M. D. Anderson Participates in Largest Prostate Cancer Prevention Study Ever Conducted

The University of Texas M. D. Anderson Cancer Center is recruiting men for the largest prostate cancer prevention study ever conducted.

M. D. Anderson is among more than 400 sites across the United States, Canada and Puerto Rico participating in the Study of Selenium and Vitamin E Cancer Prevention Trial, known as SELECT. Coordinated by the Southwest Oncology Group and funded by the National Cancer Institute, the Phase III clinical trial plans to enroll 32,400 men. As one of the largest participating sites, M. D. Anderson intends to recruit 2,000 participants for the project.

Dr. Scott M. Lippman, professor and chairman of M. D. Anderson's Department of Clinical Cancer Prevention, serves as a national SELECT study coordinator.

"SELECT is a unique scientific and clinical opportunity to improve people's lives," says Dr. Lippman. "This historic trial is readily available to people of every social and ethnic background and includes clinical and laboratory - or translational - studies to advance our understanding of cancer prevention."

The study of selenium and vitamin E is based on secondary analysis of data from two previous cancer prevention trials. In a study of selenium versus placebo to prevent non-melanoma skin cancer, results showed that although the supplement did not reduce the risk of skin cancer, selenium did reduce prostate cancer incidence by two-thirds.

Similarly, in a lung cancer prevention study of Alpha-Tocopherol Beta-Carotene conducted in Finland, vitamin E did not prevent lung cancer. However, men receiving vitamin E showed a one-third reduction in prostate cancer incidence and a 40 percent reduction in prostate cancer mortality.

Despite progress in the early detection and treatment of the disease, prostate cancer continues to be a significant health risk for all men, with African-Americans at the highest risk of getting, and dying from, the disease. The American Cancer Society estimates that more than 198,000 new cases will be diagnosed this year and more than 31,500 men will die from prostate cancer. African-American men account for a 60 percent higher incidence of the disease and are twice as likely to die from prostate cancer than men of other ethnic backgrounds.

"Given these alarming statistics, SELECT will place a strong emphasis on recruiting African-Americans to participate, with a national recruitment goal of 6,500 black men," says Dr. Elise Cook, assistant professor of clinical cancer prevention, and SELECT's principal investigator at M. D. Anderson. "Locally, M. D. Anderson hopes to recruit 400 African-Americans into the trial."

Prospective SELECT participants must be healthy males at least 55 years old - 50 if African-American; never diagnosed with prostate cancer; cancer-free, with the exception of non-melanoma skin cancer, for the last five years; and must recently have completed a digital rectal exam, or DRE, and prostate specific antigen blood test, or PSA, both with normal results. Potential participants also will go through a process known as informed consent, during which they learn about the potential benefits and risks of selenium and vitamin E before deciding whether to participate in SELECT.

Once a man enrolls in the study, he must stop taking any vitamin supplements containing vitamin E and/or selenium and is assigned to one of four groups. He will receive SELECT study drugs consisting of either 200 micrograms of selenium and a placebo; 400 milligrams of vitamin E and a placebo; 200 micrograms of selenium and 400 milligrams of vitamin E; or two placebos - all for up to 12 years.

The study drugs and a supplementary multivitamin not containing vitamin E or selenium will be provided at no charge for all trial participants. The same multivitamin will be available for participants' significant others free of charge for the duration of the trial. Study volunteers will come to M. D. Anderson for follow-up examinations every six months and it will be recommended that they have annual DRE and PSA tests.

Selenium and vitamin E are associated with some side effects. Side effects of high-dose selenium include hair and nail changes, abdominal pain and taste bud modifications, Dr. Cook says. Because SELECT uses a lower selenium dose, Dr. Cook does not expect such reactions during the prostate cancer prevention trial.

A greater health risk, explains Dr. Cook, is associated with vitamin E. In the Finnish ATBC study, men with uncontrolled hypertension that took vitamin E had increased incidence of stroke. To diminish this risk, SELECT incorporates strict blood pressure guidelines for eligible men.

SELECT researchers hope to follow the success of the breast cancer prevention trial that found that the drug tamoxifen can prevent breast cancer in women at higher risk for developing the disease. M. D. Anderson recruited 300 women to the national study, more than any of the other 270 participating sites.

"What we have been able to achieve for women, we hope to duplicate for men with SELECT," says Dr. Cook. "Through the breast cancer prevention trial, tamoxifen has proven to reduce a woman's risk of getting breast cancer and is now an approved preventive agent for the disease. In the not-too-distant future, we hope to offer men everywhere a pill - such as selenium or vitamin E - that may be able to prevent prostate cancer."

Men interested in joining the study can call the "SELECT line" at M. D. Anderson at (713) 794-4400. For online information about SELECT, visit the M. D. Anderson Web site at http://www.mdanderson.org select. Additional information is available at the Southwest Oncology Group's Web site by accessing http://www.swog.org and choosing "SELECT," or at the National Cancer Institute's Web site, http://www.cancertrials.gov/select.

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©2006 Texas Medical Center

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