Prediction of clinically significant prostate cancer by [68 Ga]Ga-PSMA-11 PET/CT: a potential tool for selecting patients for active surveillance

• Published in: European journal of nuclear medicine and molecular imaging Vol. 51; no. 5; pp. 1467 - 1475
• Main Authors: Akcay, Kaan, Kibar, Ali, Sahin, Onur Erdem, Demirbilek, Muhammet, Beydagi, Gamze, Asa, Sertac, Aghazada, Fuad, Toklu, Turkay, Selcuk, Nalan Alan, Onal, Bulent, Kabasakal, Levent
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-04-2024; Springer Nature B.V
• Subjects: Biopsy; Cardiology; Clinical significance; Computed tomography; Correlation; Imaging; Medical imaging; Medicine; Medicine & Public Health; Nuclear Medicine; Oncology; Original Article; Orthopedics; Pathology; Patients; Positron emission; Prostate cancer; Prostatectomy; Radiology; Sensitivity; Statistical analysis; Surveillance; Clinically significant prostate cancer; PSMA; Active surveillance; Prostate biopsy; Prostate-specific membrane antigen; PSMA-PET/CT
• ISSN: 1619-7070; 1619-7089
• DOI: 10.1007/s00259-023-06556-y

Purpose
In our study, our aim was to investigate the role of [
68
 Ga]Ga-PSMA-11 PET /CT imaging in the diagnosis of clinically significant prostate cancer (csPCa) (ISUP GG 2 and higher) in patients initially diagnosed with ISUP GG 1 and 2 after prostate biopsy.
Materials and methods
We retrospectively reviewed 147 patient records in whom [
68
 Ga]Ga-PSMA-11 PET/CT imaging was performed preoperatively. All patients were initially diagnosed with ISUP GG 1 and 2 PCa by biopsy. Final pathology reports were obtained after radical prostatectomy. The [
68
 Ga]Ga-PSMA-11 PET/CT images were evaluated to determine the PRIMARY score. Patients’ mpMRI-PIRADS scores were also recorded when available and analyzed in correlation with the pathology results.
Results
For the 114 patients scored using PRIMARY, 19 out of 37 patients with scores of 1 and 2 (51%) were diagnosed with csPCa. Of the 77 patients with PRIMARY scores between 3 and 5, 64 (83%) had csPCa. Notably, every patient with a PRIMARY score of 5 had csPCa. PRIMARY scoring had a sensitivity of 77% and specificity of 58%, with a positive predictive value of 83%. A moderate correlation was observed between PRIMARY scores and ISUP GG (Rho = 0.54,
p
 < 0.001). In contrast, the PIRADS score displayed a sensitivity and specificity of 86% and 25% respectively, with a positive predictive value of 68%. No substantial correlation was found between PIRADS and ISUP GG. Statistical analysis revealed a significant correlation between PRIMARY and ISUP GG (
p
 < 0.001), but not between PIRADS and ISUP GG (
p
 = 0.281). Comparatively, PRIMARY scoring was significantly more reliable than PIRADS scoring in identifying csPCa.
Conclusion
[
68 
Ga]Ga-PSMA-11 PET/CT imaging is promising for distinguishing high-risk prostate cancer patients from those apt for active surveillance, potentially aiding in the identification of csPCa.