From the Guidelines
PSA levels between 4-10 ng/mL indicate about a 25% chance of prostate cancer, while levels above 10 ng/mL suggest a greater than 50% chance, but the decision to proceed to prostate biopsy should be based on individualized risk assessment considering multiple factors, including free and total PSA, patient age, PSA velocity, PSA density, family history, ethnicity, prior biopsy history, and comorbidities 1.
Key Points to Consider
- PSA is not a cancer-specific marker, and most men with elevated PSA levels do not have prostate cancer 1.
- A total PSA level of 4.0 ng/mL has traditionally been used as the threshold for considering a prostate biopsy, but recent studies suggest that a substantial number of men with PSA levels between 2.5 and 4.0 ng/mL will have prostate cancers on biopsy 1.
- The American Cancer Society recommends individualized risk assessment for men with PSA levels between 2.5 ng/mL and 4.0 ng/mL, considering other risk factors for prostate cancer, particularly for high-grade cancer 1.
- The decision to proceed to prostate biopsy should take into account multiple factors, including free and total PSA, patient age, PSA velocity, PSA density, family history, ethnicity, prior biopsy history, and comorbidities 1.
Important Considerations for PSA Testing
- PSA testing is recommended for men over 50, or earlier for those with risk factors, though screening guidelines vary and should be discussed with a healthcare provider to weigh the benefits and potential harms of testing.
- Rising PSA levels after treatment may indicate cancer recurrence, while successful treatment typically results in very low or undetectable PSA levels.
- Individualized risk assessment based on a variety of risk factors may be a more appropriate way to characterize the risk of prostate cancer, rather than relying on a single PSA threshold value 1.
From the Research
Prostate-Specific Antigen (PSA) and Cancer
- PSA is a protein produced by the prostate gland, and elevated levels can indicate prostate cancer 2.
- A PSA level of less than 10 ng/mL is often considered low-risk for prostate cancer, and active surveillance may be recommended for men with a Gleason score of 6 or less and a PSA level of less than 10 ng/mL 2.
- Fluctuations in PSA levels can be associated with an increased risk of developing prostate cancer, with a significant increase in risk observed in patients with increasing PSA levels 3.
Digital Rectal Examination (DRE) and PSA
- DRE is a part of the clinical evaluation of men on active surveillance for prostate cancer, and can be used to predict the presence of clinically significant prostate cancer (csPCa) 4.
- A suspicious DRE can be a predictor of csPCa, particularly if the DRE at diagnosis was negative 4.
- The combination of DRE and PSA can provide valuable information for diagnosing csPCa, with a positive DRE having 21.8% sensitivity and 91.3% specificity for CSPC 5.
PSA Variability and Prostate Cancer Risk
- An increase in PSA levels can be associated with an increased risk of developing prostate cancer, with a significant increase in risk observed in patients with PSA levels < 4 ng/mL and an increase in PSA level of approximately 20% 3.
- A decrease in PSA levels can be associated with a reduced risk of developing prostate cancer, with a significant reduction in risk observed in patients with PSA levels of 4 ng/mL or higher and a decrease in PSA level of approximately 20% 3.
Active Surveillance and PSA
- Active surveillance is a conservative management approach for men with low-risk prostate cancer, which involves close monitoring with digital rectal examination, periodic biopsy, and serial PSA testing 2, 6.
- The goal of active surveillance is to avoid long-term adverse effects on the patient's quality of life, while still monitoring for any signs of disease progression 2, 6.
- PSA levels are an important factor in determining the frequency of monitoring and the need for intervention in men on active surveillance 2, 6.