Kaplan-Meier curves of progression-free survival (PFS) (a) and cause-specific survival (CSS) (b) in patients with HNC.

<p>Two groups with the accumulation of large (> 8.1, dotted lines) and small (≤ 8.1, solid lines) volumes of ¹⁸F-FDG were determined by metabolic-tumor-volume (MTV), one of the volume-based metabolic parameters. The two groups showed significant differences in PFS (<i>p</i> = 0.03) and CSS (<i>p</i> = 0.03). Three-year PFS and CSS rates were 70% and 73% for patients with a smaller metabolic volume (MTV ≤ 8.1), and 30% and 37% for those with a larger metabolic volume (MTV > 8.1), respectively.