Prostate Cancer · Radiation · Locally advanced/high-risk localized disease
SPCG-7/SFUO-3
In locally advanced prostate cancer, does adding local radiotherapy to endocrine therapy reduce prostate-cancer mortality?
Absolute Effect
10-year prostate-cancer mortality
11.9% vs 23.9% (−12.0 points)
RR 0.44 (95% CI 0.30–0.66).
10-year overall mortality
29.6% vs 39.4% (−9.8 points)
RR 0.68 (95% CI 0.52–0.89).
Other outcomes
PSA recurrence was markedly lower with combined therapy: 25.9% versus 74.7% at 10 years. Urinary, rectal and sexual problems were somewhat more frequent after adding RT.
Clinical interpretation
This trial provides direct randomized evidence that local RT adds substantial disease-specific and overall survival benefit to endocrine therapy in locally advanced/high-risk localized prostate cancer.
The absolute mortality reduction is large enough to make the effect clinically tangible, while toxicity and treatment duration remain part of the trade-off.
NNT / NNH
At 10 years, NNT ≈ 9 to prevent one death from prostate cancer and ≈ 11 to prevent one death from any cause. A fixed-time NNH is not calculated because the pivotal report does not provide a single harmonized severe-toxicity endpoint.