(UroToday.com) The 2023 European Society of Medical Oncology (ESMO) Annual Congress held in Madrid, Spain between October 20th and 24th, 2023 was host to a prostate cancer abstracts poster session. Dr. Giulio Francolini presented the early results of the PSICHE (PSMA guided approach for bIoCHEmical relapse after prostatectomy) trial.
Over the past several years, we have witnessed an increased uptake of PSMA-PET/CT for the staging of patients in the biochemically recurrent setting, given the improved performance characteristics of this imaging modality compared to conventional imaging.1 The use of PSMA-PET/CT in this setting has been associated with changes in the management plans, with 64% of patients in the CONDOR trial having a change in the intended disease management plan.2 However, to date, it remains unknown whether such changes in the management plan are associated with improved oncologic outcomes.
Several treatment paradigms have been suggested based on PSMA-PET/CT findings (e.g., metastasis-directed therapy for oligometastatic disease, salvage prostate radiotherapy for patients with negative or prostate localized disease, etc.). Nonetheless, the best management strategy for oligometastatic patients identified via PSMA-PET/CT imaging requires additional investigation. PSICHE (NCT05022914) is a prospective multicenter trial that aims to evaluate a 68Ga-PSMA-11 PET/CT imaging tailored strategy.
PSICHE includes patients with evidence of biochemical recurrence following radical prostatectomy, with a serum PSA level of 0.2 to 1.0 ng/ml who subsequently underwent 68Ga-PSMA-11 PET/CT. Following staging with PSMA-PET/CT, the management was performed per a pre-defined algorithm:
- Negative PSMA and prior post-operative adjuvant/salvage radiotherapy. Observation and re-staging at further PSA progression
- Negative staging or prostate-only disease. Prostate bed salvage radiotherapy
- Pelvic nodal recurrence (nodal disease <2 cm below the aortic bifurcation) or oligometastatic disease. SBRT to all disease sites
- Widespread metastatic disease. ADT +/- androgen receptor pathway inhibitor
In this analysis, Dr. Francolini and colleagues reported the early biochemical analysis focusing on complete biochemical response (PSA ≤0.2 ng/ml) and biochemical response (PSA ≤50% if compared to baseline value before treatment). Gastrointestinal and genitourinary toxicity were assessed according to CTCAE v 4.0.
Overall, 110 patients were included in the current analysis. At 3 months post-treatment, biochemical response outcomes were as follows:
- Complete biochemical response: 45.4%
- Any biochemical response: 53.6%
No grade 3+ adverse events were observed. Gastrointestinal toxicity was observed in 7/110 patients (all grade 1) and genitourinary events in 30/110 (only 3 grade 2, remaining all grade 1).
Based on these early results, Dr. Francolini and colleagues concluded that a PSMA-targeted treatment strategy is associated with early promising results and is well tolerated within the context of a prospective multicenter trial.
Presented by: Giulio Francolini, MD, Radiation Oncology Unit, Oncology Department, Azienda Ospedaliero Universitaria Careggi, Firenze, Italy
Written by: Rashid K. Sayyid, MD, MSc – Society of Urologic Oncology (SUO) Clinical Fellow at The University of Toronto, @rksayyid on Twitter during the 2023 European Society of Medical Oncology (ESMO) Annual Meeting, Madrid, Spain, Fri, Oct 20 – Tues, Oct 24, 2023.
References:
- Hofman MS, Lawrentschuk N, Francis, RJ, et al. Prostate-specific membrane antigen PET-CT in patients with high-risk prostate cancer before curative-intent surgery or radiotherapy (proPSMA): A prospective, randomized, multicentre study. Lancet 2020 Apr 11;395(10231):1208-1216.
- Morris MJ, Rowe SP, Gorin MA, et al. Diagnostic Performance of 18F-DCFPyL-PET/CT in Men with Biochemically Recurrent Prostate Cancer: Results from the CONDOR Phase III, Multicenter Study. Clin Cancer Res. 2021 Jul 1;27(13):3674-3682.