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Biochemical relapse after radical radiotherapy for prostate cancer — MSRA MCQ

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HardPSABiochemical relapse after radical radiotherapy for prostate cancerMSRA

A 69-year-old man is followed up after radical external-beam radiotherapy with 18 months of androgen deprivation therapy for CPG 4 localised prostate cancer. His PSA nadir was 0.3 ng/mL. Using the same assay, PSA has risen to 0.7 ng/mL 4 months ago and 1.1 ng/mL today. He has no bone pain, weight loss, new urinary symptoms or neurological symptoms. He is fit enough to consider radical salvage treatment if appropriate. He asks whether he should start hormone therapy immediately. He has not entered a clinical trial. What is the most appropriate next management step?

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Correct answer: A — Repeat PSA surveillance to permit calculation of PSA doubling time from at least 3 measurements over at least 6 months before changing treatment

This is a rising PSA after radical radiotherapy, but PSA rise alone should not trigger an immediate treatment change. In particular, PSA doubling time should be estimated using at least 3 PSA measurements obtained over at least 6 months. This patient has only two post-nadir rising values across 4 months, so the minimum dataset has not yet been obtained. Immediate androgen deprivation therapy is not routinely indicated for biochemical relapse without symptomatic local progression, proven metastases or a PSA doubling time below 3 months. A prostate biopsy after radiotherapy is restricted to people being considered for local salvage therapy in a clinical trial; this patient is not in such a trial. Routine MRI before salvage radiotherapy is not recommended. Isotope bone scanning is appropriate when symptoms or PSA trends suggest metastases, neither of which is present here. The priority is therefore further standardised serial PSA measurement, enabling risk stratification by PSA kinetics before committing him to systemic or local salvage treatment.

Reference: NICE NG131: Prostate cancer: diagnosis and management, managing relapse after radical treatment (2019; checked August 2026) — https://www.nice.org.uk/guidance/ng131/chapter/Recommendations NICE NG131: Prostate cancer: diagnosis and management, managing relapse after radical treatment (2019; checked August 2026) — https://www.nice.org.uk/guidance/ng131/chapter/Recommendations NICE NG131: Prostate cancer: diagnosis and management, managing relapse after radical treatment (2019; checked August 2026) — https://www.nice.org.uk/guidance/ng131/chapter/Recommendations