It has long been conventional wisdom in modern medicine that early cancer screening saves lives. While screening for some cancers can indeed save lives, there's a growing body of research that shows it can also be harmful.
This is the case with screening for prostate cancer, one of the most common types of cancer in men. As a family physician, I see a lot of middle-aged and older men who ask me if they should be screened for cancer of the prostate.
Here's my usual advice: If you're not experiencing any symptoms -- such as difficulty urinating, pain during urination or going frequently -- then don't get screened. On the other hand, if you're experiencing symptoms, then get tested. Let me explain why.
Recent studies show that only 1 in 1,000 people are saved as a result of prostate-cancer screening (just to be clear, "screening" refers specifically to testing of patients without symptoms). In fact, nonsymptomatic people are much more likely to suffer health problems as a result of further testing and treatment than they are to benefit from early screening.
One problem is that the test used to detect prostate cancer, the prostate-specific antigen (PSA) test, can produce misleading results. This test measures the amount of PSA in the blood. Elevated PSA levels can indicate the presence of cancer -- or, as is often the case, they may not.
Many men over age 50 have elevated PSA levels for benign reasons other than prostate cancer. According to the Mayo Clinic, only about one in four men with a positive PSA test turns out to have prostate cancer.
In order to confirm a cancer diagnosis following a positive PSA test, a doctor must perform a biopsy. Prostate biopsies are usually safe procedures, but they can still cause complications, such as infections that can be difficult to treat.
Now let's say a prostate biopsy does indeed find cancer. The PSA test may have just saved your life, right? Not so fast. The biopsy results won't necessarily reveal whether the cancer found is likely to kill you or not. Prostate cancer is usually slow-growing, and most men diagnosed with it won't don't die from it, even if nothing is done.
Because of the relatively low mortality rate, over-treatment is a real risk following a positive biopsy. Radiation treatment or surgically removing the prostate can both have serious side effects, including incontinence and impotence.
One key indicator of whether the cancer present is of the more aggressive and potentially lethal variety is whether the patient is suffering from symptoms like the ones I mentioned earlier. But when there are no symptoms, the "cure" is likely more harmful than the disease.
That's why the American Urological Association's latest guidelines say screening should be done only in men between the ages of 55-69, and only if it has been discussed with the patient that the risk of harm exceeds the benefit of preventing cancer.
Other medical groups, including the United States Preventive Services Task Force and the American Academy of Family Physicians, now simply advise that screening not be done at all.
If you've been thinking about getting screened for prostate cancer, discuss your options with your doctor and remember -- getting screened probably won't lead to a better health outcome.
Dr. Craig Desoer is a family physician at Contra Costa Regional Medical Center & Health Centers. Healthy Outlook is written by the professional staff of Contra Costa Health Services, the county health department. Send questions to series coordinator Dr. David Pepper at firstname.lastname@example.org. For more health information, go to www.cchealth.org.