RT Journal Article
SR Electronic
T1 Does PET SUV Harmonization Affect PERCIST Response Classification?
JF Journal of Nuclear Medicine
JO J Nucl Med
FD Society of Nuclear Medicine
SP 1699
OP 1706
DO 10.2967/jnumed.115.171983
VO 57
IS 11
A1 Elske Quak
A1 Pierre-Yves Le Roux
A1 Charline Lasnon
A1 Philippe Robin
A1 Michael S. Hofman
A1 David Bourhis
A1 Jason Callahan
A1 David S. Binns
A1 Cédric Desmonts
A1 Pierre-Yves Salaun
A1 Rodney J. Hicks
A1 Nicolas Aide
YR 2016
UL http://jnm.snmjournals.org/content/57/11/1699.abstract
AB Pre- and posttreatment PET comparative scans should ideally be obtained with identical acquisition and processing, but this is often impractical. The degree to which differing protocols affect PERCIST classification is unclear. This study evaluates the consistency of PERCIST classification across different reconstruction algorithms and whether a proprietary software tool can harmonize SUV estimation sufficiently to provide consistent response classification. Methods: Eighty-six patients with non–small cell lung cancer, colorectal liver metastases, or metastatic melanoma who were scanned for therapy monitoring purposes were prospectively recruited in this multicenter trial. Pre- and posttreatment PET scans were acquired in protocols compliant with the Society of Nuclear Medicine and Molecular Imaging and the European Association of Nuclear Medicine (EANM) acquisition guidelines and were reconstructed with a point spread function (PSF) or PSF + time-of-flight (TOF) for optimal tumor detection and also with standardized ordered-subset expectation maximization (OSEM) known to fulfill EANM harmonizing standards. After reconstruction, a proprietary software solution was applied to the PSF ± TOF data (PSF ± TOF.EQ) to harmonize SUVs with the OSEM values. The impact of differing reconstructions on PERCIST classification was evaluated. Results: For the OSEMPET1/OSEMPET2 (OSEM reconstruction for pre- and posttherapeutic PET, respectively) scenario, which was taken as the reference standard, the change in SUL was −41% ± 25 and +56% ± 62 in the groups of tumors showing a decrease and an increase in 18F-FDG uptake, respectively. The use of PSF reconstruction affected classification of tumor response. For example, taking the PSF ± TOFPET1/OSEMPET2 scenario increased the apparent reduction in SUL in responding tumors (−48% ± 22) but reduced the apparent increase in SUL in progressing tumors (+37% ± 43), as compared with the OSEMPET1/OSEMPET2 scenario. As a result, variation in reconstruction methodology (PSF ± TOFPET1/OSEMPET2 or OSEM PET1/PSF ± TOFPET2) led to 13 of 86 (15%) and 17 of 86 (20%) PERCIST classification discordances, respectively. Agreement was better for these scenarios with application of the propriety filter, with κ values of 1 and 0.95 compared with 0.79 and 0.72, respectively. Conclusion: Reconstruction algorithm–dependent variability in PERCIST classification is a significant issue but can be overcome by harmonizing SULs using a proprietary software tool.