A rare, ancient case of bone cancer has been found in a turtle ancestor

A 240-million-year-old fossil is the oldest known example of this disease in amniotes

Pappochelys rosinae

TRIASSIC TURTLE  An extinct ancestor of modern turtles called Pappochelys rosinae (illustrated) had bone cancer, the oldest known case in an amniote, a group that includes mammals, birds and reptiles.

Brian Engh/dontmesswithdinosaurs.com

A 240-million-year-old case of bone cancer has turned up in a fossil of an extinct ancestor of turtles. Dating to the Triassic Period, the fossil is the oldest known example of this cancer in an amniote, a group that includes mammals, birds and reptiles, researchers report online February 7 in JAMA Oncology

The fossilized left femur from the shell-less stem-turtle Pappochelys rosinae was recovered in southwestern Germany in 2013. A growth on the leg bone prompted a team of paleontologists and physicians to analyze the fossil with a micro CT scan, an imaging technique that provides a detailed, three-dimensional view inside an object.

“When we saw that this was not a break or an infection, we started looking at other growth-causing diseases,” says Yara Haridy, a paleontologist at the Museum für Naturkunde in Berlin. The verdict? Periosteal osteosarcoma, a malignant bone tumor. “It looks almost exactly like human periosteal osteosarcoma,” Haridy says.

“It is almost obvious that ancient animals would have cancer, but it is so very rare that we find evidence of it,” she says. The discovery of this tumor from the Triassic offers evidence that cancer is “a vulnerability to mutation deeply rooted in our DNA.”

tumor
BONE CANCER A team of paleontologists and physicians discovered that a fossilized femur of Pappochelys rosinae (front view shown with a micro CT scan image of the tumor) had periosteal osteosarcoma, a malignant bone cancer. Y. Haridy et al/JAMA Oncology 2019

Aimee Cunningham is the biomedical writer. She has a master’s degree in science journalism from New York University.