Selenium, a natural mineral found in multivitamins and in many foods such as grains, corn, fish and animal organ meats, was originally investigated as a potential method of preventing skin cancer. "Previous research with vitamin E and selenium, in studies focusing on other types of cancer, suggested that together these nutrients might also prevent prostate cancer," says S. Bruce Malkowicz, MD, associate professor of Urology and principal investigator of the study. "What makes this study so appealing is that taking vitamin E and selenium, a natural vitamin and mineral found in many common foods, is completely non-toxic when taken in regulated dosages."
Penn, the coordinating site for 15 other Pennsylvania locations, is one of more than 400 sites in the United States, Puerto Rico, and Canada recruiting participants for this trial which is the largest-ever for prostate cancer prevention. The Selenium and Vitamin E Cancer Prevention Trial, or SELECT, is sponsored by the National Cancer Institute and the Southwest Oncology Group. It will include a total of 32,400 men and may take up to 12 years to complete.
Men of all races and ethnic background are encouraged to participate in the trial. African-American men have the highest incidence of prostate cancer in the world and are especially encouraged to consider joining the trial. The disease also strikes black men at a younger age, so they are eligible to enroll in the study at age 50, vs. age 55 for other racial and ethnic groups. There is no upper age limit for participation in the trial.
Selenium and vitamin E are antioxidants, capable of neutralizing toxins known as "free radicals," that might otherwise damage the genetic material of cells and possibly lead to cancer. These two naturally occurring nutrients were chosen for study because of the inadvertent results of two other large cancer prevention trials, one for non-melanoma skin cancer and the other for lung, in which prostate cancer rates were significantly reduced.
"This trial is the critical next step for pursuing the promising leads we've seen for prostate cancer prevention," said Malkowicz. "The only way to determine the real value of these supplements for prostate cancer is to do a large clinical trial focused specifically on this disease."
Study participants will be followed for five years and only have to visit the study site once every six months. Men may be able to participate in the SELECT trial if they:
Are age 55 or older; age 50 or older for black men;
Have never had prostate cancer and have not had any other cancer, except non-melanoma skin cancer, in the last five years;
Are generally in good health.
For more information about the selenium and vitamin E prostate cancer prevention trial at the University of Pennsylvania Cancer Center, please call 1-800-789-PENN and ask for the SELECT study.