What Are the Benefits and Harms of Screening?
Dr. Alex Krist, vice chair of the U.S. Preventive Services Task Force, provides an overview of the Task Force’s prostate cancer screening recommendation in this video.
The U.S. Preventive Services Task Force (Task Force) is an organization made up of doctors and disease experts who look at research on the best way to prevent diseases and make recommendations on how doctors can help patients avoid diseases or find them early.
The Task Force made the following recommendations about prostate cancer screening—
- Men who are 55 to 69 years old should make individual decisions about being screened for prostate cancer with a prostate specific antigen (PSA) test.
- Before making a decision, men should talk to their doctor about the benefits and harms of screening for prostate cancer, including the benefits and harms of other tests and treatment.
- Men who are 70 years old and older should not be screened for prostate cancer routinely.
The goal of screening for prostate cancer is to find cancers that may be at high risk for spreading if not treated, and to find them early before they spread. However, most prostate cancers grow slowly or not at all.
Possible Benefits of Screening
The benefits of screening for prostate cancer may include—
- Finding prostate cancers that may be at high risk of spreading, so that they can be treated before they spread. This may lower the chance of death from prostate cancer in some men.
- Some men prefer to know if they have prostate cancer.
- For every 1,000 men between the ages of 55 and 69 years old who are screened, about 1 death will be prevented, and 3 men will be prevented from getting prostate cancer that spreads to other places in the body.
- Many men with prostate cancer never experience symptoms and, without screening, would never know they had the disease.
The possible harms of screening for prostate cancer include harms from screening, diagnosis, and treatment.
Possible Harm from Screening
False positive test results: This occurs when a man has an abnormal PSA test but does not have prostate cancer. False positive test results often lead to unnecessary tests, like a biopsy of the prostate. They may cause men to worry about their health. Older men are more likely to have false positive test results.
Possible Harms from Diagnosis
Screening finds prostate cancer in some men who would never have had symptoms from their cancer in their lifetime. Treatment of men who would not have had symptoms or died from prostate cancer can cause them to have complications from treatment, but not benefit from treatment. This is called overdiagnosis.
Prostate cancer is diagnosed with a prostate biopsy. A biopsy is when a small piece of tissue is removed from the prostate and looked at under a microscope to see if there are cancer cells. Older men are more likely to have a complication after a prostate biopsy.
A prostate biopsy can cause—
- Blood in the semen or ejaculate.
Possible Harms from Treatment
Before 2010, common treatments to cure prostate cancer included surgery to remove the prostate and radiation therapy. Since about 2010, more men have received active surveillance (closely monitoring the prostate cancer to see if it grows before treating it).
The most common harms from prostate cancer treatment are—
- Urinary incontinence (accidental leakage of urine). About 1 out of every 5 men who have surgery to remove the prostate loses bladder control.
- Erectile dysfunction (impotence). About 2 out of every 3 men who have surgery to remove the prostate become impotent, and about half of men who receive radiation therapy become impotent.
- Bowel problems, including fecal incontinence (accidental leakage of bowel movements) and urgency (sudden and uncontrollable urge to have a bowel movement). About 1 out of every 6 men who has radiation therapy has bowel problems.
With funding from CDC, the American College of Preventive Medicine developed materials that enhance informed decision making for men considering prostate cancer screening. The patient Decision Guide helps men decide if prostate cancer screening is right for them. The Provider Guide helps prepare primary care physicians for discussions with patients.