From the Guidelines
PSA screening is not recommended for average-risk men under 50, over 69, or with a life expectancy of less than 10-15 years due to the substantial harms associated with screening and treatment outweighing the potential benefits. The controversy surrounding Prostate-Specific Antigen (PSA) screening stems from its ability to detect prostate cancer early, but also its tendency to lead to overdiagnosis and overtreatment of slow-growing cancers that may not cause symptoms or death 1. The PSA test has a high false-positive rate, with approximately 70% of elevated results being false positives, leading to unnecessary biopsies and associated risks such as bleeding, infection, and pain 1.
Benefits and Harms of Screening
The benefits of PSA screening include the potential to detect prostate cancer early, which may improve treatment outcomes. However, the harms associated with screening and treatment, including overdiagnosis, overtreatment, and side effects from treatments like surgery or radiation, such as urinary incontinence and erectile dysfunction, cannot be ignored 1. The mortality benefit of PSA screening is modest, with studies suggesting that approximately 1,000 men need to be screened to prevent one prostate cancer death over 10 years 1.
Guidance for Screening
The American College of Physicians (ACP) recommends that clinicians inform men between the ages of 50 and 69 about the limited potential benefits and substantial harms of screening for prostate cancer, and base the decision to screen on the risk for prostate cancer, a discussion of the benefits and harms, the patient's general health and life expectancy, and patient preferences 1. Clinicians should not screen for prostate cancer using the PSA test in patients who do not express a clear preference for screening. For high-risk patients, such as those with a family history of prostate cancer, shared decision-making is also important, and information about the uncertainties, risks, and potential benefits associated with prostate cancer screening should be provided starting at age 45 1.
Frequency of Screening
There is currently no clear evidence to guide decisions about the frequency of screening, but increasing the interval between screening tests may reduce harms 1. The ERSPC trial, which screened men every 4 years, found a reduction in prostate cancer-specific mortality, suggesting that longer intervals may be indicated 1.
High-Value Care
Screening with the PSA test is considered low-value care, given that the chances of harm with screening outweigh the chances of benefit for most men, and the direct and indirect costs associated with biopsy, repeated testing, aggressive therapy, patient anxiety, and missed work are significant 1.
From the Research
Controversy Surrounding Prostate-Specific Antigen (PSA) Screening
The controversy surrounding PSA screening is multifaceted, with various factors contributing to the debate. Some of the key points include:
- Overdiagnosis and overtreatment: PSA screening can lead to the detection of slow-growing tumors that may not have caused symptoms or death, resulting in unnecessary biopsies and treatments 2, 3, 4, 5.
- Lack of sensitivity and specificity: PSA is not a perfect marker for prostate cancer, and its use can lead to false positives and false negatives 4, 5.
- Uncertainty about the benefits of screening: While some studies suggest that PSA screening can reduce mortality from prostate cancer, the overall benefit is modest, and it is unclear whether it outweighs the harms of overdetection and overtreatment 2, 3, 5, 6.
- Variability in guidelines: Different organizations have issued conflicting recommendations on PSA screening, with some advising against routine screening and others recommending shared decision-making between patients and clinicians 2, 3.
Limitations of PSA Screening
The limitations of PSA screening are well-documented, including:
- High proportion of overdiagnosis and overtreatment 2, 3, 4, 5.
- Potential harm to individuals, including unnecessary biopsies and treatments 2, 3, 4, 5.
- Lack of clarity on the definitive or best treatment for men diagnosed with localized prostate cancer 5.
Future Directions
Despite the controversy surrounding PSA screening, researchers are exploring new biomarkers and innovative methodologies to improve the limitations of traditional screening using PSA 3. Some of these new markers include: