From the Guidelines
Normal PSA levels generally range from 0 to 4 nanograms per milliliter (ng/mL) of blood, though what's considered normal varies with age. For men in their 40s, levels below 2.5 ng/mL are typical, while men in their 50s may have levels up to 3.5 ng/mL. Men in their 60s and 70s often have slightly higher baseline levels. It's essential to understand that PSA levels naturally increase with age as the prostate enlarges. While elevated PSA can indicate prostate cancer, many benign conditions like prostatitis (inflammation), benign prostatic hyperplasia (BPH), or recent ejaculation can also raise PSA temporarily.
Regular monitoring of PSA trends over time, rather than a single measurement, provides more valuable information. Any significant rise in PSA levels (particularly if it increases by more than 0.75 ng/mL per year) should prompt further evaluation by a healthcare provider, regardless of whether the absolute value falls within the "normal" range. According to the study by 1, PSA is not a cancer-specific marker, and therefore most men with elevated PSA levels do not have prostate cancer.
Some key points to consider when evaluating PSA levels include:
- PSA levels can be affected by various factors, including age, race, and family history 1
- The American Cancer Society recommends that men at average risk for prostate cancer should have a PSA level of 4.0 ng/mL or higher to recommend referral for further evaluation or biopsy 1
- For men whose PSA is less than 2.5 ng/mL, screening intervals can be extended to every 2 years, and screening should be conducted yearly for men whose PSA level is 2.5 ng/mL or higher 1
- A prior negative biopsy lowers the risk of prostate cancer, and methods are available to merge this information to achieve an estimate of a man’s overall risk of prostate cancer and, more specifically, of his risk of high-grade prostate cancer 1
It's crucial to individualize the decision to screen for prostate cancer, considering patient preferences and risk profile, as recommended by 1. Men should be informed of the gaps in the evidence and assisted in considering their personal preferences and risk profile before deciding whether to be tested.
From the Research
Normal PSA Levels
PSA (Prostate-Specific Antigen) levels are used to screen for prostate cancer and monitor treatment. The normal range for PSA levels can vary depending on age and other factors.
- A study published in 2005 2 suggested that a PSA level of 2.5 ng/mL may be a more appropriate cutpoint for determining the need for prostate biopsy, as the prostate cancer detection rate for a PSA level between 2.5 and 4.0 ng/mL was similar to that for the PSA range of 4.0 to 10.0 ng/mL.
- Another study published in 2023 3 found that baseline PSA levels can guide decisions on repeat screening intervals, and a baseline PSA of <1.0 ng/mL for men aged 55-69 years is a strong indicator to delay or stop further screening.
- The European Association of Urology guidelines recommend a risk-based strategy for prostate cancer screening based on the first prostate-specific antigen (PSA) level and age 3.
Factors Affecting PSA Levels
Several factors can affect PSA levels, including:
- Age: PSA levels tend to increase with age 3
- Prostate size: Larger prostates can produce more PSA 4
- Medications: Certain medications, such as 5-alpha-reductase inhibitors (5ARIs), can lower PSA levels 5, 6
- Digital rectal examination (DRE): A DRE can cause a temporary increase in PSA levels 3
Interpretation of PSA Results
PSA results should be interpreted in conjunction with other factors, such as: