Prostate Cancer Research is Adding Years to Men's Lives

Prostate cancer has been under the medical research spotlight in a big way for a little more than a decade, and the flurry of activity is starting to show good results through testing and diagnosis refinements and the development of effective new drugs.

The primary function of the prostate gland is to secrete the fluid that moves sperm forward during ejaculation. The prostate is highly prone to cancer, and the American Cancer Society estimates the number of deaths resulting from prostate cancer at 30,000 each year. But recent years have shown a dramatic drop in the number of men who present with the disease in its advanced stages.

"Prostate cancer is a disease that's very prevalent in American society," said William A. See, MD, Professor and Chair of the Medical College of Wisconsin Department of Urology. "It's estimated that one in six men will be affected by prostate cancer in their lifetimes, and that is at least twice as high as any of the other cancers one hears about as relates to men.

"Although it may start relatively early in a man's life, prostate cancer is one that is commonly detected as men age. Many of us engage in this model of delayed gratification, whereby we work hard when we're young with the anticipation that we're going to realize the golden years. Unfortunately, prostate cancer deprives many men of the full benefit of those golden years."

Dr. See noted that prostate cancer is the most commonly diagnosed cancer in men, the second leading cause of cancer-related deaths in men, and ranks eleventh in terms of life expectancy lost from any disease. "It deprives men of both quality and quantity of life," he said.

New Efforts Reveal Clues About Cause
"Like many cancers, prostate cancer represents deranged cell growth," said Dr. See. "The uncontrolled proliferation of prostate cancer cells culminates in spread throughout the body-an invader that's really 'the enemy within' that results in the patients demise."

Large-scale research is now revealing clues to the causes of prostate cancer, leading to better prevention and treatment. "I think that's one of the very exciting things that's happened over the past decade," said Dr. See. "Ten or fifteen years ago prostate cancer was sort of a closet disease. There were a lot of societal and cultural mores and misgivings about the disease and what it represented.

"A positive thing that's happened over the last decade is that, for lack of a better term, prostate cancer has come out of the closet. There has been heightened public awareness of the relevance of this disease, and commensurate with that heightened public awareness there has been increased federal research emphasis in this area in terms of dollars that have been poured into prostate cancer study."

That research emphasis has had a profound impact. "We've drawn a lot of very high quality researchers into the field of prostate cancer," said Dr. See. "As a consequence, we have made very significant progress into the understanding of how prostate cancer develops."

Dr. See described prostate cancer as "probably a combination of both nature and nurture. It's both who you are and where you've been," he said. "There is certainly a genetic predisposition to prostate cancer in some individuals. At the same time, in many individuals there are some acquired genetic defects that occur as a consequence of lifestyle, what you eat, where you go, which together factor into your risk of developing prostate cancer."

Finding Better Diagnostics and Drugs
Changes in the way prostate cancer is diagnosed are hot topics for study and discussion among health care practitioners. PSA (prostate specific antigen) blood testing is the front line screen for prostate cancer. As prostate cancer develops, a protein measured by the PSA test goes up. The optimal age to begin PSA testing, the frequency of testing, as well as the optimal value to detect cancer, remain under investigation. At present, it is recommended that men over 50 be checked annually.

"Historically, 50% of men with prostate cancer presented with disease that had already spread throughout the body," said Dr. See. "Today, fewer than 5% present with what we would term advanced disease. The reasons for that are twofold. One is the heightened public awareness. The second is the availability of the PSA blood test. Widespread use of PSA screening has really shifted the stage of disease at which men present."

Clinical trials of drugs and element-vitamin combinations are offering promise in limiting prostate cancer recurrence and in preventing it in the first place. One large-scale national trial, which is being led by Dr. See, has shown to date that the hormonal treatment bicalutamide (sold as Casodex) cuts the risk of recurrence by more than 40%.

Another trial indicates that finasteride (sold as Proscar) may reduce the risk of developing prostate cancer. Other studies using dustasteride (sold as Avodart) and selenium-Vitamin E (known as the SELECT trial) are in progress to evaluate possible prevention benefits. Froedtert & Medical College participate in the Casodex, Avodart and SELECT trials. Dr. See stressed that several more years of trial will be needed to fully determine the benefits of these and other drug treatments.

"For the first time in recorded history, we are now seeing a decline in prostate cancer mortality," said Dr. See. "There are lots of potential reasons for that, but I've got to believe that one of the reasons is early detection. And, one of the very important studies in this past year looked to see whether doing nothing in a group of middle-aged men with not terribly aggressive looking prostate cancer was equivalent or better than removing the prostate. This trial was published in the New England Journal of Medicine and came out of Scandinavia, and for the first time demonstrated that active treatment improved what we call disease-specific survival."

"You need to be careful, as you look at that data, not to jump to the conclusion that every man with a diagnosis of prostate cancer needs treatment. That's absolutely not true. But it does tell us that there is benefit to therapy for men with a survival that we would anticipate to be in excess of ten years."

Dan Ullrich
HealthLink Contributing Writer

For more information on this topic, see the HealthLink article Prostate Cancer PSA Testing Faster, More Specific.

MCW Health News presents up-to-date information on patient care and medical research by the physicians of the Medical College of Wisconsin.