To this end, we examined S100A4 gene expression in 6 benign multinodular goitres (MNG) and 28 matched samples of adjacent normal thyroid tissue (N), primary (T) and metastatic (M) papillary thyroid carcinomas (PTC) by immunohistochemistry and real-time RT–PCR analysis. The gene discussed is S100A4; the disease is thyroid gland papillary carcinoma.