Histopathology-validated lesion detection rates of clinically significant prostate cancer with mpMRI, [ 68 Ga]PSMA-11-PET and [ 11 C]Acetate-PET.

Abstract

OBJECTIVE:

PET/CT and multiparametric MRI (mpMRI) are important diagnostic tools in clinically significant prostate cancer (csPC). The aim of this study was to compare csPC detection rates with [ 68 Ga]PSMA-11-PET (PSMA)-PET, [ 11 C]Acetate (ACE)-PET, and mpMRI with histopathology as reference, to identify the most suitable imaging modalities for subsequent hybrid imaging. An additional aim was to compare inter-reader variability to assess reproducibility.

METHODS:

During 2016-2019, all study participants were examined with PSMA-PET/mpMRI and ACE-PET/CT prior to radical prostatectomy. PSMA-PET, ACE-PET and mpMRI were evaluated separately by two observers, and were compared with histopathology-defined csPC. Statistical analyses included two-sided McNemar test and index of specific agreement.

RESULTS:

Fifty-five study participants were included, with 130 histopathological intraprostatic lesions >0.05 cc. Of these, 32% (42/130) were classified as csPC with ISUP grade ≥2 and volume >0.5 cc. PSMA-PET and mpMRI showed no difference in performance ( P  = 0.48), with mean csPC detection rate of 70% (29.5/42) and 74% (31/42), respectively, while with ACE-PET the mean csPC detection rate was 37% (15.5/42). Interobserver agreement was higher with PSMA-PET compared to mpMRI [79% (26/33) vs 67% (24/38)]. Including all detected lesions from each pair of observers, the detection rate increased to 90% (38/42) with mpMRI, and 79% (33/42) with PSMA-PET.

CONCLUSION:

PSMA-PET and mpMRI showed high csPC detection rates and superior performance compared to ACE-PET. The interobserver agreement indicates higher reproducibility with PSMA-PET. The combined result of all observers in both PSMA-PET and mpMRI showed the highest detection rate, suggesting an added value of a hybrid imaging approach.

• Authors: Kristina Sandgren, Sara N Strandberg, Joakim H Jonsson, Josefine Grefve, Angsana Keeratijarut Lindberg, Erik Nilsson, Anders Bergh, Karin Söderkvist, Camilla Thellenberg Karlsson, Bengt Friedrich, Anders Widmark, Lennart Blomqvist, Vibeke Berg Loegager, Jan Axelsson, Mattias Ögren, Margareta Ögren, Tufve Nyholm, Katrine Riklund
• Journal: Nuclear medicine communications (Nucl Med Commun) Vol. 44 Issue 11 Pg. 997-1004 (Nov 01 2023) ISSN: 1473-5628 [Electronic] England
• PMID: 37615497 (Publication Type: Journal Article)
• Copyright: Copyright © 2023 The Author(s). Published by Wolters Kluwer Health, Inc.