The debate over the STAMPEDE and ENSA-RAD trials stems from a misunderstanding. They aren't contradictory but study different cohorts within the "high-risk" category. STAMPEDE focused on the highest-risk patients, while ENSA-RAD included a broader group. Combining their data could provide a more nuanced treatment approach.

While PSMA PET scans are more sensitive, they create a clinical dilemma because pivotal trials defining treatment efficacy were based on conventional imaging (CT/bone scans). This forces oncologists to either re-image patients with older technology to match trial criteria or make treatment decisions based on PET data that lacks a clear evidence-based framework for response assessment.

While the landmark EMBARK study enrolled patients with no metastatic disease on conventional imaging (CT/bone scan), a similar population scanned with advanced PSMA PET imaging showed 84% had M1 disease. This suggests that treatments for this population are effective against micrometastases not visible on older scans, blurring the lines between localized and metastatic states.

The patient population in pivotal trials like EMBARK, defined as non-metastatic by conventional imaging, is being re-evaluated. A UCLA study showed that over 80% of a similar patient group would have been positive on a PSMA PET scan, suggesting the "M0" classification is largely an artifact of older imaging technology and that these patients likely have micrometastatic disease.

Data from the CAPItello trial showed a significant number of patients with PTEN deficiency experienced radiological progression without a corresponding PSA increase. This challenges the standard reliance on PSA for monitoring in high-risk prostate cancer and suggests a need for more frequent, personalized imaging protocols to detect progression earlier.

New guidelines from an international working group are replacing patient-insensitive terms like "castration-resistant" with "Androgen Pathway Modulator (APM) resistant/naive." This modernizes language to encompass a broader range of therapies and improve patient communication, while also incorporating sensitive imaging like PSMA PET.

NCCN now recommends PSMA PET as a potential replacement for traditional CT, MRI, and bone scans for initial staging of higher-risk prostate cancer and detecting recurrence. This shift is based on PSMA PET's superior sensitivity and specificity for finding micrometastatic disease, positioning it as a more effective frontline tool.

Even when trials like LITESPARK 022 and Keynote 564 use identical eligibility criteria, outdated staging systems result in patient populations with different underlying risks. This makes direct comparison of outcomes between trials, even for the same drug, an unfair and statistically flawed analysis that ignores the function of a control arm.

The definition of high-volume disease, a key factor in chemotherapy decisions for prostate cancer, has changed across major trials like CHARTERED and STAMPEDE. This evolution, including variations in bone metastases counts and inclusion of Gleason score, complicates cross-trial analysis and highlights its weakness as a surrogate for true disease biology.