(UroToday.com) The 2022 EAU annual meeting featured a session on improvements in metastatic prostate cancer focusing on imaging and treatment, including a presentation by Dr. Sophie Knipper discussing oncological outcomes of patients treated with salvage lymph node dissection via PSMA radioguided surgery. PSMA PET allows detection of small and/or atypically localized metastatic prostate cancer lesions. In a subset of patients with recurrent oligometastatic prostate cancer, salvage surgery with PSMA-targeted radioguidance may be of value. This study aimed to evaluate the oncological outcomes of salvage PSMA-targeted radioguidance for oligo-recurrent prostate cancer and determine predictive preoperative factors of improved outcomes.
In this cohort study within two tertiary care centers, patients with biochemical recurrence after radical prostatectomy and imaging with PSMA PET receiving salvage PSMA-targeted radioguidance between 2014 and 2020 were analyzed. Kaplan-Meier and multivariable Cox regression models adjusted for various parameters were used to test for biochemical recurrence-free survival and therapy-free survival differences. Postoperative complications were classified according to Clavien-Dindo.
Overall, there were 364 patients assessed. At PSMA-targeted radioguidance, median age and preoperative PSA was 67 (IQR 61-71) years and 1.0 (IQR 0.5-1.9) ng/ml, respectively. The full baseline characteristics of the patients is as follows:
On preoperative imaging, 241 (66%) patients had one lesion and 246 (68%) patients had only pelvic lesions. Metastatic soft-tissue lesions were removed in 343 (94%) patients with a complete biochemical response (PSA < 0.2 ng/mL) in 60% of patients:
Within three months from surgery, 24 (6.6%) patients suffered from Clavien-Dindo complications grade III-IV:
During follow-up, 235 patients experienced biochemical recurrence and 129 patients received further therapy. The median follow-up for patients who did not experience biochemical recurrence and who did not receive further therapy was 11.1 months and 10.5 months, respectively. The median biochemical recurrence-free survival and therapy-free survival was 7.8 (IQR 5.4-10.9) and 34.9 (IQR 24.7-43.5) months:
At two years of follow-up, biochemical recurrence-free survival rate was 31.9% and therapy-free survival rate was 56.6%. In multivariable analyses, higher preoperative PSA (HR 1.07, p = 0.009), higher number of PSMA-avid lesions on preoperative imaging (HR 1.23, p = 0.002) and multiple (pelvic plus retroperitoneal) localizations (HR 1.90, p = 0.004), as well as retroperitoneal localization (HR 2.04, p = 0.002) of lesions in PSMA PET imaging were independent predictors of biochemical recurrence after PSMA-targeted radioguidance. Dr. Knipper noted several limitations, including the retrospective study design, lack of a control group, and only intermediate-term follow-up without standardized trigger for next treatment.
Dr. Knipper concluded her presentation discussing oncological outcomes of patients treated with salvage lymph node dissection via PSMA radioguided surgery with the following take-home messages:
- Salvage surgery in oligo-recurrent prostate cancer is still currently an experimental treatment approach
- Careful patient selection is mandatory based on life expectancy, low PSA values, and low number of PSMA PET avid lesions located in the pelvis
- Further studies are needed to confirm these findings and define the oncological value of salvage surgical procedures in oligo-recurrent prostate cancer
Presented by: Sophie Knipper, MD, University Hospital Hamburg-Eppendorf, Martini-Klinik Prostate Cancer Center, Hamburg, Germany
Co-Authors: Mehdi Irai M.1, Simon R.2, Köhler D.3, Isabel R.4, Eiber M.4, Van Leeuwen F.W.B.1, Van Leeuwen P.5, Budäus L.1, Steuber T.1, Graefen M.1, Tennstedt P.1, Heck M.2, Horn T.2, Maurer T.1
Affiliations: 1University Hospital Hamburg-Eppendorf, Martini-Klinik Prostate Cancer Center, Hamburg, Germany, 2Technical University of Munich, Dept. of Urology, Munich, Germany, 3University Hospital Hamburg-Eppendorf, Dept. of Radiology and Nuclear Medicine, Hamburg, Germany, 4Technical University of Munich, Dept. of Nuclear Medicine, Munich, Germany, 5Antoni van Leeuwenhoek Hospital – the Netherlands Cancer Institute, Dept. of Urology, Amsterdam, The Netherlands
Written by: Zachary Klaassen, MD, MSc – Urologic Oncologist, Assistant Professor of Urology, Georgia Cancer Center, Augusta University/Medical College of Georgia, @zklaassen_md on Twitter during the 2022 European Association of Urology (EAU) Annual Hybrid Meeting, Amsterdam, NL, Fri, July 1 – Mon, July 4, 2022.