In the LSCC patients, the plasma IL-10 concentrations (24.47±5.4 pg/ml) were significantly higher compared with those in the controls (19.02±7.01 pg/ml; P<0.01) and the vocal leukoplakia patients (20.33±3.1 pg/ml; P=0.001), although the concentrations in the vocal leukoplakia patients were also higher than those in the controls. Here, IL10 is linked to leukoplakia.