Canadian researchers say they have discovered the first known case of a dinosaur suffering from a deadly cancer. The evidence came from a fossil leg bone discovered in Alberta, Canada in 1989. The fossil was from a dinosaur called Centrosaurus. It was a four-legged plant eating animal about 6 meters long that lived between 76 and 77 million years ago. Examinations of the fossil showed the lower leg bone, called the fibula, was badly malformed. The scientists thought this was likely caused during the healing process of a broken leg. But new studies of the fossil led researchers to believe the malformation was probably caused by an aggressive bone cancer called osteosarcoma. The research team included medical professionals who study and diagnose cancers in humans.