Optimal respiratory-gated [18F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma

Esther M M Smeets; Dominique S Withaar; Willem Grootjans; John J Hermans; Kees van Laarhoven; Lioe-Fee de Geus-Oei; Martin Gotthardt; Erik H J G Aarntzen

doi:10.1186/s13550-019-0492-y

Optimal respiratory-gated [¹⁸F]FDG PET/CT significantly impacts the quantification of metabolic parameters and their correlation with overall survival in patients with pancreatic ductal adenocarcinoma

EJNMMI Res. 2019 Mar 13;9(1):24. doi: 10.1186/s13550-019-0492-y.

Authors

Esther M M Smeets¹, Dominique S Withaar², Willem Grootjans³, John J Hermans¹, Kees van Laarhoven⁴, Lioe-Fee de Geus-Oei^{3

5}, Martin Gotthardt¹, Erik H J G Aarntzen⁶

Affiliations

¹ Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein-Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands.
² Department of Radiology, Medisch Spectrum Twente, Enschede, The Netherlands.
³ Department of Radiology, Leiden University Medical Center, Leiden, The Netherlands.
⁴ Department of Surgery, Radboud University Medical Center, Nijmegen, The Netherlands.
⁵ Biomedical Photonic Imaging Group, University of Twente, Enschede, The Netherlands.
⁶ Department of Radiology and Nuclear Medicine, Radboud University Medical Center, Geert Grooteplein-Zuid 10, PO Box 9101, 6500 HB, Nijmegen, The Netherlands. [email protected].

Abstract

Purpose: Metabolic parameters are increasingly being used to characterize tumors. Motion artifacts due to patient respiration introduce uncertainties in quantification of metabolic parameters during positron emission tomography (PET) image acquisition. The present study investigates the impact of amplitude-based optimal respiratory gating (ORG) on quantification of PET-derived image features in patients with pancreatic ductal adenocarcinoma (PDAC), in correlation with overall survival (OS).

Methods: Sixty-nine patients with histologically proven primary PDAC underwent 2'-deoxy-2'-[¹⁸F]fluoroglucose ([¹⁸F]FDG) PET/CT imaging during diagnostic work-up. Standard image acquisition and reconstruction was performed in accordance with the EANM guidelines and ORG images were reconstructed with a duty cycle of 35%. PET-derived image features, including standard parameters, first- and second-order texture features, were calculated from the standard and corresponding ORG images, and correlation with OS was assessed.

Results: ORG significantly impacts the quantification of nearly all features; values of single-voxel parameters (e.g., SUV_max) showed a wider range, volume-based parameters (e.g., SUV_mean) were reduced, and texture features were significantly changed. After correction for motion artifacts using ORG, some features that describe intra-tumoral heterogeneity were more strongly correlated to OS.

Conclusions: Correction for respiratory motion artifacts using ORG impacts the quantification of metabolic parameters in PDAC lesions. The correlation of metabolic parameters with OS was significantly affected, in particular parameters that describe intra-tumor heterogeneity. Therefore, interpretation of single-voxel or average metabolic parameters in relation to clinical outcome should be done cautiously. Furthermore, ORG is a valuable tool to improve quantification of intra-tumoral heterogeneity in PDAC.

Keywords: Metabolic parameters; Optimal respiratory gating; Pancreatic ductal adenocarcinoma; Texture features; [18F]FDG PET/CT.

Grants and funding

KUN2015-8106/KWF Kankerbestrijding