Immunohistochemical staining showed a Ki67 index of 8% in the tumour cells (Fig. 3b), strong and diffuse positivity for CD34 (Fig. 3c) and STAT6 (Fig. 3d), and zonal positivity for vimentin (Fig. 3d) and CD99 (Fig. 3f). Here, STAT6 is linked to neoplasm.