A group of Canadian researchers say they have discovered the first confirmed case of a dinosaur with malignant cancer, combining the skills used to analyze prehistoric fossils with modern methods used to diagnose humans.
In a study published Monday in the medical journal The Lancet Oncology, researchers led by the Royal Ontario Museum (ROM) in Toronto and McMaster University in Hamilton, Ontario, said the case suggested that malignant tumors, including cancers of the bones, “are deeply rooted in the evolutionary history of organisms.”
The researchers examined a bone from the lower leg of the centrosaurus apertus, a horned dinosaur that lived 76 to 77 million years ago. The bone itself was originally discovered in 1989 in the badlands of Dinosaur Provincial Park in southern Alberta, Canada, a UNESCO world heritage site and one of the richest regions for dinosaur fossils in the world.
The bone, which was visibly malformed, caught the attention of researchers on a trip to the Royal Tyrrell Museum in Alberta in 2017. A team of experts in human and dinosaur pathology gathered, including orthopedic surgeons.
The researchers examined and molded the bone, performed high-resolution CT scans, and cut the bone into extremely thin sections, examining it at the cellular level to track the progression of cancer in the bone, before diagnosing the dinosaur with osteosarcoma. The bone was then compared to a normal fibula bone from the same dinosaur species and to a human bone with a confirmed case of the same cancer.
Diagnosing aggressive cancer like this in dinosaurs has been elusive and requires medical expertise and multiple levels of analysis to correctly identify it, “said Dr. Mark Crowther, professor of molecular medicine and pathology at McMaster University, who also is a declared fan of dinosaurs and a volunteer at ROM.
Here, we show the unmistakable signature of advanced bone cancer in a 76-million-year-old horned dinosaur, It’s very exciting.
Dinosaur cancer was aggressive and advanced, said Dr. David Evans, a ROM paleontologist, and “would have had paralyzing effects on the individual and would have made him very vulnerable to the formidable tyrannosaurus predators of the time.”
He speculated that the large, herbivorous Centrosaurus apertus may have been protected by its place in a large protective herd, allowing it to survive much longer than it normally would with such a disease. Instead, its discovery in a huge bed of bones along with other fossils suggested that the dinosaur was killed along with a large herd by another lingering danger: a flood.
