How soon after prostatectomy should PSA be tested to detect biochemical recurrence?
Executive summary
After radical prostatectomy, PSA is expected to fall to undetectable levels within weeks to months, and guidelines generally advise the first postoperative PSA check at about 6–8 weeks; thereafter most expert guidance recommends frequent surveillance (every 3–6 months or every 6 months) during the first 3–5 years when biochemical recurrence (BCR) risk is highest, then annual testing if stable—these intervals aim to detect a rising PSA early enough to guide salvage therapy and imaging decisions [1] [2] [3] [4].
1. Why timing matters: the biology and clinical stakes
PSA after prostatectomy typically declines to undetectable values within a couple of months, and a detectable or rising PSA can precede clinical metastasis by years, so timing tests to distinguish transient low-level detectability from true biochemical recurrence is important because early detection can enable potentially curative salvage radiation or other interventions [1] [5] [6].
2. First postoperative PSA: wait 6–8 weeks, then act on trends not single numbers
Clinical authorities commonly recommend waiting at least 6–8 weeks after surgery before the first PSA because residual circulating PSA can persist for weeks after tissue removal; a single low detectable value early on does not automatically equal recurrence and should be interpreted in the context of follow-up measurements and risk features [1] [7].
3. The surveillance rhythm: more frequent early checks, then relax if stable
Most guidelines and recent studies advise closer PSA monitoring in the early years—every 3–6 months or every 6 months for roughly the first 3–5 years—because the hazard of BCR is highest in that interval; after about three years many recommend moving to annual testing if PSA remains undetectable and the patient is low risk, though evidence for exact intervals is limited and evolving [3] [2] [4].
4. What defines recurrence and when to investigate further
Biochemical recurrence after prostatectomy is most commonly defined as a confirmed PSA ≥0.2 ng/mL (with a subsequent confirmatory rise) in many European and clinical series, but lower thresholds and ultrasensitive assays are used in research and may detect earlier rises; decisions to image (for example PSMA PET) or to start salvage therapy also incorporate PSA kinetics, doubling time, pathologic grade and margins, not PSA level alone [6] [8] [9] [10].
5. Risk stratification changes timing and urgency
Patients with high‑risk features—short interval to recurrence (<2 years), PSA doubling time ≤1 year, or Grade Group 4–5 disease—are at greater risk of progression and typically prompt earlier imaging and consideration of salvage treatment when PSA rises, whereas patients with long PSA doubling times (>15 months) may be managed less aggressively; guidelines and consensus panels use these risk elements to tailor testing and action thresholds [10] [4] [7].
6. Practical takeaways and limits of the evidence
In practice, assay the first PSA at about 6–8 weeks after prostatectomy, then monitor every 3–6 months (or every 6 months per some guidelines) for the first 3 years and annually thereafter if stable—escalate testing frequency, obtain PSMA PET, and consider salvage therapy sooner for confirmed rises to ≥0.2 ng/mL or for rapidly rising PSA or adverse pathology; however, the exact best interval is imperfectly studied and recommendations balance early detection with overtesting and depend on individual risk [1] [3] [2] [10] [4].