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.
The LUNAR trial's positive outcome was unexpected. Patients received SBRT for all PET-visible lesions, meaning the added Lutetium-PSMA was targeting disease that couldn't be seen. This implies the radioligand can effectively bind to and treat microscopic cancer cells, challenging the notion it only works on clearly imaged tumors.
Advanced biomarkers are no longer just research tools. Tools like Decipher provide results within a week from a shipped sample, and Artera's MMEI simply requires scanning a pathology slide. This practicality allows clinicians to personalize treatment intensification for high-risk patients in current clinical workflows, moving beyond purely clinical risk factors.
The clinical definition of "high-risk" prostate cancer is evolving due to improved diagnostics. The move from digital rectal exams to more sensitive MRI for T-staging means more patients meet the criteria for being high-risk. This "stage migration" makes it challenging to apply findings from older clinical trials to a contemporary patient population.
Expert analysis reveals a key weakness in many Lutetium-PSMA trials: the choice of the control arm. By comparing the novel therapy against a less-than-optimal standard of care, the trials may have been designed for an "easy win," dampening expert enthusiasm and raising questions about its true superiority over other potent hormonal therapies.
While ideally a PSMA PET scan would be used early in biochemical relapse, practical limitations like long wait times force a pragmatic approach. Clinicians delay scans until PSA levels are higher (e.g., >0.5) to increase the probability of a positive, actionable result, thereby conserving limited "PET slots" for patients where the scan will most likely change management.