Figure 3F+I shows cases of and PTCs with an extensive intracellular pendrin expression, and Figure 3G+J illustrates follicular and papillary carcinomas with moderate pendrin expression. The pattern of reactivity was confirmed for all tissues analysed by confocal fluorescent microscopy (Figure 3D – Graves' tissue; H – FTC; K+L – PTC carcinomas). There was no relationship between pendrin expression or pendrin localisation and tumour stages (TNM), or tumour size (Table 2). This evidence concerns the gene SLC26A4 and carcinoma.