Investigators have found an increasing probability of upstaging on prostate-specific membrane antigen positron emission tomography (PSMA PET) among patients with clinically localized high-risk prostate cancer.
Using 2010-2017 data from the National Cancer Database, investigators identified 45,772 men with high-risk disease who underwent radical prostatectomy (median age 64 years). The median PSA level was 8.8 ng/mL and percentage of positive cores was 50%. Gleason grade group 4 and 5 disease affected 46.5% and 30.0% of the cohort, respectively.
Investigators calculated the likelihood of upstaging on Gallium [Ga68] PSMA PET using a University of California, Los Angeles, nomogram.
The median risk of PSMA PET upstaging overall was 16.3%, significantly increasing from 13.0% in 2010 to 17.6% in 2017, Jonathan E. Shoag, MD, of Cleveland Medical Center, Case Western Reserve University School of Medicine in Ohio, and colleagues reported in JAMA Network Open. From 2010 to 2017, the median risk of nodal upstaging significantly increased from 11.7% to 15.4% and distant metastatic upstaging from 3.6% to 4.7%.
Investigators found an increasing proportion of Gleason grade group 4 and 5 cancers after surgery. PSA, T stage, and the percentage of positive cores did not change.
With respect to accuracy, the nomogram had an area under the receiver operative curve of 0.74.
“While upstaging may be secondary to nodal or distant metastatic findings on PSMA PET, the risk of nodal upstaging in particular may affect the decision between surgery and radiation,” Dr Shoag’s team stated. “Therefore, with increasing risk of nodal upstaging, the immediate impact of stage migration from PSMA PET may be to alter treatment decisions in a substantial number of patients with high-risk prostate cancer.”
Disclosure: Some study authors declared affiliations with biotech, pharmaceutical, and/or device companies. Please see the original reference for a full list of authors’ disclosures.
Brant A, Lewicki P, Xiang M, et al. Risk of tumor upstaging with prostate-specific membrane antigen positron emission tomography in patients with high-risk prostate cancer. JAMA Netw Open. Published online September 12, 2022. doi:10.1001/jamanetworkopen.2022.31101