 60 miles east of Sacramento in the Sierra foothills, nursed by his owner and human companion, Sandy Hall.  When the news broke, Hall says that well wishers from around the world have been calling and sending emails to see how he’s doing.  The answer to that question, as these first exclusive pictures show, is just fine.

“Gibson is getting back into life pretty well, actually,” Hall recently told About.com’s Buck Wolf.  “Dogs adapt quickly to challenges.  Much better than us two-legged humans!”

Gibson is a certified therapy dog and just this week resumed his work with cancer patients and others who need some cheering up from the friendly canine, making a return visit to the Brunswick Village assisted living community in Grass Valley.  “His ability to uphold his world title will continue to put smiles on people’s faces and uplift the spirit of those who are survivors of bone cancer,” Hall told a reporter.

Despite the loss of the leg, which hasn’t affected his height or his tallest dog title, Gibson has bounced back and has learned to walk, albeit with a bit of a limp, and even run short distances with Hall in toe.  It might be a few months before Hall lets him resume his famous stance, however.  “I don’t want him to stand up on my shoulders, which is the pose most people have come to expect from all our appearances and photo shoots,” Hall said.  “He might break his stitches if he did.”

Gibson just began the first in a round of chemotherapy treatments, which he is enduring well.  Getting him to eat is still a problem, however.  In these photos, Hall takes Gibson to visit one of his Vets, Melanie Curtis, D.V.M., at the Best Friends Animal Clinic in Grass Valley, for a check up.  Then the duo goes to a local pet food store to buy some special food to bulk the Great Dane up for his chemo treatments.  Along the way, fans stop to take pictures and pet the loveable Dane.

“He just puts a smile on people’s faces” Hall says.  “In one split second, people forget their cares and worries.  I just love him to death.  He’s such a great companion.”

Sandy and Gibson recently appeared on Animal Planet’s “Outrageous Animals, and despite the chemo, they’re celebrating the paperback release of their book “Gibson Speaks,” recounting his adventures with Oprah Winfrey, Jay Leno, Paris Hilton, and other alpha dogs, according to About.Com.

The medical expenses have been a real headache for Hall.  “All of our expenses have been exhausted,” she said.  “But we’re pushing on.”

For those who may wish to help, you can go to Gibson’s website:  www.gibsondog.com.