[ 68 Ga]Ga‐PSMA‐11 PET/CT for baseline staging of high‐risk prostate cancer: A real‐world study
Amy Rose Sharkey, Paul Bassett, Manil Subesinghe, Gurdip Azad, Ajay Aggarwal, Simon Hughes, Prokar Dasgupta, Rick Popert, Ben Challacombe, Gary J. R. CookAbstract
Objective
To use real‐world data to determine the clinical risk factors that are predictive of metastatic disease in high‐risk prostate cancer (PCa) patients undergoing staging [ 68 Ga]Ga‐Prostate‐Specific Membrane Antigen (PSMA)‐11 positron emission tomography combined with computed tomography (PET/CT).
Methods
Subjects with newly diagnosed PCa who underwent [ 68 Ga]Ga‐PSMA‐11 PET/CT between 1/2/20 and 1/4/23, with one or more of three major risk factors (prostate‐specific antigen (PSA) ≥ 20, MRI T‐stage ≥ 3 or International Society of Urological Pathology (ISUP) grade ≥ 3) were included. Metrics collected included [ 68 Ga]Ga‐PSMA‐11 PET/CT primary index tumour maximum standardized uptake value (SUV max ), TNM stage, tumour histology, patient age, body mass index and treatment type.
Results
A total of 525 subjects were eligible for inclusion. A total of 22.1% had nodal or distant metastases on the baseline [ 68 Ga]Ga‐PSMA‐11 PET/CT (11.8% with one major risk factor, 25.6% with two and 43.5% with three). All three major risk factors (PSA ≥ 20, MRI T‐stage ≥ 3, ISUP grade ≥ 3) and the presence of a higher percentage of positive biopsy cores were significant independent risk factors for the presence of metastatic disease on multivariable analysis. Primary index tumour SUV max was associated with clinical risk factors, including ISUP grade in the surgical cohort. A total of 146 (27.8%) subjects underwent a radical prostatectomy, and 379 (72.2%) received non‐surgical management (including 242 (46.1%) who received curative intent radiotherapy (RT)).
Conclusion
This study provides real‐world validation of the clinical risk factors used for the ProPSMA study for [ 68 Ga]Ga‐PSMA‐11 PET/CT scan eligibility, which represent significant independent risk factors for the presence of nodal or distant metastases on baseline [ 68 Ga]Ga‐PSMA‐11 PET/CT.