Combining PSA and PET features to select candidates for salvage lymph node dissection in recurrent prostate cancer.

To evaluate the relationship between pre-operative PSA value, 68Ga-prostate-specific-membrane-antigen (PSMA) PET performance and oncologic outcomes after salvage lymph node dissection (sLND) for biochemical recurrent prostate cancer (PCa).

The study included 164 patients diagnosed with ≤2 pelvic lymph-node recurrence(s) of PCa documented on 68Ga-PSMA PET scan and treated with pelvic ± retroperitoneal sLND at 11 high-volume centres between 2012 and 2019. Pathologic findings were correlated to PSA values at time of sLND, categorized in early (<0.5 ng/ml), low (0.5-0.99 ng/ml), moderate (1-1.5 ng/ml) and high (>1.5 ng/ml). Clinical recurrence (CR)-free survival after sLND was calculated using multivariable analyses and plotted over pre-operative PSA value.

Median [interquartile range (IQR)] PSA at sLND was 1.1 (0.6, 2.0) ng/ml, and 131 (80%) patients had one positive spot at PET scan. All patients received pelvic sLND, whereas 91 (55%) men received also retroperitoneal dissection. Median (IQR) number of node removed was 15 (6, 28). The rate of positive pathology increased as a function of pre-operative PSA value, with highest rates for patients with pre-operative PSA > 1.5 ng/ml (pelvic-only sLNDs: 84%; pelvic + retroperitoneal sLNDs: 90%). After sLND, PSA ≤ 0.3 ng/ml was detected in 67 (41%) men. On multivariable analyses, pre-operative PSA was associated with PSA response (p < 0.0001). There were 51 CRs after sLND. After adjusting for confounders, we found a significant, non-linear relationship between PSA level at sLND and the 12-month CR-free survival (p < 0.0001), with the highest probability of freedom from CR for patients who received sLND at PSA level ≥1 ng/ml.

In case of PET-detected nodal recurrences amenable to sLND, salvage surgery was associated with the highest short-term oncologic outcomes when performed in men with PSA ≥ 1 ng/ml. Awaiting confirmatory data from prospective trials, these findings may help physicians to optimize the timing for 68Ga-PSMA PET in biochemical recurrent PCa.

BJUI compass. 2022 Aug 04*** epublish ***

Carlo A Bravi, Axel Heidenreich, Nicola Fossati, Giorgio Gandaglia, Nazareno Suardi, Elio Mazzone, Armando Stabile, Vito Cucchiara, Daniar Osmonov, Klaus-Peter Juenemann, R Jeffrey Karnes, Alexander Kretschmer, Alexander Buchner, Christian Stief, Andreas Hiester, Peter Albers, Gaëtan Devos, Steven Joniau, Hendrik Van Poppel, Bernhard Grubmüller, Shahrokh Shariat, Derya Tilki, Markus Graefen, Inderbir S Gill, Alexander Mottrie, Pierre I Karakiewicz, Francesco Montorsi, Alberto Briganti, David Pfister

Division of Oncology/Unit of Urology, URI IRCCS Ospedale San Raffaele Milan Italy., Department of Urology University of Cologne Cologne Germany., Department of Urology, Policlinico San Martino Hospital University of Genova Genoa Italy., Department of Urology and Pediatric Urology, Campus Kiel University Hospital Schleswig Holstein Kiel Germany., Department of Urology Mayo Clinic Rochester Minnesota USA., Department of Urology Ludwig-Maximilians-University Munich Germany., Universitätsklinikum des Saarlandes Homburg Germany., Department of Urology, Medical Faculty Heinrich-Heine-University Düsseldorf Germany., Department of Urology University Hospitals Leuven Leuven Belgium., Department of Urology Medical University of Vienna Vienna Austria., Department of Urology University Hospital Hamburg-Eppendorf Hamburg Germany., USC Institute of Urology University of Southern California Los Angeles California USA., Department of Urology OLV Ziekenhuis Aalst Aalst Belgium., Cancer Prognostics and Health Outcomes Unit University of Montreal Health Centre Montreal Quebec Canada.