Updated 12 August 2020

It turns out dinosaurs got cancer too

Scientists have discovered that cancer has been around for millions of years.

  • Scientists discovered bone cancer in a horned dinosaur that lived 76 million years ago
  • Initially, the abnormality was thought to be a healing fracture
  • This discovery could help us better understand modern ailments

It turns out cancer has been around since even before humans walked the earth.

Scientists recently discovered that a dinosaur's malformed leg was afflicted with bone cancer – the first discovery of its kind.

30 years after misdiagnosis

According to the study, published The Lancet Oncology, the 76 million-year-old bone of a centrosaurus, which was originally found in the Dinosaur Provincial Park in Alberta, Canada, in 1989, was initially diagnosed as a healing fracture.

But more than 30 years later, dinosaur experts from the Royal Ontario Museum and McMaster University proved that it was, in fact, a case of osteosarcoma, the most common type of bone cancer that generally affects the knee in humans. 

READ | ‘I was diagnosed with stage 3 bone cancer – I thought my life was ending’ 

Help of modern technology

The multi-disciplinary group of scientists, while on a trip to the Royal Tyrrell Museum in 2017, decided to investigate the bone after noticing that it looked strange, according to

With the help of modern medical technology and experts in pathology, radiology, orthopaedic surgery, and palaeopathology, they used scans to look at the bone's cellular level, and came to the conclusion that what looked like a fracture was actually cancer – and reconstructed how the cancer would have progressed from its early stages.

They also compared the fossil to bones of other centrosauruses and observed significant differences.

Larger than an apple, the tumour was centred on the horned dinosaur's shin. 

READ MORE | How giant dinosaurs evolved to stay cool

First confirmation of dinosaur cancer

According to one of the authors of the study, David Evans, scientists have often theorised that dinosaurs may have had cancer, but this is the first time that there is actual confirmation of the hypothesis. 

"We are as confident in this being osteosarcoma as we would be in a human presenting w[ith the] same findings," wrote Evans on Twitter. 

Did the cancer kill it?

While the bone cancer was at an advanced stage, it wasn't what tolled the death knell for this dinosaur.

The bone was discovered in a mass grave of centrosaurus bones, indicating that it died with its herd during a flood. However, the cancer would have crippled it, making it an easy target for predators if it weren't protected by its herd.

This discovery creates a better framework for diagnosing diseases in extinct animals like dinosaurs, and provides insight into the evolution and pathology of ailments humans are facing in the modern world.

READ | Canine bone cancer vaccine hints at a human version

Image credit: Pixabay


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