PSMA guided approach for bIoCHEmical relapse after prostatectomy- (PSICHE) trial (NCT05022914). Detection rate and treatment decision after 68Ga-PSMA PET/CT within a prospective study.

Ultrasensitive imaging has been demonstrated to influence biochemical relapse treatment. PSICHE is a multicentric prospective study, aimed at exploring detection rate with 68Ga-PSMA-11 positron emission tomography/computed tomography (PET/CT) and outcomes with a predefined treatment algorithm tailored to the imaging.

Patients affected by biochemical recurrence after surgery (prostate specific antigen [PSA] > 0.2 < 1 ng/mL) underwent staging with 68Ga-PSMA PET/CT. Management followed this treatment algorithm accordingly with PSMA results: prostate bed salvage radiotherapy (SRT) if negative or positive within prostate bed, stereotactic body radiotherapy (SBRT) if pelvic nodal recurrences or oligometastatic disease, androgen deprivation therapy (ADT) if nonoligometastatic disease. Chi-square test was used to evaluate the relationship between baseline features and rate of positive PSMA PET/CT.

One hundred patients were enrolled. PSMA results were negative/positive in the prostate bed in 72 patients, pelvic nodal or extrapelvic metastatic disease were detected in 23 and 5 patients. Twenty-one patients underwent observation because of prior postoperative radiotherapy (RT)/treatment refusal. Fifty patients were treated with prostate bed SRT, 23 patients underwent SBRT to pelvic nodal disease, five patients were treated with SBRT to oligometastatic disease. One patient underwent ADT. NCCN high-risk features, stage > pT3 and ISUP score >3 reported a significantly higher rate of positive PSMA PET/CT after restaging (p = 0.01, p = 0.02, and p = 0.002). By quartiles of PSA, rate of positive PSMA PET/CT was 26.9% (>0.2; <0.29 ng/mL), 24% (>0.3; <0.37 ng/mL), 26.9% (>0.38; <0.51 ng/mL), and 34.7% (>0. 52; <0.98 ng/mL).

PSICHE trial constitute a useful platform to collect data within a clinical framework where modern imaging and metastasis-directed therapy are integrated.

The Prostate. 2023 Jun 08 [Epub ahead of print]

Giulio Francolini, Marco Banini, Vanessa Di Cataldo, Beatrice Detti, Saverio Caini, Mauro Loi, Gabriele Simontacchi, Isacco Desideri, Daniela Greto, Marianna Valzano, Manuele Roghi, Sergio Serni, Luca Vaggelli, Viola Salvestrini, Luca Visani, Carlotta Becherini, Emanuela Olmetto, Ciro Franzese, Davide Baldaccini, Marta Scorsetti, Martina Sollini, Arturo Chiti, Icro Meattini, Richard K Valicenti, Lorenzo Livi

Radiation Oncology Unit, Azienda Ospedaliero-Universitaria Careggi, Florence, Italy., Department of Biomedical, Experimental and Clinical Sciences "Mario Serio", University of Florence, Florence, Italy., Cancer Risk Factors and Lifestyle Epidemiology Unit, Institute for Cancer Research, Prevention and Clinical Network (ISPRO), Florence, Italy., Unit of Urological Robotic Surgery and Renal Transplantation and Department of Experimental and Clinical Medicine, University of Florence, Careggi Hospital, Florence, Italy., Nuclear Medicine Division, Careggi University Hospital, Florence, Italy., Radiotherapy and Radiosurgery Department, Humanitas Clinical and Research Center, IRCSS, Milan-Rozzano, Italy., Department of Biomedical Sciences and Department of Biomedical Sciences, Humanitas University, Milan, Italy., Nuclear Medicine Department, IRCCS San Raffaele, Milan, Italy., Department of Radiation Oncology, UC Davis, Davis, California, USA.