Shark Cartilage May Not Prevent Cancer

SAN FRANCISCO--The American Association of Cancer Research conference met here and presented research that suggests sharks do get cancer, and shark cartilage should not be recommended as a dietary supplement for cancer prevention. Shark cartilage supplements were first recommended by I. William Lane, the biochemist who wrote the popular 1993 book Sharks Don't Get Cancer. He had found that out of 7,500 shark records catalogued by the Smithsonian, only 30 sharks had had tumors."That's a very low rate of cancer compared to other fish and humans," Lane said.

Co-presenters Gary Ostrander of Johns Hopkins University and John Harshbarger of Washington University School of Medicine reported they found 40 cases of cancer in sharks. They also cited research from the Nov. 1998 issue of The Journal of Clinical Oncology suggesting that shark cartilage extracts were ineffective as cancer therapies in humans. "There may someday be evidence that substances from shark cartilage have benefits in preventing or treating cancer," Ostrander said, "but now ingesting powders of the stuff to date has not been shown to have any benefit."

Additionally, the federal government is planning two major trials in human subjects with shark cartilage-based products. The National Cancer Institute (NCI) and the Center of Complementary and Alternative Medicine (NCCAM) are planning to test the drug in May with 750 lung cancer patients at the MD Anderson Cancer Center. The study will consist of two groups using chemotherapy and radiation but with one group given a shark cartilage drug and the other given a placebo.

The second trial, scheduled to begin later this year, will be sponsored by the National Institutes of Health (NIH) and Lane Labs, a company founded by Lane's son. BeneFin, a shark cartilage extract, will be tested on 600 terminally ill breast and colon cancer patients at the Mayo Clinic. For additional information about these studies, visit www.jco.org and nccam.nih.gov/nccam/fi/concepts/ce/shark.html.