Sharks Get Cancer Too

FDA Consumer, July, 2000

Cancer found in sharks casts doubt on the usefulness of shark cartilage pills to cure or prevent cancer, scientists from Johns Hopkins University and George Washington University reported April 5 at the annual meeting of the American Association for Cancer Research. Proponents of shark cartilage supplements have believed that since sharks did not appear to get cancer, their cartilage may block the growth of new blood vessels that supply nutrients to a tumor and cause it to spread.

The new data challenge that belief. The researchers examined data in the National Cancer Institute's Registry of Tumors in Lower Animals and found 40 cases of tumors in sharks and related fishes. Researchers noted that their study can't rule out the possibility that scientists may one day find a useful cancer treatment in cartilage from sharks or other animals.