CA9 and neoplasm: For HPV positive tumors, the following multiple regression model was obtained; T = −7.3 + 0.62 × WISP1 + 0.44 × CXCL10 + 0.39 × CCL7 − 0.3 × ICOSLG + 0.27 × CA9 − 0.27 × IL-18 + 0.18 × VEGFA − 0.15 × FRα − 0.073 × CD207 + 0.064 × TCL1A + 0.04 × CX3CL1, where the protein names denote the respective expression variables, T is the ‘tumor/normal’ status, and the first term is the intercept of the linear equation.