Gibson, the California dog dubbed the tallest in the world by the Guinness Book of World Records died after a battle with bone cancer.
Standing at 42.6 inches tall from paw to shoulder, Gibson, the giant Harlequin Great Dane passed away last Friday near Sacramento, Los Angeles.
Born in 2002, Gibson took the title of the world's tallest dog from 'Harvey', who measured 41 inches, in 2004.
Weighing 180 pounds and measuring 7 feet 1 inch standing on his hind legs, Gibson worked as a therapy and special needs training dog, visiting care centres and schools throughout the California area.
Gaining world wide attention due to his huge frame he was diagnosed with bone cancer in his right front paw in April of this year.
Within ten days of his diagnosis, Gibson underwent a seven hour operation to remove the leg in a bid to prevent the cancer from spreading further.
The surgery was performed to prevent the cancer from spreading, and early tests showed positive results.
After the surgery, the harlequin Great Dane received follow up chemotherapy treatments as a precaution.
Last week, Sandy Hall, Gibson's owner, learned that the cancer had spread to Gibson's lungs and spine, at which point Gibson's doctor stated that there was no other medical treatment that would save Gibson.
"Last week Gibson began having trouble using his back legs," said Dr. Peter Walsh, Gibson's veterinarian, in a prepared statement.
"X-rays showed that the cancer had spread to his spine and his lungs. Ms. Hall made the very difficult decision based on her concern and love for Gibson to have him humanely euthanised.
"Gibson died peacefully in the loving arms of Ms. Hall."
