In the latest research into the benefits of alternative therapies for cancer, shark cartilage did not help patients with lung cancer live longer but ginseng and flaxseed appeared to offer some benefit to cancer patients.
Shark cartilage products have been marketed for years as "alternative" products for treating disease by several firms.
A Canadian company, Aeterna Zentaris has been developing one such product Neovastat as a licensed pharmaceutical but in March the company stopped development of Neovastat following a clinical trial.
The availability and common use of alternative products and supplements, along with queries from cancer patients, prompted the clinical trials in order to determine whether these products were helpful.
In the shark-cartilage clinical trial which was led by Dr. Charles Lu of M. D. Anderson Cancer Centre in Houston and sponsored by the National Cancer Institute, the researchers had reason to believe the cartilage might work as it has been found to contain factors that can impede blood-vessel formation, and cutting off blood to tumours has been proven effective with other drugs.
The study tested 379 lung cancer patients who either drank Neovastat or a product that tasted just like it.
But the large study shows quite definitively that the product did not work say experts.
Dr. Lu says the patients had stage 3 lung cancer, which had spread extensively inside the lungs and which usually cannot be treated with surgery.
Everyone also received the standard lung cancer chemotherapy and radiation and it was found that the group that had the shark cartilage did not live any longer than the patients given placebo drinks.
Last year alone lung cancer was diagnosed in more than 174,000 Americans and killed more than 160,000.
Lung cancer kills 1.3 million people globally every year.
However in a study involving 161 men with prostate cancer, the results were more encouraging for flaxseed, though far less definitive.
After the prostates were removed, it was found the tumours of the men who had taken flaxseed had been growing about 30 to 40 per cent more slowly than for those who did not.
A study examining ginseng was also promising as it suggests ginseng it might help fight the fatigue which is common with cancer.
The studies were presented at the annual meeting of the American Society for Clinical Oncology.