Title: Selected PET radiomic features remain the same
Abstract: // Tetsuya Tsujikawa 1 , Hideaki Tsuyoshi 2 , Masafumi Kanno 3 , Shizuka Yamada 2 , Masato Kobayashi 4 , Norihiko Narita 3 , Hirohiko Kimura 5 , Shigeharu Fujieda 3 , Yoshio Yoshida 2 and Hidehiko Okazawa 1 1 Biomedical Imaging Research Center, University of Fukui, Fukui, Japan 2 Department of Obstetrics and Gynecology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 3 Department of Otolaryngology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan 4 Wellness Promotion Science Center, College of Medical, Pharmaceutical and Health Sciences, Kanazawa University, Kanazawa, Japan 5 Department of Radiology, Faculty of Medical Sciences, University of Fukui, Fukui, Japan Correspondence to: Tetsuya Tsujikawa, email: [email protected] Keywords: PET radiomic features; PET/CT; PET/MR Received: November 27, 2017 Accepted: March 24, 2018 Published: April 17, 2018 ABSTRACT Purpose: We investigated whether PET radiomic features are affected by differences in the scanner, scan protocol, and lesion location using 18 F-FDG PET/CT and PET/MR scans. Results: SUV, TMR, skewness, kurtosis, entropy, and homogeneity strongly correlated between PET/CT and PET/MR images. SUVs were significantly higher on PET/MR 0-2 min and PET/MR 0-10 min than on PET/CT in gynecological cancer ( p = 0.008 and 0.008, respectively), whereas no significant difference was observed between PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min images in oral cavity/oropharyngeal cancer. TMRs on PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min increased in this order in gynecological cancer and oral cavity/oropharyngeal cancer. In contrast to conventional and histogram indices, 4 textural features (entropy, homogeneity, SRE, and LRE) were not significantly different between PET/CT, PET/MR 0–2 min , and PET/MR 0–10 min images. Conclusions: 18 F-FDG PET radiomic features strongly correlated between PET/CT and PET/MR images. Dixon-based attenuation correction on PET/MR images underestimated tumor tracer uptake more significantly in oral cavity/oropharyngeal cancer than in gynecological cancer. 18 F-FDG PET textural features were affected less by differences in the scanner and scan protocol than conventional and histogram features, possibly due to the resampling process using a medium bin width. Methods: Eight patients with gynecological cancer and 7 with oral cavity/oropharyngeal cancer underwent a whole-body 18 F-FDG PET/CT scan and regional PET/MR scan in one day. PET/MR scans were performed for 10 minutes in the list mode, and PET/CT and 0–2 min and 0–10 min PET/MR images were reconstructed. The standardized uptake value (SUV), tumor-to-muscle SUV ratio (TMR), skewness, kurtosis, entropy, homogeneity, short-run emphasis (SRE), and long-run emphasis (LRE) were compared between PET/CT, PET/MR 0-2 min , and PET/MR 0-10 min images.