Several Types of Cancer are Considered Silent Killers When is silence not golden? When it's a killer. Several types of cancer are considered "silent killers." Colon, bowel, lung, stomach, rectal, liver and pancreatic cancers are often in advanced stages by the time their symptoms finally develop into red flags. In the group of silent killers, ovarian cancer is one of the quietest and most insidious. The American Cancer Society predicts that this disease will claim more than 16,000 deaths this year, while well over 22,000 new cases will be diagnosed. This mortality rate has remained fairly consistent for the past half century. Needless to say, the need for preventive measures against ovarian cancer can't be overestimated. Most studies conclude with a notation that further research is needed to confirm the findings. So it was refreshing to come across a new epidemiological study (one that examines health events among a population) immediately followed up with a laboratory study. Further research is still needed, but the first two steps have already been taken. Researchers at Harvard Medical School's Brigham and Women's Hospital (BWH) started out by questioning more than 1,200 subjects about their intake of herbal supplements. The cohort of subjects was evenly divided between women with ovarian cancer, and women without the disease. The data showed that the herbals these women used most often were ginkgo biloba, ginseng, echinacea, St. John's Wort, and chondroitin. When researchers compared the use of each supplement individually against cases of ovarian cancer, an interesting pattern emerged: Women who used ginkgo were much more likely to be in the healthy group. In fact, it appeared that when ginkgo was used for six months or longer, ovarian cancer risk dropped by as much as 60 percent. Research results like this are promising, but a single study might only reveal a coincidence. So the BWH team went to the lab to test their results. In a presentation for the American Association for Cancer Research's 4th annual Frontiers in Cancer Prevention Research last month, Bin Ye, M.D., and Daniel Cramer, M.D., of BWH showed that a small amount of ginkgolide (the biologically active component of ginkgo biloba) stopped the growth of ovarian cancer cells. In an American Association for Cancer Research news release, Dr. Ye said that it was "most likely" that ginkgolides have anti-inflammation and anti-angiogenesis properties that are effective against this cancer. (Angiogenesis is the development of new blood vessels, which help cancer tumors thrive.) Ginkgo biloba has is well known as a potential memory enhancer and an aid for cognitive function that might even be effective in treating the early symptoms of Alzheimer's disease. If you're thinking of supplementing with ginkgo, keep in mind that many herbalists and medical professionals who use alternative treatments believe the recommended daily dosage of 120 mg of ginkgo biloba is too low, and that the dosage should be 240 mg or more per day. The optimal dosage for any individual should be determined by weighing other health factors, other supplements or drugs being used, and only after consulting a doctor or medical professional. Also note that ginkgo may prompt gastrointestinal bleeding. Apparently this bleeding is slight, and usually happens when ginkgo is taken with other agents that are also known to prompt such bleeding, like aspirin or the anticoagulant drug warfarin. So for most people, bleeding shouldn't be a problem. However, there are other ginkgo side effects, including headaches and skin irritations. The culprit in these cases is ginkgolic acid, a toxic compound. It's generally accepted that five ppm (parts per million) is a safe maximum level for this acid. But some supplement manufacturers don't list ginkgolic acid on their labels, so be sure to read content labels carefully. For more information about ovarian cancer, you can check these e-Alerts: - "Phyto to the Rescue" (9/15/03) - How diet affects ovarian cancer risk
- "Rocket Food" (12/14/04) - How a common nutrient may lower ovarian cancer risk, while a component of milk products may increase risk
- "Reading the Code" (5/13/04) - How genetic factors may increase ovarian cancer risk
You can find these and other e-Alerts in the e-Alert archives at hsibaltimore.com. Sources:
"Ginkgo Biloba and Ginkgolides as Potential Agents for Ovarian Cancer Prevention" Abstract #3654, Presented 10/31/05, American Association for Cancer Research's 4th annual Frontiers in Cancer Prevention Research, aacr.org
"Ginkgo Biloba, Ginkgolides May Help Prevent Ovarian Cancer" News Release from the American Association for Cancer Research, 11/1/05, foodconsumer.org | 
