(UroToday.com) The 2023 EAU annual meeting included a session on the role of imaging and PSA density for biopsy indication, and tumor staging, featuring a presentation by Dr. Abdullah Al-Mitwalli discussing the cost effectiveness of PSMA PET for high risk prostate cancer. PSMA PET using Gallium-68 is now a documented imaging modality for high-risk primary prostate cancer to assess nodal and metastatic disease.1 Additionally, PSMA PET is often performed alongside conventional imaging including mpMRI and bone scan. However, it’s role in the diagnostic pathway is not clearly defined.
This study was a retrospective assessment of imaging for high-risk prostate cancer treatment in a single high-volume center over a 2-year period. High risk features were defined as: cT3, Gleason ≥ 8, PSA > 20 ng/mL. All patients had a pre-biopsy multi-parametric MRI, prostate cancer diagnosed on biopsy, followed by a bone scan. If the bone scan was negative, they proceeded to have a PSMA PET.
Overall, there was a total of 120 patients included in the study with a mean age of 69.1 years (+/- 7.2) and a mean PSA of 24.9 ng/mL (range: 1.5 – 238.0). The baseline characteristics are summarized as follows:
Conventional imaging detected nodal involvement in 19 (15%) of the patients, while PSMA detected nodal disease in 45 (37.5%) of patients (p <0.001):
PSMA detection of metastatic disease was identified in 34 (28.3%) patients, while conventional imaging identified metastasis in only 6 (8.3%) of cases (p < 0.001):
The concurrence between conventional imaging and PSMA was poor for detecting nodal (k =0.215, p <0.002) and metastatic ((k= 0.232, p<0.001) spread. The mean time from the initial mpMRI to PSMA PET was 93 days, while the mean time from bone scan to the PSMA PET was 58 days. The cost per bone scan was £500, while a PSMA PET scan cost was £2,800.
Dr. Al-Mitwalli concluded this presentation discussing the cost effectiveness of PSMA PET for high risk prostate cancer with the following take-home messages:
- High risk prostate cancer patients should have a bone scan to identify metastases. If this is negative, PSMA PET should be performed for staging
- This provides selective, pragmatic use for PSMA PET to provide a cost-effective and a stepwise approach for diagnostic options in high-risk prostate cancer
- A limitation of this study is the lack of outcome data for subsequent treatment changes
Presented by: Abdullah Al-Mitwalli, Swansea University Health Board, Dept. of Urology, Swansea, United Kingdom
Co-Authors:
Mubarak M.M1, Rashid M.R1, Jefferies M.J1,Kandaswamy G.K1,Powles A.P2
Affiliations: 1Swansea University Health Board, Dept. of Urology, Swansea, United Kingdom, 2Swansea University Health Board, Dept. of Radiology, Swansea, United Kingdom
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 2023 European Association of Urology (EAU) Annual Meeting, Milan, IT, Fri, Mar 10 – Mon, Mar 13, 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.