Prostate Cancer Prevention Trial Opens
32,000 Men Sought To Test Vitamin E And Selenium
Healthy men age 55 and older are needed for the largest- ever prostate cancer
prevention study, launched today by the National Cancer Institute (NCI) and a
network of researchers known as the Southwest Oncology Group (SWOG). The
Selenium and Vitamin E Cancer Prevention Trial, or SELECT, will determine if
these two dietary supplements can protect against prostate cancer, the most
common form of cancer, after skin cancer, in men. The study will include a total
of 32,400 men.
More than 400 sites in the United States, Puerto Rico, and Canada are recruiting
participants for SELECT, which will take up to 12 years to complete.
SELECT is the first study designed to look specifically at the effects of
vitamin E and selenium, both separately and together, in preventing prostate
cancer.
"We are looking for quite a few good men to join SELECT because it is an
incredibly important prostate cancer prevention study," said Charles A. Coltman,
Jr., M.D., chairman of SWOG and director of the San Antonio Cancer Institute in
Texas. "Previous research with vitamin E and selenium -- in studies focused on
other kinds of cancer -- suggested that these nutrients might prevent prostate
cancer. SELECT is focused on prostate cancer and, when the study is finished, we
will know for sure whether these supplements can prevent the disease."
During this year alone, prostate cancer will be diagnosed in about 198,100
Americans and more than 31,500 men are expected to die of the disease. Risk
factors for the disease include being over age 55, being black, or having a
father or brother with prostate cancer.
"It is crucial that men of all races and ethnic backgrounds participate in
SELECT," said Leslie Ford, M.D., associate director for clinical research in
NCI's Division of Cancer Prevention. "And since African-American men have the
highest incidence of prostate cancer in the world, we especially encourage them
to consider joining this trial." The disease also strikes black men at a younger
age, so they will be 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
SELECT.
"The men who join SELECT not only have a chance to prevent prostate cancer for
themselves, but they also may help their sons and grandsons live free from the
disease," said Ford.
Selenium and vitamin E, both naturally occurring nutrients, are antioxidants.
They are capable of neutralizing toxins known as "free radicals" that might
otherwise damage the genetic material of cells and possibly lead to cancer.
These nutrients were chosen for study because of the results of two other large
cancer prevention trials.
In a study of selenium to prevent nonmelanoma skin cancer in 1,000 men and
women, reported in 1996*, investigators found that while the supplement did not
reduce skin cancer, it did decrease the incidence of prostate cancer in men by
more than 60 percent.
Another trial, published in 1998**, in which beta carotene and vitamin E were
tested to prevent lung cancer in 29,000 Finnish men who smoked, those who took
vitamin E had 32 percent less prostate cancer. Neither beta carotene nor vitamin
E prevented lung cancer. In fact, the men who smoked and took beta carotene were
more apt to get lung cancer and die from it than men who didn't take this
supplement.
"SELECT is the critical next step for pursuing the promising leads we saw for
the prevention of prostate cancer," said Ford, who is responsible for all
aspects of NCI's involvement in SELECT. "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 investigators hope to recruit all
the study participants during the first five years of the trial, so that each
man can be followed for at least seven years.
Men in the study will visit their study site once every six months. Upon
enrollment, they will be assigned by chance to one of four groups. 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. A third group will take
both selenium and vitamin E. And a final group will be given two placebos.
Men who join SELECT will not need to change their diet in any way, but they must
stop taking any supplements they buy themselves that contain selenium or vitamin
E. If participants wish to take a multivitamin, SWOG will provide, without
charge, a specially formulated one that does not contain selenium or vitamin E.
Men may be able to participate in SELECT 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
nonmelanoma skin cancer, in the last five years
--are generally in good health
To read a Q&A about SELECT, go to:
http://newscenter.cancer.gov/pressreleases/SELECTQandA.html
For more information about SELECT and a list of participating centers:
--In the United States (including Puerto Rico), call the National Cancer
Institute's Cancer Information Service at 1-800-4-CANCER (1-800-422-6237) for
information in English or Spanish. The number for callers with TTY equipment is
1- 800-332-8615.
--In Canada, call the Canadian Cancer Society's Cancer Information Service at
1-888-939-3333 for information in English or French.
Visit NCI's Web site at http://cancer.gov/select
or visit SWOG's Web site at
http://swog.org and choose SELECT.
SELECT Audio-Visual Materials
To listen to a radio news story about SELECT, visit
http://www.radiospace.com/nihhome.htm.
Scroll down to CURRENT, RECENT AND UPCOMING REPORTS and click on 7/24/01 story
on SELECT.
To view an on-line copy of the Video News Release about SELECT, visit
http://www.streamonsite.com/hendrick/nci.ram
To view an image of the crystalline structure of Vitamin E, go to:
http://newscenter.cancer.gov/pressreleases/SELECTcrystal.gif
To view an image of the chemical structure of Vitamin E, go to:
http://newscenter.cancer.gov/pressreleases/SELECTchemistry.gif
To view an image of the prostate, go to:
http://newscenter.cancer.gov/pressreleases/SELECTprostate.gif
To view an image Vitamin E capsules, go to:
http://newscenter.cancer.gov/pressreleases/SELECTVitEpill.gif
To view an image selenium capsules, go to:
http://newscenter.cancer.gov/pressreleases/SELECTselenium.gif
To view an image selenium and Vitamin E capsules, go to:
http://newscenter.cancer.gov/pressreleases/SELECTbothpills.gif
Four pharmaceutical companies are providing selenium and vitamin E capsules and
multivitamins for the study: Roche Vitamins Inc., Parsipanny, N.J.; Sabinsa
Corporation, Piscataway, N.J.; Nutricia Manufacturing USA Inc., Greenville,
S.C.; and BioAdvantex Pharma Inc., Mississauga, Ontario, Canada.
*Clark L.C., Combs GF Jr, Turnbull B.W., et al. Effects of selenium
supplementation for cancer prevention in patients with carcinoma of the skin. A
randomized controlled trial. Nutritional Prevention of Cancer Study Group. "JAMA"
276:1957-1963, 1996.
**Heinonen OP, Albanes D, Huttunen JK, et al. Prostate cancer and
supplementation with alpha-tocopherol and beta- carotene: incidence and
mortality in a controlled trial. "J. Natl Cancer Inst" 90:440-6, 1998.