CSF3 and head and neck squamous cell carcinoma: Of note, in the general population (both, healthy and HNSCC) increased G-CSF levels in oral rinse (400 pg/ml or higher) predict the presence of Gram-negative pathogens with a specificity of 91% and a positive likelihood ratio of 8.4 (95% CI 2.64–26.71) (Fig. S1).