Prostate Cancer Screening

A few weeks ago the local NBC affiliate promoted an area wide program of free prostate cancer screening. PSA (prostate specific antigen) testing was offered by the city’s two largest medical centers at no charge to all comers. So great was the zeal displayed by the commentators that I’m sure women would have been tested had they asked for the test. Our uncertainty regarding the effectiveness of prostate cancer screening is reflected in the comments listed below from major medical organizations concerned with the problem . Even the American Cancer Society which has the most aggressive approach to screening concedes that men at risk for the disease should first discuss the pros and cons of testing before undergoing it.

Obviously offering PSA testing to all comers does not allow for a serious discussion of the issue before undergoing screening. As is so often true, the desire to do good obliterates thought. Despite the uncertainty of prostate cancer screening it is being done on more men each year. Most of these men and their families are unaware of that screening is of unproven benefit. The are several new studies nearing completion which may resolve the issue.

The problem with prostate cancer screening is that we don’t know whether early treatment prevents death from the disease. The authors of the study in the Archives of Internal Medicine (see below) don’t think it does. Most urologists think it does. Does this make a difference? Yes. The treatment of prostate cancer has a high rate of serious complications. Depending on the treatment provided incontinence, impotence, and radiation bowel injury are common. This might not be too high a price to pay to save your life, but it certainly is if the treatment does not reduce the death rate from the disease.

Patients should talk to their doctor about the risks and benefits of undergoing prostate cancer screening before being tested. If their doctor doesn’t bring it up and just includes it as part of his clinical evaluation call him on it. Ask your doctor what tests he’s going to order before they’re done. If he won’t spend the time talking to you about the issue, get another doctor.

See below for more on prostate cancer screening

National Cancer Institute
Finding prostate cancer may not improve health or help a man live longer. Some cancers never cause symptoms or become life-threatening, but if found by a screening test, the cancer may be treated. It is not known if treatment of these cancers would help you live longer than if no treatment were given, and treatments for cancer may have serious side effects.
http://www.cancer.gov/cancertopics/pdq/screening/prostate/Patient/page4

There is still a lot of discussion about prostate cancer screening. Are the risks of not finding cancers (and giving men false reassurance) or side effects from tests greater than the benefits of screening? Will a screening programme using the tests we have at the moment reduce deaths from prostate cancer?
http://www.cancerhelp.org.uk/help/default.asp?page=2719#benefits

The US Preventive Services Tack Force found good evidence that PSA screening can detect early-stage prostate cancer but mixed and inconclusive evidence that early detection improves health outcomes. Screening is associated with important harms, including frequent false-positive results and unnecessary anxiety, biopsies, and potential complications of treatment of some cancers that may never have affected a patient’s health. The USPSTF concludes that evidence is insufficient to determine whether the benefits outweigh the harms for a screened population.
http://www.ahrq.gov/clinic/uspstf/uspsprca.htm

Prostate cancer is one of the most prevalent forms of cancer in men worldwide. Screening for prostate cancer requires diagnostic tests to be performed in the absence of any symptoms or indications of disease. These tests include the digital rectal examination (DRE), the prostate specific antigen (PSA) blood test and the transrectal ultrasound-guided biopsy (TRUS). Screening aims to identify cancers at an early and treatable stage, therefore increasing the chances of successful treatment while also maintaining a patient’s quality of life. This review identified two trials, consisting of 9,026 and 46,486 participants; however, neither was assessed to be of high quality. This review demonstrates that there is not enough high quality evidence to inform whether or not screening for prostate cancer, via either a DRE, PSA or TRUS biopsy, is more effective than no screening in reducing the number of deaths attributable to prostate cancer. The effects of screening upon quality of life and cost have not been researched in randomised controlled trials. The results from two large trials, to be completed in the next few years, will provide greater information on this issue.
Ilic D, O’Connor D, Green S, Wilt T. Screening for prostate cancer. Cochrane Database of Systematic Reviews 2006, Issue 3. Art. No.: CD004720. DOI: 10.1002/14651858.CD004720.pub2
http://www.cochrane.org/reviews/en/ab004720.html

American Cancer Society
Both the prostate-specific antigen (PSA) blood test and digital rectal examination (DRE) should be offered annually, beginning at age 50, to men who have at least a 10-year life expectancy. Men at high risk (African-American men and men with a strong family of one or more first-degree relatives [father, brothers] diagnosed before age 65) should begin testing at age 45. Men at even higher risk, due to multiple first-degree relatives affected at an early age, could begin testing at age 40. Depending on the results of this initial test, no further testing might be needed until age 45.
Information should be provided to all men about what is known and what is uncertain about the benefits, limitations, and harms of early detection and treatment of prostate cancer so that they can make an informed decision about testing.
Men who ask their doctor to make the decision on their behalf should be tested. Discouraging testing is not appropriate. Also, not offering testing is not appropriate.
http://www.cancer.org/docroot/PED/content/PED_2_3X_ACS_Cancer_Detection_Guidelines_36.asp

[T]here is no unanimous opinion in the medical community regarding the benefits of prostate cancer screening. Those who advocate regular screening believe that finding and treating prostate cancer early offers men more treatment options with potentially fewer side effects. Those who recommend against regular screening note that because most prostate cancers grow very slowly, the side effects of treatment would likely outweigh any benefit that might be derived from detecting the cancer at a stage when it is unlikely to cause problems. Because a decision of whether to be screened for prostate cancer is a personal decision, it’s important that each man talk with his doctor about whether prostate cancer screening is right for him.
http://www.prostatecancerfoundation.org/site/c.itIWK2OSG/b.47285/k.CCF1/Detection__Screening.htm

A benefit of screening was not found in our primary analysis assessing PSA screening and all-cause mortality (adjusted odds ratio, 1.08; 95% confidence interval, 0.71-1.64; P = .72), nor in a secondary analysis of PSA and/or DRE screening and cause-specific mortality (adjusted odds ratio, 1.13; 95% confidence interval, 0.63-2.06; P = .68).
These results do not suggest that screening with PSA or DRE is effective in reducing mortality. Recommendations for obtaining “verbal informed consent” from men regarding such screening should continue.
Arch Intern Med. 2006;166:38-43.
http://archinte.ama-assn.org/cgi/content/abstract/166/1/38

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