In the same subgroup, both the IL-17F level and the IFN-γ/IL-17F ratio discriminated CIS from MS, RRMS, and PPMS (IL-17F: AUC = 0.87, 0.89, and 0.89, respectively; IFN-γ/IL-17F: AUC = 0.91, 0.93, and 0.89, respectively). This evidence concerns the gene IL17F and in situ carcinoma.