A narrative PubMed review identified 45 non-cancer PSA confounders—30 that can raise PSA and 15 that can lower it—showing how easily frontline interpretation can drift toward false positives, false reassurance, or unnecessary biopsy. For NPs and PAs, that makes your pre-biopsy history, medication reconciliation, and timing judgment not “support work,” but the clinical pivot that can prevent avoidable imaging, procedures, and missed malignancy.

Why It Matters To Your Practice

• PSA is not a stand-alone cancer signal: infection, inflammation, urinary retention, ejaculation, prostate stimulation, instrumentation, systemic inflammatory states, medications, lifestyle factors, and even lab variability can shift the number.

• The review found assay and inter-lab differences alone may exceed 20%, meaning a “change” in PSA may reflect testing conditions rather than disease biology.

• You are often the last clinician to catch these details before a urology referral or biopsy decision, which puts NPs and PAs at the center of better risk stratification.

Clinical Benefits

• A structured pretest questionnaire can uncover transient PSA elevators and medication-related PSA suppressors before acting on a single result.

• Repeat testing after reversible triggers resolve may improve specificity and reduce unnecessary MRI, referral escalation, and biopsy.

• Common PSA-lowering agents in the review included 5-alpha-reductase inhibitors, NSAIDs, statins, thiazide diuretics, and metformin—key medication-history wins that advanced practice clinicians are especially good at catching.

Managing Risks

• Watch for false-positive drivers such as prostatitis, urinary infection, retention, recent ejaculation, recent manipulation, or recent instrumentation.

• Watch for false-negative or deceptively lower PSA values in patients taking PSA-lowering medications or with lifestyle factors that may suppress levels.

• When possible, standardize timing and use the same assay/lab for repeat testing to reduce analytic noise before escalating to biopsy.

The Bottom Line

• This review’s message is simple: before biopsy, check the confounders.

• Your careful history, med review, and decision to repeat or standardize testing can be the difference between unnecessary procedures and smarter cancer detection.

• That is frontline diagnostic stewardship—and it is exactly where NPs and PAs lead.

Reference: Non-Prostate Cancer-Related Factors That Influence Serum Prostate-Specific Antigen: A Narrative Review of 45 Non-Malignant PSA Modifiers.