(UroToday.com) The 2022 ASCO annual meeting featured a session on kidney and bladder cancer, including a presentation by Dr. Shivanshan Pathmanathan discussing PSMA PET-CT for advanced RCC. The proPSMA study demonstrated that PSMA PET-CT provides accurate staging for prostate cancer,1 however the PSMA protein is also expressed in non-prostate malignancies, including in the neovasculature of solid organ tumors such as RCC. There is an emerging role of the use of PSMA PET in RCC. At the 2022 ASCO meeting, Dr. Pathmanathan and colleagues reported their experience using of PSMA PET-CT in recurrent or metastatic RCC.
This was a multicenter, retrospective study involving 3 centers in Queensland, Australia (Royal Brisbane and Women’s Hospital, Princess Alexandra Hospital, and Wesley Hospital). Patients were included if they underwent PSMA PET (68Ga-PSMA-11 or 18F-PSMA-1007) and conventional diagnostic CT for metastatic or recurrent RCC between January 2015 and June 2020. Retrospective chart reviews were conducted using a standardized collection template. The outcomes included the percentage of patients who had a change in management secondary to PSMA PET findings, comparison of metastasis detection for PSMA PET versus CT, and biopsy histology of PSMA avid sites.
There were 42 PSMA PET-CTs performed in 40 RCC patients, including 10 patients (25%) and 30 patients (75%) that had a PSMA PET for metastatic disease and recurrent disease settings, respectively:
Overall, 12 patients (30%, n=3 metastatic, n=9 recurrent) had a change in management following PSMA PET. In the metastatic disease group, 2 patients (20%) underwent initial systemic therapy (after histological confirmation) due to higher burden of disease shown with PSMA PET than CT, while systemic therapy was changed for 1 patient (10%). The following figure highlights a case of liver metastasis being identified on PSMA PET occult on CT imaging:
In the recurrent disease group, PSMA improved delineation of suspected recurrence (compared to CT) resulting in resection rather than surveillance (n=4; 13%) or change in surgical approach for resection (n=1; 3%). PSMA PET distribution showed more metastatic sites than CT leading to systemic therapy rather than resection of recurrence (n=2; 7%), while absent PSMA activity for suspected recurrence on CT led to surveillance rather than resection (n=2; 7%). PSMA PET detected more sites of metastases compared with conventional scan in 6 patients (60%) with metastatic disease and in 9 patients (30%) with recurrent disease. The following figure highlights PSMA PET abdominal wall recurrence not identified on CT imaging:
There were 25 patients that had biopsy of PSMA avid sites, with the majority of patients having confirmed recurrence of clear cell renal carcinoma (n= 22; 88%). Other histology included sarcomatoid renal cell carcinoma, carcinoid, and urothelial cancer (all n=1; 4%):
Dr. Pathmanathan concluded this presentation discussing PSMA PET-CT for advanced RCC with the following take-home messages:
- PSMA PET detected more accurately metastatic and recurrent disease, with high pathological concordance, to result in change in management for 30% of patients
- There was high pathological concordance with clear cell renal cell carcinoma and PSMA avid sites
- Prospective study is warranted to further investigate the utility of PSMA PET scan in advanced RCC
Presented by: Shivanshan Pathmanathan, MD, Department of Oncology, Royal Brisbane and Women’s Hospital, Brisbane, QLD, Australia
Co-Authors: Arsalan Tariq, Chun Loo Gan, Adam Pearce, Handoo Rhee, Samuel Kyle, Sheliyan Raveenthiran, David Wong, Rhiannon McBean, Philip Marsh, Steven Goodman, Nattakorn Dhiantravan, Rachel Esler, Nigel Dunglison, Anojan Navaratnam, John Yaxley, Paul Thomas, David A. Pattison, Jeffrey C. Goh, Matthew Roberts
Affiliations: Department of Urology, Royal Brisbane and Women's Hospital, Brisbane, Australia, Department of Urology, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia, Department of Urology, Princess Alexandra Hospital, Brisbane, QLD, Australia, Department of Nuclear Medicine, Royal Brisbane and Women’s Hospital, Brisbane, QLD, Australia, Department of Urology, Redcliffe Hospital, Brisbane, QLD, Australia, Department of Radiology & Nuclear Medicine, The Wesley Hospital, Brisbane, QLD, Australia, Department of Diagnostic Radiology, Princess Alexandra Hospital, Brisbane, QLD, Australia, Department of Nuclear Medicine, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia, Royal Brisbane and Women's Hospital, Brisbane, QLD, Australia, Wesley Urology Clinic, The Wesley Hospital, Brisbane, QLD, Australia, Department of Urology, Royal Brisbane and Women’s Hospital, Brisbane, QLD, Australia
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 American Society of Clinical Oncology (ASCO) Annual Meeting, Chicago, IL, Fri, June 3 – Mon, June 7, 2022.
References: