ProtecT

Clinical question

For localized prostate cancer, what are the long-term trade-offs between monitoring, surgery and radiotherapy?

Trial context

Population

1,643 men with clinically localized prostate cancer

Intervention

Active monitoring vs prostatectomy vs radiotherapy

Key endpoint

Metastatic disease at 15 years

Time horizon / follow-up

15 years

Absolute Effect

What changes for patients?

At 15 years, prostate-cancer mortality was low and similar: 2.2% prostatectomy, 2.9% RT and 3.1% active monitoring. Metastases were less frequent after prostatectomy or RT than monitoring: 4.7%, 5.0% and 9.4%, respectively. NNT 21 refers specifically to prostatectomy vs monitoring for preventing one metastasis by 15 years, not death.

NNT: 21 for prostatectomy vs monitoring

Treatment burden / harm

Treatment morbidity

NNH: Not quantifiable from the selected endpoint; urinary, sexual and bowel harms reported separately

Relative effect

HR: No significant difference in prostate-cancer mortality; metastases 4.7% vs 9.4% for prostatectomy vs monitoring

Cancer-specific mortality P=.53 overall

Clinical interpretation

At 15 years, prostate-cancer mortality remained low across ProtecT arms, but active monitoring led to more progression and metastases than surgery or radiotherapy.

Primary publication

Hamdy FC, et al. N Engl J Med. 2023;388:1547–1558.
Primary publication / source

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ProtecT

For localized prostate cancer, what are the long-term trade-offs between monitoring, surgery and radiotherapy?

What changes for patients?

Current-practice context · reviewed 14 October 2026