Prostate-specific membrane antigen (PSMA) positron emission tomography (PET) imaging parameters are moderately associated with clinical risk factors in patients with nonmetastatic prostate cancer, but none outperform the maximum standardized uptake value (SUVmax), according to a study published online April 22 in Frontiers in Oncology.
Sebastian Zschaeck, from Humboldt-Universität zu Berlin, and colleagues conducted a retrospective analysis of 135 consecutive patients with nonmetastatic prostate cancer and PSMA-PET before receiving any treatment. They examined the association between clinical risk parameters and quantitative PET parameters, including SUVmax, mean SUV (SUVmean), tumor asphericity (ASP), and PSMA tumor volume (PSMA-TV).
The researchers found that most of the imaging parameters examined were highly correlated (correlation coefficients between 0.20 and 0.95). There was a low-to-moderate, but significant, correlation for all imaging parameters with prostate-specific antigen values (0.19 to 0.45), and Gleason scores (0.17 to 0.31), apart from ASP, which was not significantly correlated with Gleason score. For all investigated quantitative PSMA-PET parameters, the receiver operating characteristics for detection of D’Amico high-risk patients showed poor-to-fair sensitivity and specificity (areas under the curve between 0.63 and 0.73). For detection of high-risk patients, comparison of areas under the curve between quantitative PET parameters by DeLong test showed significant superiority of SUVmax versus SUVmean. Of the investigated imaging parameters, none significantly outperformed SUVmax.
“Further analysis of additional quantitative PET parameters like ASP or PSMA-TV did not show superiority compared to SUVmax in this monocenter investigation,” the authors concluded.