SELECT Study

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Bob Rozman knows firsthand about the reality of prostate cancer. “When I turned 50 years old, my wife Kathy insisted I start to go to the doctor regularly and get every test in the book for prostate cancer.” The London, Ontario, resident is now glad he listened because several years ago, Bob received the news. “You don’t remember a word for the next two hours,” says Rozman, as he recalls the day he was diagnosed with prostate cancer – the most common type of cancer, after skin cancer, affecting men.

Although very little is known about the disease, and it is not yet clear why prostate cancer develops, numerous research studies have provided insight into several factors that may play a role. There is a definite link to age: the disease tends to affect men over age 50, with 80 per cent of prostate cancers diagnosed in men over age 65. Strong risk factors also include a family history of prostate cancer, high levels of testosterone and a high-fat, low-fibre diet. Men of African descent are also at an increased risk due to genetics.

According to the Prostate Cancer Research Foundation of Canada, one in every eight Canadian men will develop prostate cancer in his lifetime, and one in four of those men will die from the disease. In Ontario alone, approximately 6,400 men will be diagnosed with prostate cancer this year and 1,600 will die of it.

Considering that approximately five million Canadian men are now in their prostate cancer prone years, this makes prostate cancer a leading threat to the health and lives of men. Numbers are expected to rise significantly as aging baby boomers enter the years where they will be at risk for prostate cancer.

In response to these startling numbers, Canada is making a significant contribution to the largest ever prostate cancer prevention study. London Health Sciences Centre and London Regional Cancer Centre, in association with the Lawson Health Research Institute in London, Ontario, are involved in the North American SELECT study on prostate cancer.

The SELECT study (Selenium and Vitamin E Cancer Prevention Trial) is a 12-year investigation taking place in over 400 sites across Canada, the United States and Puerto Rico. Its purpose is to determine whether taking two dietary supplements, selenium and vitamin E, either separately or together, can prevent the occurrence of prostate cancer in men. Previous studies in the US and Finland have indicated that these two supplements may decrease the incidence of prostate cancer, but those studies were not exclusive in their investigation of prostate cancer. The SELECT study is the next step in research to determine if the supplements can prevent this disease.

The SELECT study is sponsored by the U.S. National Cancer Institute and coordinated by an international network of researchers known as the Southwest Oncology Group. The study will involve more than 32,000 healthy men age 55 and older (50 or older for black men), with no prior history of prostate cancer, whose physical progress and well being will be monitored for 7 to 12 years.

“This is a long-term study in which the participants have regular contact with the study site every six months. An annual PSA (prostate specific antigen) and DRE (digital rectal exam) will be included as part of the study protocol. If there is a change in prostate health, these men may benefit from early detection,” says Lawson Health Research Institute and London Health Sciences Centre, Research Co-ordinator Ann-Marie Waschenko.

Men who participate in this study will be randomly assigned to one of four treatment groups receiving two capsules a day. One group will take 200 micrograms of selenium daily plus an inactive capsule, or placebo, that looks like vitamin E. Another group will take 400 milligrams of vitamin E daily along with a placebo that looks like selenium. Another group will take both selenium and vitamin E. A final group will be given two placebos. Neither the participants, nor the researchers, will know who is receiving the selenium and vitamin E, or the placebos.

Previous studies have shown that these amounts of selenium and vitamin E are safe in healthy men. In fact, the supplements are both naturally occurring nutrients required for normal human health. Selenium is a trace element that is necessary for the normal functioning of the immune system and the thyroid gland. Natural sources of selenium include brewer’s yeast, meats, egg yolks, dairy products, seafood, whole grains and Brazil nuts. Vitamin E is a fat-soluble vitamin that exists in a variety of forms in many foods, including vegetable oils, nuts, wheat germ, margarine, whole grains, liver, and sunflower seeds.

Selenium and vitamin E are also both powerful antioxidants that protect human cells against the toxic effects of free radicals. Free radicals are the products of normal oxygen metabolism. They can damage cells and may contribute to the development of some chronic diseases, including cancer.

“Previous research involving vitamin E and selenium suggested that these nutrients might prevent prostate cancer, but we don’t know for sure. SELECT will determine whether these supplements can prevent prostate cancer,” says Dr. Joseph Chin, Chair, Division of Urology at London Health Sciences Centre.

London, Ontario is one of 12 Canadian SELECT study sites, and one of the seven sites in Ontario. This site is currently the number one centre for recruitment in North America for the SELECT study, making London the leading site in Canada, with a recruitment total of over 500 men, just ahead of Vancouver. “Canadian men have shown a strong interest in the program as indicated by London and Vancouver being top recruiters. Men in Southwestern Ontario have made London the number one recruiting site in North America, proving that they are interested in this very worthwhile and timely project,” says Nancy Pus, Urology Researcher at Lawson Health Research Institute at London Health Sciences Centre.

Over the past decade, the incidence of prostate cancer has increased dramatically. This can be attributed to the fact that men are now living longer, consequently increasing their chance of developing the disease over a longer period of time. Because there is a greater awareness of the disease, prostate cancer is also being diagnosed more often, rather than progressing undetected.

If prostate cancer is detected early and treated, men have an excellent chance of recovery. Since often there are no symptoms of prostate cancer during very early stages of the disease, it is recommended that every male over age 40 have regular exams by a physician.

“I encourage all my friends and everyone I know to go to their doctor about this,” says Bob Rozman. He insists that early detection saved his life. While many men put off the annual exam for prostate cancer, often wary of the discomfort of the procedure, Rozman says he didn’t find the DRE (Digital Rectal Exam) to be painful, “Zero pain: absolutely none.” His course of treatment for the cancer included surgery to remove the prostate. “Because I was younger, we decided that would be the best thing.”

As a prostate cancer survivor, Bob Rozman knows the importance of raising the profile of the disease and encouraging early detection. However, continued research is the best possible hope for a future cure of this growing disease. Researchers are hopeful that information learned from the SELECT study will help future generations of men avoid prostate cancer.

For information about participating in the SELECT Study, or to find out more about the study, call the Canadian Cancer Society’s Cancer Information Service at 1-888-939-3333. Information is also available at the National Cancer Institute’s Web site at http://cancer.gov/select; or visit the Southwestern Oncology Group’s Web site at http://swog.org and choose the “SELECT” option. You can also call your local SELECT Study Site for information about how to join. Men interested in joining the London site study can contact London Health Sciences Centre, Research Co-ordinator Ann-Marie Waschenko at (519) 685-8261.