68Ga-PSMA PET/CT based primary staging and histological correlation after extended pelvic lymph node dissection at radical prostatectomy.

Prostate-specific membrane antigen positron emission tomography-computed tomography (PSMA PET/CT) represents the upcoming standard for the staging of prostate cancer (PCa). However, there is still an unmet need for the validation of PSMA PET/CT at primary staging and consecutive histological correlation. Consequently, we decided to analyze the prediction parameter of PSMA PET/CT at primary staging.

We relied on 90 ≥ intermediate-risk PCa patients treated with radical prostatectomy (RP) and extended pelvic lymph node dissection. All patients were administered to 68Ga-PSMA PET/CT prior to surgery. 68Ga-PSMA PET/CT data were retrospectively reevaluated by a single radiologist and consequently compared to histological results from RP. Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) for the detection of lymph node metastases were analyzed per-patient (n = 90), per-pelvic side (n = 180), and per-anatomic-region (external iliac artery and vein left/right vs. obturator fossa left/right vs. internal iliac artery left/right) (n = 458), respectively.

Sensitivity, specificity, PPV, and NPV per-patient were: 43.8, 96.0, 70.0, and 88.8%, respectively. Sensitivity, specificity, PPV, and NPV per-pelvic-side were: 42.9, 95.6, 56.3, and 92.7%, respectively. Sensitivity, specificity, PPV, and NPV per-anatomic-region were: 47.6, 98.9, 66.7, and 97.5%, respectively.

Negative 68Ga-PSMA PET/CT results were highly reliable in our study. Positive 68Ga-PSMA PET/CT results, however, revealed less reliable results. Larger and ideally prospective trials are justified to clarify the potential role of PSMA PET/CT based primary staging.

World journal of urology. 2020 Feb 26 [Epub ahead of print]

J Kopp, D Kopp, E Bernhardt, L Manka, A Beck, H Gerullis, P Karakiewicz, W Schoerner, P Hammerer, Jonas Schiffmann

Department of Urology, Academic Hospital Braunschweig, Braunschweig, Germany., Department of Radiology, Academic Hospital Braunschweig, Braunschweig, Germany., University Hospital for Urology, Klinikum Oldenburg, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany., Cancer Prognostics and Health Outcomes Unit, University of Montreal Health Center, Montreal, Canada., University Hospital for Urology, Klinikum Oldenburg, School of Medicine and Health Sciences, Carl von Ossietzky University Oldenburg, Oldenburg, Germany. .