Adverse Pathology Predicts Risk, Not Hormone Benefit in PCa
Key Takeaways
- In recurrent prostate cancer after prostatectomy, pooled evidence from five randomized phase 3 trials of postoperative radiotherapy suggested that higher adverse pathologic feature burden was associated with worse outcomes.
- Higher adverse feature counts did not significantly identify greater overall survival benefit from adding hormonal therapy to postoperative radiotherapy.
- Higher adverse feature counts also did not significantly identify greater metastasis-free survival benefit from adding hormonal therapy to postoperative radiotherapy.
- Categorical analyses, high-risk-subset analyses, and testing with a restricted score showed the same overall pattern.
- The authors concluded that conventional adverse pathology appeared prognostic rather than predictive of hormonal-therapy benefit after postoperative radiotherapy, a finding they said is clinically relevant for patients with pre-radiotherapy PSA ≤0.5 ng/ml.
In an individual patient data meta-analysis reported by Kishan et al in European Urology, investigators pooled five randomized phase 3 trials of postoperative radiotherapy with or without hormonal therapy, including 4,781 patients with a median follow-up of 9.1 years. They used intention-to-treat one-stage meta-analytic models to test whether pathologic burden modified hormonal-therapy benefit for overall survival (OS) and metastasis-free survival (MFS).
The adverse feature count was prospectively defined as a 0-4 sum of grade group 4-5 disease, seminal vesicle invasion, positive surgical margins, and extracapsular extension. A prespecified sensitivity analysis also tested a restricted 0-2 score that included only grade group 4-5 disease and seminal vesicle invasion.
Higher adverse feature count was independently prognostic for OS and MFS, indicating that worsening pathology tracked with poorer outcomes across the pooled cohort. Increasing adverse feature count did not significantly modify hormonal-therapy benefit for OS, with an interaction HR 0.93 (95% CI 0.79-1.10; p=0.4), or for MFS, with an interaction HR 0.88 (95% CI 0.77-1.01; p=0.08). The same overall pattern held when adverse feature count was analyzed categorically, examined in high-risk subsets, and retested with the restricted score.
Within the available evidence, conventional postoperative pathology separated men into worse and better prognostic groups but did not identify a different relative benefit from adding hormonal therapy to radiotherapy. The authors linked that conclusion to patients with pre-radiotherapy prostate-specific antigen (PSA) at or below 0.5 ng/ml.
The authors concluded that adverse pathological features after prostatectomy appeared prognostic rather than predictive of hormonal-therapy benefit with postoperative radiotherapy.
Clinician Questions
Does this prostate cancer analysis clearly apply only to men with PSA 0.5 ng/mL or lower before postoperative radiotherapy?
The conclusion was linked to men with recurrent prostate cancer who had pre-radiotherapy PSA at or below 0.5 ng/ml.
Did the lack of predictive value for adverse feature burden change in high-risk subsets or when the score was modeled differently?
The overall pattern remained similar when adverse feature count was analyzed categorically, examined in high-risk subsets, and retested with a prespecified restricted score based only on grade group 4-5 disease and seminal vesicle invasion.
What did prognostic rather than predictive mean for adverse pathology after prostatectomy in this postoperative radiotherapy analysis?
In this setting, higher adverse feature burden was associated with worse overall and metastasis-free outcomes, making it prognostic, but it did not identify greater relative benefit from adding hormonal therapy to postoperative radiotherapy, so it was not shown to be predictive.