Interreader and intrareader reproducibility of 18F-flotufolastat PET/CT scans in newly diagnosed and recurrent prostate cancer patients was assessed from masked image evaluations from two phase 3 studies. Methods: 18F-flotufolastat PET/CT images of newly diagnosed (n = 352) or recurrent (n = 389) patients were evaluated by 3 masked readers. Cohen κ was used to assess pairwise patient- and region-level interreader agreement. Agreement among all readers was assessed using Fleiss κ. Intrareader agreement between the first and repeat read (20% of images, ≥4 wk later) was assessed using Cohen κ. Results: Pairwise interreader agreement was 95% or better (newly diagnosed) and 75% or better (recurrent). The κ coefficients were impacted by the high-agreement-low-κ paradox: Cohen κ ranged from not estimable to 0.55, whereas Fleiss κ was 0.50 (newly diagnosed) and 0.41 (recurrent). Agreement was highest in the prostate of newly diagnosed patients (≥95%) and in the pelvic lymph nodes in recurrent patients (≥87%). Intrareader agreement was 86% or better across both populations. Conclusion: 18F-flotufolastat PET/CT images can be reliably interpreted, with a high degree of inter- and intrareader agreement.
Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2024 Jun 13 [Epub ahead of print]
Phillip H Kuo, Giuseppe Esposito, Gary A Ulaner, Don Yoo, Katherine Zukotynski, Gregory C Ravizzini, Ross Penny, Matthew P Miller, Albert Chau, Phillip Davis, Brian F Chapin, David M Schuster, SPOTLIGHT and LIGHTHOUSE study groups
Departments of Medical Imaging, Medicine, and Biomedical Engineering, University of Arizona, Tucson, Arizona; ., Department of Nuclear Medicine, Medstar Georgetown University Hospital, Washington, District of Columbia., Department of Molecular Imaging and Therapy, Hoag Family Cancer Institute, Irvine, California., Warren Alpert Medical School of Brown University, Providence, Rhode Island., Department of Radiology, McMaster University, Hamilton, Ontario, Canada., Division of Diagnostic Imaging, Department of Nuclear Medicine, University of Texas MD Anderson Cancer Center, Houston, Texas., Blue Earth Diagnostics Ltd., Oxford, United Kingdom., Blue Earth Diagnostics Inc., Monroe Township, New Jersey., Department of Urology, University of Texas MD Anderson Cancer Center, Houston, Texas; and., Division of Nuclear Medicine and Molecular Imaging, Department of Radiology and Imaging Sciences, Emory University, Atlanta, Georgia.