PSA screening is key. This simple blood-test, properly interpreted and followed up, is an essential tool in cancer detection

Prostate health: PSA screening is key. This simple blood-test, properly interpreted and followed up, is an essential tool in cancer detection

It seems to be a rite of passage for men when they reach the age of 50–the word “prostate” starts cropping up with a dreary frequency. Of course, prostate problems can occur earlier than 50, and they may not appear at all. But 70 percent of prostate cancers occur in men 65 and older, and they generally develop without symptoms. So the half-century milestone marks the time when doctors begin the routine screening of male patients with a test for the prostate-specific antigen, or PSA. For those familiar with the digital rectal exam (DRE), the PSA test is a walk in the park–a mere blood test that may be done in conjunction with a test for cholesterol levels and other routine checks at the lab.

What’s PSA? What does it signify?

Prostate-specific antigen is a protein that’s manufactured by cells in the prostate gland. A certain amount of it can always be detected in a man’s bloodstream, but elevated levels can be a sign of prostate cancer. Thus, the PSA test becomes part of men’s lives when they reach the age of increased cancer risk. It’s important to note, however, that elevated PSA levels don’t necessarily mean cancer. Far from it: only 25 to 30 percent of men with high PSA numbers are diagnosed with cancer after a biopsy.

While PSA testing has long been an important diagnostic tool for urologists and cancer researchers, the meanings and interpretations of higher and lower PSA readings have been the subject of some debate in recent years. There are several reasons for this. First, non-cancerous prostate problems like benign prostatic hyperplasia, or BPH (the swelling of the prostate gland that’s very common in older men) as well as prostatitis (inflammation of the prostate) can often cause elevated PSA numbers. These numbers, if not carefully interpreted and related to other factors, can cause groundless worry over cancer, and worse, unnecessary invasive testing. Second, while in the past, PSA numbers were often interpreted in an absolute way, more recently doctors have come to a better understanding of the variance of normal PSA levels in individuals, and now place more weight on the velocity of change in a patient’s numbers than on the numbers themselves–although high readings are naturally enough a cause of greater concern.

“The ability to interpret has improved with new information related to PSA velocity,” says Robert E. Reiter, MD, professor of urology at UCLA’s Jonsson Comprehensive Cancer Center, “but we have also learned that PSA is a more difficult marker in some ways, in that cancers can be detected often in men with what we historically considered normal levels. So change over time is more important in general than absolute numbers.”

Timing and other types of test

If a man’s PSA numbers are considered normal, a once-a-year screening is appropriate, according to Dr. Reiter. If the numbers seem high, or are rising, he suggests a six-month interval. Again, it’s important to establish a baseline for individual patients, especially those with higher risk factors like a family history of prostate cancer, or established conditions of BPH or prostatitis. African-American men need to be especially careful, because their risk of prostate cancer is significantly higher. Ideally, a baseline for higher-risk men will have been established early, perhaps even by age 40.

An annual PSA test will generally be accompanied by that somewhat ignominious DRE, in which the doctor inserts a lubricated, gloved finger into the rectum and feels for any swelling and abnormality of the prostate through the rectal wall.

If the PSA test and/or the DRE turns up an abnormality or cause for concern, the doctor may decide to follow up with tests that assess the problem from several angles–simple urine and blood tests to check for kidney function and possible urinary tract infection; an ultrasound to get a better look at the prostate gland, bladder, and urethra; and possibly a biopsy of prostate tissue.

“The PSA test is an important test for early prostate cancer detection,” says Dr. Reiter, “but it’s still only one of many tests that are used and considered together.”

What if the news if bad?

If the PSA levels and other tests coalesce into a diagnosis of prostate cancer, there will be many options open to patient and physician, and here again, the PSA test is a valuable instrument in helping to determine how fast the cancer is growing, and thus how to treat it.

Prostate cancer generally develops very slowly, sometimes taking many years to reach a point where strong intervention is necessary to save the patient’s life. Obviously, the later it appears and the slower it develops, the better. For many older men with prostate cancer and no symptoms, the best treatment is no treatment at all. The doctor adopts a policy of “watchful waiting,” keeping tabs at regular intervals with PSA tests and DREs, and the patient doesn’t have to go through surgeries and other procedures that may cause incontinence, erectile dysfunction, and other complications.

In less favorable cases, with cancer appearing earlier or spreading more quickly, or both, those risks must be taken; however, there are still many treatment options, ranging from surgery (the earlier, the better for survival, according to recent studies) to radiation and radioactive seed implantation and hormone therapy. We can also expect advances in immunologic/biologic drug treatment in coming years.

Backing up the prostate

While PSA screening and regular doctor’s visits are vital for catching prostate problems early, it’s most important to take care of your whole body, which, after all, acts as a host to the gland in question. “A healthy lifestyle can help protect you from heart disease and a number of cancers,” says Dr. Reiter, “and those probably include prostate cancer. So healthy living is the paramount concern.”

What about vitamins and diet supplements? In an age of widespread experimentation with supplements, the prostate gland seems to have attracted more than its share–everything from extracts of the saw palmetto tree to lycopene, an antioxidant found in tomatoes and tomato-based foods. Saw palmetto may work in a similar way to the drug finasteride (Proscar), which is prescribed to help shrink the size of the prostate, improve urinary function in patients with BPH, and possibly ward off cancer. Saw palmetto products, however, aren’t well-regulated and, like other supplements, may contain a mix of ingredients that can do more harm than good.

“Not much is known about which substances promote prostate health,” says Dr. Reiter. “Lycopene, soy, green tea, vitamin E, and selenium have all been associated with a lesser risk of prostate cancer. We’re awaiting the results of the selenium and vitamin E studies now.”

If you’re interested in supplements, discuss brands and dosages with your doctor, and avoid heavy doses of anything, especially if it’s not found in a normal diet.

Meanwhile, regular doctor’s visits and PSA tests, in conjunction with a healthy lifestyle, will help keep cancer at bay. “If PSA numbers are elevated, it should be a cause for suspicion, but not fear,” says Dr. Reiter. “First, most men with elevated PSA do not have cancer. Second, most men with prostate cancer will not die from it.”

WHAT YOU CAN DO

* Overall good health, via exercise and a healthy diet, will be the best foundation for prostate care.

* One recent study has shown that men with higher levels of vitamin D in their blood have a lower incidence of prostate cancer. So get your exercise in the sun, which encourages the body to make vitamin D.

* Be wary of using popular supplements not found in a normal diet, pending the results of valid studies.

* If you have benign prostatic hyperplasia (BPH) ask your doctor whether you would benefit from a prescription of finasteride (Proscar).

* Remember, if you do develop prostate cancer, especially after age 65 or 70, the chances are that it will grow slowly and not be the cause of your death.

COPYRIGHT 2006 Belvoir Media Group, LLC

COPYRIGHT 2007 Gale Group