Top Line: Do PSA changes predict survival outcomes in patients with very high risk or metastatic prostate cancer?
The Study: PSA nadir has long served as shorthand for “responding well” in advanced prostate cancer, but interpreting PSA across very different baseline disease burdens can feel more art than science. This post-hoc analysis pooled 7129 patients from five phase 3 trials within the STAMPEDE platform (62% metastatic, 38% very high risk nonmetastatic). Treatment arms included ADT alone, ADT + docetaxel, ADT + abiraterone ± enzalutamide, or ADT + prostate radiotherapy in metastatic disease. Landmark analyses at 6, 12, and 24 weeks evaluated PSA categories (≤0.2, >0.2–1.0, >1.0–3.0, >3.0) against OS at 96 months, stratified by CHAARTED metastatic volume or nodal status. PSA ≤0.2 at 6 or 12 weeks predicted survival just as good as the same threshold at 24 weeks meaning early responders fared just as well as the textbook 24-week responders. We've previously seen that adding abiraterone improves OS across the advanced disease spectrum, and here that finding gets a useful refinement. Among patients on an abiraterone regimen who hit PSA ≤0.2 at 24 weeks, 96-month OS varied dramatically by baseline burden. It was 82.8% for non-metastatic node-negative, 79.4% for non-metastatic node-positive, 64.1% for low-volume metastatic, and just 44.6% for high-volume metastatic. The authors hypothesize that high-volume disease may harbor a larger burden of residual non-PSA-secreting tumor despite apparent biochemical success.
TBL: The “perfect” PSA response on ADT/ARPI has very different prognostic meaning depending on the initial extent of disease with high volume metastatic disease carrying a nearly 50% risk of mortality at 8 years even with an initial PSA nadir <0.2. | Kayani, Lancet Oncol 2026
The Study: PSA nadir has long served as shorthand for “responding well” in advanced prostate cancer, but interpreting PSA across very different baseline disease burdens can feel more art than science. This post-hoc analysis pooled 7129 patients from five phase 3 trials within the STAMPEDE platform (62% metastatic, 38% very high risk nonmetastatic). Treatment arms included ADT alone, ADT + docetaxel, ADT + abiraterone ± enzalutamide, or ADT + prostate radiotherapy in metastatic disease. Landmark analyses at 6, 12, and 24 weeks evaluated PSA categories (≤0.2, >0.2–1.0, >1.0–3.0, >3.0) against OS at 96 months, stratified by CHAARTED metastatic volume or nodal status. PSA ≤0.2 at 6 or 12 weeks predicted survival just as good as the same threshold at 24 weeks meaning early responders fared just as well as the textbook 24-week responders. We've previously seen that adding abiraterone improves OS across the advanced disease spectrum, and here that finding gets a useful refinement. Among patients on an abiraterone regimen who hit PSA ≤0.2 at 24 weeks, 96-month OS varied dramatically by baseline burden. It was 82.8% for non-metastatic node-negative, 79.4% for non-metastatic node-positive, 64.1% for low-volume metastatic, and just 44.6% for high-volume metastatic. The authors hypothesize that high-volume disease may harbor a larger burden of residual non-PSA-secreting tumor despite apparent biochemical success.
TBL: The “perfect” PSA response on ADT/ARPI has very different prognostic meaning depending on the initial extent of disease with high volume metastatic disease carrying a nearly 50% risk of mortality at 8 years even with an initial PSA nadir <0.2. | Kayani, Lancet Oncol 2026