As shown in Table 3, the circulating IL-6 levels were found to be significantly higher in male patients (P = 0.016) and in PTC patients having larger tumour size (P = 0.043), presence of metastasis (P < 0.001), and extrathyroidal extension of tumours (P = 0.019) when compared to their respective counterparts. This evidence concerns the gene IL6 and neoplasm.