The health of a very small gland has received a very large amount of attention in recent years. The battles of celebrities such as Louis Gosset Jr., Dennis Hopper, and Don Imus with prostate cancer have been well-publicized. Prostate health has been a featured topic on shows such as Anderson Cooper 390o and The Dr. Oz Show and in cover stories in magazines such as Newsweek, Men’s Health, and Consumer Reports on Health. By any measure, that’s a lot of attention paid to a gland that’s commonly described as being about the size of a walnut.
The greatest cause of concern with the prostate is prostate cancer. While cancer is generally the disease most feared by Americans, prostate cancer is the most feared cancer that affects men. Men (and the women who love them) have reason to be concerned. After skin cancers, prostate cancer is the most common cancer in men. Over 200,000 men are diagnosed with prostate cancer every year and more than 32,000 men die from prostate cancer each year in America. Despite these sobering statistics, there has been a slow but steady decline in prostate cancer deaths by about 30% since 1975.
Some doctors attribute this decline to early detection of prostate cancer. Like many other cancers, early detection and treatment can greatly increase survival chances. The introduction of the Prostate-Specific Antigen (PSA) test in the 1980s was supposed to revolutionize early detection for prostate cancer. Recent changes in the recommendations and conflicts between various health authorities, however, have made it difficult for the average man to know if this test is something they need or when they need it. This article will cut through some of this confusion.
The first question to answer is: What is the prostate gland and what does it do? The prostate is a donut-shaped gland that sits just below the urinary bladder and completely surrounds the urethra. It contains sections of glandular cells that excrete fluids into a number of ducts that lead into the urethra. The fluids these cells secrete form about 25% of the seminal fluid, including several substances that contribute to the survival of sperm and help the sperm reach the egg. The prostate is therefore very important in promoting reproductive success.
In most adult men, the prostate is actually closer in size to a golf ball than a walnut. It starts off as a very small organ, then grows greatly during puberty. Some men experience further growth of the prostate later in life. This can be either as a result of a tumor growing in the prostate or a condition known as Benign Prostatic Hyperplasia (BPH). BPH is not a form of cancer, but instead is an overgrowth of the glandular cells. Because the symptoms of prostate cancer and BPH are very similar, doctors will need to determine which condition a patient has.
In both diseases, this increase in size is generally unnoticed until the prostate becomes large enough to squeeze the urethra. The urethra passes directly through the center of the prostate on its way from the urinary bladder to the outside of the body, so when it gets to be too large, a man will experience difficulty starting or stopping urinating. This includes symptoms such as straining to urinate, a weak or intermittent urine stream, drizzling, or feeling a sense of incomplete emptying of the bladder. If the symptoms are due to prostate cancer and the cancer has spread to the bones, then it may also cause pain in the pelvis, ribs, or backbone.
Like BPH, prostate cancer involves an overgrowth of prostate tissue. The difference is that in prostate cancer the cells divide and grow out of control and can break away from the original tumor to travel to, and start new tumors in, other parts of the body. The typical prostate tumor originates from the glandular cells. The incidence of prostate cancer increases with each decade of life. The average age at first diagnosis is 72, and more than 75% of prostate cancer cases are found in men over 65.
American men have about a 1 in 6 chance of developing prostate cancer at some time in their life but only a 1 in 36 chance of dying from the disease. In fact, many men diagnosed with prostate cancer never receive treatment because of the slow growth and low risk of death from many tumors.
While generally these tumors grow slowly, some men have very aggressive tumors. This risk varies by race and age at first diagnosis. Prostate cancer that develops in a 40-year- old will tend to be more aggressive, grow faster, and have a greater risk of metastases than a prostate cancer that develops at age 80. African American men have the highest risk of developing prostate cancer, which also tends to develop earlier and more aggressively than in other demographic groups. The genes that regulate the growth, programmed cell death, and metastatic properties of prostate glandular cells are expressed differently in African American than in Caucasian men.
The two most common ways of detecting possible prostate disease are a digital rectal exam and the PSA test. The rectal exam is exactly what it sounds like – the doctor gently inserts a gloved finger into the rectum so they can feel the size and shape of the gland. Hard, lumpy, or otherwise abnormal areas will be cause for concern. The good news is that the examination is very brief.
The PSA test is a blood test that detects a protein produced by cells that line the ducts of the prostate gland. Normally, very small amounts of this protein are found in the bloodstream. When the prostate suffers injury or disease, however, the amount of PSA in the blood rises. In the late 1970s and early 1980s, scientists started identifying this protein and linking it to BPH and prostate cancer. In 1986 the first blood test for PSA was approved for use by the FDA. Because the prostate cells are the only cells in the body that produce PSA, it was considered a breakthrough in diagnostic tools.
Soon after the approval of this test, it became a standard tool to screen men for prostate cancer. By screening large numbers of men in early middle age, it was felt that prostate cancer would be caught before it advanced and hence cancer survival rates would rise. Indeed, the Roswell Park Cancer Institute where the PSA test was first developed calls it, “the centerpiece in the early warning system for prostate cancer,” and credits the test with saving the lives of more than 2 million prostate cancer survivors.
The last ten years have seen more research released about the relative risks and benefits of routine PSA screening. If a screen is supposed to catch the “big stuff” (that is, disease) and let the “little stuff” (that is, healthy men) through, this research is showing PSA is a less effective screen than had been believed. For example, one study found that 15% of the men with a “normal” PSA level actually had prostate cancer. The introduction of widespread PSA testing has dropped the rate of “latent” prostate tumors discovered at one institution from 4.8% to 1.2%. Latent tumors are prostate cancers that existed during life but which evaded detection and were only discovered on autopsy after death. Routine screening is therefore not finding as many prostate tumors as had been hoped.
On the other side of the coin, even if the PSA level is high the benefit of PSA screening has been called into question. A European study demonstrated only a 20% relative reduction in the risk of death from prostate cancer in men that are screened. They estimated that 1,410 men would need to be screened and 48 men treated in order to prevent 1 cancer death. A very broad study sponsored by the National Cancer Institute also found little impact of regular routine PSA screening on the chances for death from prostate cancer.
This newer information has changed the way doctors view PSA screening. The guidelines used to be simple but simple isn’t always correct. This is especially true when dealing with the complex environmental and genetic factors that lead to prostate cancer. Today, authorities such as the American Cancer Society, the National Cancer Institute, and the American Urological Association agree that the decision to get screened needs to be one that is taken after consideration of risks and benefits. In my own practice, I discuss each patient’s individual risk profile based on race, family history, overall health, weight, diet, and other factors so together we can make the decision if screening is necessary or beneficial.
One of these factors is the levels of a hormone called dihydrotestosterone, or DHT. DHT is a derivative of the most important male hormone, testosterone. An enzyme in the prostate converts testosterone to DHT. DHT has a much greater effect on the glandular cells of the prostate than regular testosterone. Normally, this acts like an amplifier in a stereo, increase the signaling power of testosterone. In BPH and prostate cancer, where the prostate cells are already overcharged, turning up the signal for growth even higher can have negative effects. Higher blood levels of DHT have been associated with increasing prostate size, but not with prostate cancer.
Strange as it may seem, estrogen is another hormone that can affect prostate cancer development and growth. Men produce a small amount of estrogen throughout their lives. The balance between estrogen and male hormones like testosterone is critical to maintain prostate health. As men age, though, the ratio between estrogen and male hormones shifts towards estrogen, changing the environment of the prostate.
By manipulating this hormonal environment, some scientists are trying to prevent prostate cancer development. Drugs that stop the conversion of testosterone to DHT are already used in treatment of BPH associated symptoms. They also are being investigated for prostate cancer prevention but the results have been mixed. These drugs have some serious side effects, which makes their widespread use require some caution.
The primary factors in the development of prostate cancer are family history, age, and race. These are obviously beyond the control of the individual person but there are some measures that the average man can take to lower his risk. For example, reducing dietary fat intake has a proven beneficial effect. The effects of dietary fat on the heart are well-known, but high levels of fat intake are also linked to faster-growing prostate tumors. Eating foods that are high in anti-oxidants may also reduce the chances of prostate cancer by reducing the damage done to DNA by free radicals. None of this guarantees prevention, but it can reduce the risks that are under your control.
When all is said and done, it is important to realize that more men die with prostate cancer than from prostate cancer. Keeping this in mind, talking with your doctor about issues like your individual risk of developing prostate cancer, need for and benefit of screening tests, and possible preventative steps is a wise idea.
Desmond Ebanks, MD is a board certified internal medicine physician specializing in age-management medicine; a science-based approach to preventive wellness, bioidentical hormone modulation and optimizing health at Alternity Healthcare, LLC in West Hartford, CT. He can be reached at 860-561-2294 or online at www.alternityhealthcare.com