Immunohistochemistry corresponds to typical sex cord-stromal tumour profile (positivity for SF1, calretinin, inhibin, vimentin, often FOXL2; often oestrogen and progesterone receptor expression; and negativity or weak patchy staining for keratin, negativity for EMA, PAX8, and PAX2) (Fig. 2). The gene discussed is PAX2; the disease is neoplasm.