10.1371/journal.pone.0155635.g003 Tetsuya Tsujikawa Tetsuya Tsujikawa Satoko Asahi Satoko Asahi Myungmi Oh Myungmi Oh Yoshitaka Sato Yoshitaka Sato Norihiko Narita Norihiko Narita Akira Makino Akira Makino Tetsuya Mori Tetsuya Mori Yasushi Kiyono Yasushi Kiyono Tatsuro Tsuchida Tatsuro Tsuchida Hirohiko Kimura Hirohiko Kimura Shigeharu Fujieda Shigeharu Fujieda Hidehiko Okazawa Hidehiko Okazawa Kaplan-Meier curves of progression-free survival (PFS) for <sup>62</sup>Cu-ATSM PET (a) and <sup>18</sup>F-FDG PET (b) in patients with HNC. Public Library of Science 2016 18 F-FDG threshold TMR ATSM SUV ATSM ROC analysis RTV CSS 18 F-FDG PET scans PSF 62 Cu-ATSM PET 18 F-FDG PET 62 Cu-ATSM Tumor Redox Status HNC patient outcomes TLR TLG tumor-to-muscle activity concentration ratios 62 Cu-ATSM PET Purpose Tumor redox MTV II PFS Conclusion Tumor redox parameters pretreatment 62 Cu-ATSM 2016-05-17 21:18:42 Figure https://plos.figshare.com/articles/figure/Kaplan-Meier_curves_of_progression-free_survival_PFS_for_sup_62_sup_Cu-ATSM_PET_a_and_sup_18_sup_F-FDG_PET_b_in_patients_with_HNC_/3939063 <p>Two groups of high (dotted lines) and low (solid lines) tracer accumulation were determined by each cut-off value of the tumor-to-muscle ratios (TMR<sub>ATSM</sub> and TMR<sub>FDG</sub>). TMR<sub>ATSM</sub>, one of the intensity-based redox parameters, showed a significant difference in PFS between two groups (<i>p</i> = 0.03), whereas TMR<sub>FDG</sub>, one of the intensity-based metabolic parameters, did not (<i>p</i> = 0.15). The three-year PFS rate was 74% for patients with lower accumulation tumors (TMR<sub>ATSM</sub> ≤ 3.2) and 29% for those with over-reductive tumors (TMR<sub>ATSM</sub> > 3.2).</p>