As pathologists examine sections of a patient's bone, the investigation looks grim. A cauliflower-like growth in the bone reveals chondrosarcoma, a cancerous bone disease.

The patient, however, is not around to hear the diagnosis, because it died during the Jurassic era, or about 135 million to 140 million years ago when dinosaurs dominated the earth. It was an Allosaurus.Its fossil remains, analyzed at Brigham Young University and at the Naval Hospital in San Diego, Calif., show that some dinosaurs had cancer.

BYU paleontologist Ken Stadtman discovered the Allosaurus humerus (arm) bone at the Dry Mesa quarry in western Colorado. From irregular cell structure and growths on the bone, Stadtman said he could detect the bone had been diseased.

"We knew the bone had pathology on it, but little beyond that," says Wade Miller, BYU paleontology professor and director of the university's Earth Science Museum. "We have just received news, however, that pathologists in San Diego confirm the disease as cancer."

To get the information, BYU worked through Leon Goldman, M.D., a professor emeritus from the Dermatology College of Medicine at the University of Cincinnati and a laser consultant at the San Diego Naval Hospital.

The discovery prompted Goldman to praise the BYU dinosaur find in a letter to Miller.

Miller also sees value in fossil research.

"By studying fossils, we may learn more of the history of some diseases," says Miller. "Discoveries such as carcinogenic material in dinosaurs should shed more light today on our understanding of cancer."

The Allosaurus "different lizard" was a large meat-eater that walked on its hind legs, measured more than 32 feet long and 13 feet tall and weighed more than two tons. It was a hunter that preyed on such gigantic sauropods as Apatosaurus and Diplodocus.