68Ga PSMA PET/CT predicts complete biochemical response from radical prostatectomy and lymph node dissection in intermediate and high-risk prostate cancer

To determine the value of 68Ga-PSMA-11 PET/CT in men with newly diagnosed prostate cancer (PC).

We analysed results of 140 men with intermediate and high-risk PC. All men underwent 68Ga-PSMA-11 PET/CT and mpMRI prior to radical prostatectomy (RP) with extended pelvic lymph node dissection (ePLND). For each patient, the clinical and pathological features were recorded. Prostate-specific antigen (PSA) was documented at staging scan, and following surgery (median 110 days (IQR 49-132). A PSA of ≥0.03ng/ml was classified as biochemical persistence (BCP). Logistic regression was performed for association of clinical variables and BCP.

In these 140 intermediate and high-risk PC patients, 27.1% had PSMA PET/CT positive findings in the pelvic lymph nodes (LN). Sensitivity and specificity for detection of LN metastases were 53 and 88% (PSMA PET/CT) and 14 and 99% (mpMRI) respectively. The overall BCP rate was 25.7%. The BCP rate was 16.7% in men who were PSMA PET/CT LN negative compared to 50% in men who were PSMA PET/CT LN positive (p<0.05). The presence of PSMA positive pelvic LN was more predictive for BCP to RP than cT-stage, PSA and the Gleason score, adjusted for surgical margins status.

68Ga-PSMA-11 PET/CT is highly predictive for BCP to RP, and should play an important role informing men with intermediate or high-risk PC. This article is protected by copyright. All rights reserved.

BJU international. 2018 Aug 03 [Epub ahead of print]

Pim J van Leeuwen, Maarten Donswijk, Rohan Nandurkar, Philip Stricker, Bao Ho, Stijn Heijmink, Esther M K Wit, Corinne Tillier, Erik van Muilenkom, Quoc Nguyen, Henk G van der Poel, Louise Emmett

Department of Urology, The Netherlands Cancer Institute, the Netherlands., Department of Nuclear Medicine, The Netherlands Cancer Institute, the Netherlands., Faculty of Medicine, University of New South Wales Sydney, Sydney, Australia., The Australian Prostate Cancer Research Centre-NSW The Garvan Institute of Medical Research, Sydney, Australia., Department of Theranostics and Nuclear Medicine, St Vincent's Hospital Sydney, Sydney, Australia., Department of Radiology, The Netherlands Cancer Institute, the Netherlands.