Scientists say they have, for the first time, found that dinosaurs suffered from osteosarcoma — an aggressive malignant cancer that afflicts humans today.
When a lower leg bone or fibula from a horned dinosaur called Centrosaurus apertus that lived 76 to 77 million years ago was unearthed in Dinosaur Provincial Park in Alberta, Canada, in 1989, the malformed end of the fossilized bone was originally thought to be a healing fracture.
But a more detailed analysis, using modern medical techniques that approached the fossil in the same way as a diagnosis in a human patient, revealed that it was osteosarcoma, a bone cancer that in humans today usually occurs in the second or third decade of life.
It’s an overgrowth of disorganized bone that spreads rapidly both through the bone and to other organs, including most commonly, the lung.
“Diagnosis of aggressive cancer like this in dinosaurs has been elusive and requires medical expertise and multiple levels of analysis to properly identify,” said Dr. Mark Crowther, a professor of pathology and molecular medicine at McMaster University in a press statement. “Here, we show the unmistakable signature of advanced bone cancer in (a) 76-million-year-old horned dinosaur — the first of its kind. It’s very exciting,” said Crowther, author of the paper, which was published in the journal Lancet Oncology recently.
The team analyzing the fossilized bone included professionals from diverse fields including pathology, radiology, orthopedic surgery, and paleopathology — the study of disease and infection in the fossil record.
The bone was examined, cast and CT scanned before a thin slice of the bone was studied under the microscope. Then, powerful three-dimensional reconstruction tools were used to visualize the progression of cancer through the bone. The investigators ultimately reached a diagnosis of osteosarcoma.
To confirm their diagnosis, the team compared the fossil to a normal fibula from a dinosaur of the same species, as well as to a fibula belonging to a 19-year-old man with a confirmed case of osteosarcoma.
The fossil specimen is from an adult dinosaur with an advanced stage of cancer that may have invaded other body systems; however, it’s not clear if the dinosaur was killed by cancer. It was found in a massive bone bed, suggesting it died as part of a large herd of Centrosaurus that was struck down by a flood.
(Article originally appeared on CNN Science)