Businesses that sell shark cartilage as a cancer cure or preventative have claimed for years that sharks never get cancer, but this week scientists from The Johns Hopkins University and George Washington University presented a detailed history of benign and malignant tumors found in sharks and related fishes.
At a news conference at the annual meeting of the American Association for Cancer Research, scientists noted that sharks can even get chondromascancers of the cartilage now being sold as a cancer cure. Their results come from a survey of data in the National Cancer Institute's Registry of Tumors in Lower Animals at George Washington University. Using very strict diagnostic criteria, scientists were able to find 40 cases of tumors in sharks and related fishes like skates and rays.
"People are out there slaughtering sharks and taking shark cartilage pills based on very faulty data and no preventative studies to show that it works," Gary Ostrander, Hopkins professor of biology and comparative medicine, says. "That's not only giving desperate patients false hope based on misinterpreted data, it's also taking a top-level predator out of an ecosystem, which could cause major disruptions in the ecosystem."
Ostrander and lead author John Harshberger, a professor at George Washington University who directs the Registry of Tumors in Lower Animals, note that the new study can't rule out the possibility that scientists may one day find a useful cancer treatment in cartilage from sharks or other animals. They also acknowledge that folk and alternative medicine can sometimes offer legitimate insights to the biomedical sciences.
For now, though, no proof exists that shark cartilage can have positive effects on cancer, and the pills' cost to patients, potential for interference with proven cancer treatments, and the potentially devastating impa
Contact: Michael Purdy
Johns Hopkins University