CRP and cancer: Some of the available systemic inflammation indices involve patient-related factors; these indices include pretreatment C-reactive protein (CRP) levels, platelet-to-lymphocyte ratio (PLR), neutrophil-to-lymphocyte ratio (NLR), as well as the modified Glasgow prognostic score (mGPS) and can be applied as survival predictors in patients with various cancers (Brown et al., 2007; Crumley et al., 2006; Read et al., 2006), including head and neck cancer (Takenaka et al., 2018a, 2018b).