Reader Training for the Restaging of Biochemically Recurrent Prostate Cancer Using 18F-Fluciclovine PET/CT.

18F-Fluciclovine is a novel PET/CT tracer. This blinded image evaluation (BIE) sought to demonstrate that, after limited training, readers naïve to 18F-fluciclovine could interpret 18F-fluciclovine images from subjects with biochemically recurrent prostate cancer with acceptable diagnostic performance and reproducibility. The primary objectives were to establish individual readers' diagnostic performance and the overall interpretation (2/3 reader concordance) compared with standard-of-truth data (histopathology or clinical follow-up) and to evaluate interreader reproducibility. Secondary objectives included comparison to the expert reader and assessment of intrareader reproducibility. Methods:18F-Fluciclovine PET/CT images (n = 121) and corresponding standard-of-truth data were collected from 110 subjects at Emory University using a single-time-point static acquisition starting 5 min after injection of approximately 370 MBq of 18F-fluciclovine. Three readers were trained using standardized interpretation methodology and subsequently evaluated the images in a blinded manner. Analyses were conducted at the lesion, region (prostate, including bed and seminal vesicle, or extraprostatic, including all lymph nodes, bone, or soft-tissue metastasis), and subject level. Results: Lesion-level overall positive predictive value was 70.5%. The readers' positive predictive value and negative predictive value were broadly consistent with each other and with the onsite read. Sensitivity was highest for readers 1 and 2 (68.5% and 63.9%, respectively) whereas specificity was highest for reader 3 (83.6%). Overall, prostate-level sensitivity was high (91.4%), but specificity was moderate (48.7%). Interreader agreement was 94.7%, 74.4%, and 70.3% for the lesion, prostate, and extraprostatic levels, respectively, with associated Fleiss' κ-values of 0.54, 0.50, and 0.57. Intrareader agreement was 97.8%, 96.9%, and 99.1% at the lesion level; 100%, 100%, and 91.7% in the prostate region; and 83.3%, 75.0%, and 83.3% in the extraprostatic region for readers 1, 2, and 3, respectively. Concordance between the BIE and the onsite reader exceeded 75% for each reader at the lesion, region, and subject levels. Conclusion: Specific training in the use of standardized interpretation methodology for assessment of 18F-fluciclovine PET/CT images enables naïve readers to achieve acceptable diagnostic performance and reproducibility when staging recurrent prostate cancer.

Journal of nuclear medicine : official publication, Society of Nuclear Medicine. 2017 Apr 06 [Epub]

Matthew P Miller, Lale Kostakoglu, Daniel Pryma, Jian Qin Yu, Albert Chau, Eric Perlman, Bonnie Clarke, Donald Rosen, Penelope Ward

Blue Earth Diagnostics (BED), Oxford, United Kingdom ., Department of Radiology, Icahn School of Medicine at Mount Sinai, New York, New York., Department of Radiology, University of Pennsylvania Perelman School of Medicine, Philadelphia, Pennsylvania., Fox Chase Cancer Center, Philadelphia, Pennsylvania., Blue Earth Diagnostics (BED), Oxford, United Kingdom., American College of Radiology, Philadelphia, Pennsylvania; and., Society of Nuclear Medicine and Molecular Imaging Clinical Trials Network, Reston, Virginia.