Prostate-specific membrane antigen (PSMA) is overexpressed in the neovasculature of renal cell carcinoma (RCC). However, there remains limited evidence regarding the use of PSMA positron emission tomography/computed tomography (PET/CT) in RCC.
To assess the impact of PSMA PET/CT in the management of metastatic RCC.
This was a retrospective review of patients who underwent PSMA PET/CT from 2014 to 2020 for restaging or suspected metastatic RCC in a tertiary academic setting.
Management plans before and after PSMA PET/CT were recorded. Impact was classified as high (change of treatment intent, modality, or site), medium (change in treatment method), or low. Secondary outcomes included the patient-level detection rate, PSMA PET/CT parameters, sensitivity, and comparison to CT and, if available, fluorodeoxyglucose (FDG) PET/CT.
Sixty-one patients met the inclusion criteria, of whom 54 (89%) had clear cell RCC. PSMA-positive disease was detected in 51 patients (84%). For 30 patients (49%) there was a change in management due to PSMA PET/CT (high impact, 29 patients, 48%). In 15 patients (25%), more metastases were detected on PSMA PET/CT than on CT. The sensitivity of combined PSMA PET/CT and diagnostic CT was 91% (95% confidence interval 77-98%). In a subcohort of 40 patients, the detection rate was 88% for PSMA and 75% for FDG PET/CT (p = 0.17). The maximum standardised uptake value (SUVmax) was higher for PSMA than for FDG PET/CT (15.2 vs 8.0; p = 0.02). Limitations include selection bias due to the retrospective design, and a lack of corresponding histopathology for all patients.
PSMA PET/CT is a promising imaging modality in metastatic RCC and led to a change in management in 49% of patients. PSMA PET/CT detected additional metastases compared to CT in 25% of patients and registered a significantly higher SUVmax than FDG PET/CT. Prospective studies are required to further define its role.
We report on a group of patients undergoing a new type of imaging for suspected advanced kidney cancer, called PSMA PET/CT. This imaging changed the management plan in 49% of the patients. PSMA PET/CT detected metastases in 84% of our patients and detected more metastases than computed tomography imaging in 25%.
European urology open science. 2022 Aug 29*** epublish ***
Cristian Udovicich, Jason Callahan, Mathias Bressel, Wee Loon Ong, Marlon Perera, Ben Tran, Arun Azad, Shankar Haran, Daniel Moon, Sarat Chander, Mark Shaw, Renu Eapen, Jeremy Goad, Nathan Lawrentschuk, Declan G Murphy, Michael Hofman, Shankar Siva
Department of Radiation Oncology, Peter MacCallum Cancer Centre, Melbourne, Australia., Department of Molecular Imaging and Therapeutic Nuclear Medicine, Peter MacCallum Cancer Centre, Melbourne, Australia., Centre for Biostatistics and Clinical Trials, Peter MacCallum Cancer Centre, Melbourne, Australia., Austin Health, Department of Surgery, The University of Melbourne, Melbourne, Australia., Sir Peter MacCallum Department of Oncology, The University of Melbourne, Melbourne, Australia., Royal Melbourne Hospital Clinical School, The University of Melbourne, Melbourne, Australia., Division of Cancer Surgery, Peter MacCallum Cancer Centre, Melbourne, Australia.