"This is the best thing that's come along for colon cancer prevention in 20 years," he tells WebMD.
The combination treatment worked so well that the study was halted early.
"We're all pretty excited," says Roy Herbst, MD. "The data is pretty extraordinary."
The study was presented here at the annual meeting of the American Association for Cancer Research. Herbst, a cancer specialist at the University of Texas M.D. Anderson Cancer in Houston, moderated the session.
Colorectal cancer will strike about 150,000 Americans in 2008. It will kill about 50,000 men and women, according to the American Cancer Society.
Reduction in Risk of Multiple Colon Growths
Meyskens and colleagues studied 375 people who had at least three colorectal polyps, also known as adenomas, removed.
They were randomly assigned to treatment with either a combination of DFMO and sulindac, or placebo.
After three years, colonoscopy exams showed that 12.3% of patients given the drug combination had developed a new polyp, compared with 41.1% of patients given a placebo. This translates to a 70% reduction in risk.
"Even more remarkable was that there was a 92% reduction in the risk of advanced adenomas that are more likely to go on to cancer," Meyskens says. A total of 0.7% of patients in the treatment group had advanced adenomas -- such as those that are 1 centimeter in size or larger or have signs of abnormal cell growth under the microscope (dysplasia) -- vs. 8.5% in the placebo group.
"The real home run: A 95% reduction in multiple adenomas," Meyskens says. A total of 0.7% of patients in the treatment group developed more than one adenoma, versus 13.2% in the placebo group.
There was no significant difference in the rate of serious side effects, including heart attacks and strokes, between the two groups.