Discomforting News About the Test for Prostate Cancer
IF YOU'RE a man, the number 4 is important to you. A 4 or lower is what doctors have considered normal for a test that screens for prostate cancer, the most common cancer among American men.
The test is called the prostate-specific antigen (PSA) test. It measures how much of a certain protein produced by the prostate--a walnut-sized gland that helps produce the milky semen necessary for carrying sperm--is circulating in the bloodstream. A PSA level between 4 and 10 (nanograms of protein per milliliter of blood) is considered slightly elevated; 10 to 20, moderately elevated; and greater than 20, highly elevated. The higher the number, the greater the chance that cancer might be present. (As the prostate gland gets bigger, say, from a tumor, the PSA level tends to rise.) The number 4 or lower, on the other hand, has generally been considered a stamp of good prostate health. Until now.
Results from a new study suggest that with 4 as a cut-off point, a surprising 82 percent of prostate cancers are missed in men under the age of 60. The results are so stunning that Rinaa Punglia, MD, principal investigator of the Harvard medical team that conducted the study, feels the guideline for normal levels should be lowered to 2.6, which would help flag more tumors at an early stage.
But lowering the PSA guideline poses some problems of its own. When you hit the red-flag number, whatever it may be, you need to undergo an invasive prostate biopsy as the next step in the screening process. That's because the PSA test doesn't nail a cancer diagnosis on its own. A high number may also indicate benign, non-cancerous conditions, such as prostate inflammation (prostatitis) or prostate enlargement, known as benign prostatic hyperplasia. You need the biopsy to be sure.
While more biopsies triggered by lower PSAs would catch more cancers, they would also needlessly subject many more men to the uncomfortable biopsy procedure, which involves removal of a sample of the prostate tissue with a small needle and poses a slight risk of bleeding and infection. Consider that the overwhelming majority of biopsies do not reveal prostate cancer but, instead, one of the benign prostate conditions.
Even with the extra cancer cases that would be detected through the greater number of biopsies triggered by a lower PSA threshold, some doctors are concerned about overdiagnosis and overtreatment. Men who have prostate cancer often live for decades and die of something else before the tumor has ever had a chance to cause any real problems. If the tumor is treated unnecessarily, it can lead to complications such as impotence and incontinence.
Of course, on the other hand, underdiagnosis can be deadly. Some 220,000 new cases are currently diagnosed annually, with more than one in 10 of them resulting in eventual death.
Given the pros and cons about which PSA level--4 or 2.6--makes a better biopsy cut-off point, what is the best choice? Ultimately, it comes down to a personal decision made by you in conjunction with your doctor, based on your own medical history and other risk factors.
In any event, the American Cancer Society recommends that prostate cancer screening begin at age 50 for men without serious cancer risk and a life expectancy of at least 10 years. Men with high risk (see "Protecting Yourself Through Lifestyle," at left) should begin screening at age 45. Screening tests include not only the PSA test but also the digital rectal exam, during which the doctor directly feels for physical abnormalities.
In some cases, a transrectal ultrasound is called for. A small probe is inserted into the rectum and produces sound waves to generate a picture of the prostate gland.
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Protecting Yourself Through Lifestyle
While researchers and physicians debate the best PSA cut-off point for helping to identify prostate cancer, they agree that personal history, diet, and other aspects of lifestyle influence its development. Here are some things you can do to prevent the disease.
• Pay attention to risk factors, and screen accordingly. The primary risk factors for developing prostate cancer include age (55 or older); a family history of the disease; African-American heritage; chronic intake of a high-fat/low-fiber diet; and incidence of sexually transmitted diseases. If you have one or more of these factors, check with your doctor to discuss whether your screening efforts should be more intense than a yearly digital rectal exam and PSA test.
• Avoid excessive intake of animal fats and meats. Studies have shown that a high animal fat intake-especially from red meat-is linked to an increased risk for prostate cancer.
• You've heard it before-eat lots of fruits and vegetables. Numerous studies have suggested that eating a primarily plant-based diet with a wide variety of fruits and vegetables, including cruciferous vegetables like broccoli, cabbage, and cauliflower, provides a hedge against many types of cancer-including prostate cancer. Scientists are now starting to identify which substances in produce may be beneficial. But the research is too preliminary at this point to recommend supplements with particular compounds. Eat whole fruits and vegetables to obtain maximum benefits.
Did you know...
People pour more into-and drink more out of-short, wide glasses than tall, narrow ones that hold the same volume.