IL6 and neoplasm: Further, nonparametric Spearman's correlation revealed a significant positive correlation of IL-6 protein expression with the IL-6 mRNA expressions in the primary tumours of PTC patients (r = 0.333, P = 0.009), while no such association was observed with the IL-6 mRNA expression in adjacent normal tissues (r = −0.028, P = 0.833) (Table 5).