Evaluation of shark cartilage in patients with advanced cancer

A North Central Cancer Treatment Group trial


  • This study was conducted as a collaborative trial of the North Central Cancer Treatment Group and Mayo Clinic and was supported in part by Public Health Service grants CA-25224, CA-37404, CA-35113, CA-63849, CA-63848, CA-35195, CA-35272, CA-35269, CA-35103, CA-35101, CA-60276, CA-52352, CA-37417, CA-35448.

  • Additional participating institutions include: CentraCare Clinic, St. Cloud, MN 56301 (Harold E. Windschitl, M.D.); Siouxland Hematology-Oncology Associates, Sioux City, IA 51105 (Donald Wender, M.D.) Iowa Oncology Research Association CCOP, Des Moines, IA 50314 (Roscoe F. Morton, M.D.); Toledo Community Hospital Oncology Program (Paul L. Schaefer, M.D.); Medcenter One Health Systems, Bismarck, ND 58506 (Edward J. Wos, D.O.); Cedar Rapids Oncology Project CCOP, Cedar Rapids, IA 52403 (Martin Wiesenfeld, M.D.); Meritcare Hospital CCOP, Fargo, ND 58122 (Preston Steen, M.D.)



Shark cartilage has been a popular complementary or alternative medicine intervention. The basis for this popularity is the claim that sharks rarely get cancer because of the high proportion of cartilage in the shark's body. However, early studies were equivocal. Therefore, a clinical trial was conducted to look at the impact of shark cartilage in patients with advanced cancer. The primary goal of this trial was to determine whether a shark cartilage product improved overall survival for patients with advanced cancer who were getting standard care. Secondary research goals were to evaluate toxicities, tolerability, and quality of life associated with this shark cartilage product.


The study was a two-arm, randomized, placebo-controlled, double-blind, clinical trial. Patients with incurable breast or colorectal carcinoma had to have good performance status and organ function. Patients could be receiving chemotherapy. Patients were all to receive standard care and then to be randomly selected to receive either a shark cartilage product or an identical-appearing and smelling placebo 3 to 4 times each day.


Data on a total of 83 evaluable patients were analyzed. There was no difference in overall survival between patients receiving standard care plus a shark cartilage product versus standard care plus placebo. Likewise, there was no suggestion of improvement in quality of life for patients receiving the shark cartilage, compared with those receiving placebo.


This trial was unable to demonstrate any suggestion of efficacy for this shark cartilage product in patients with advanced cancer. Cancer 2005. © 2005 American Cancer Society.