STAP1 and chronic hepatitis: Since our validation test indicated that STAP1 effectively discriminated between either healthy controls or chronic hepatitis and early stages of HCC, we further validated association of STAP1 methylation with stages 1 and 2 HCC in T cell DNA derived from a third independent cohort (n = 48) of healthy controls (n = 16) HepB (9) and HCC stages 1 (n = 11) and 2 patients (n = 12) (Additional file 15: Table S14).