Immunohistochemical staining showed that the tumor cells were diffusely positive for NapsinA, TTF-1, and CK7 (Fig. 4 A 4B 4 C), and negative for Tg, WT-1, P63, P40, and CK20, and few cells showed a weak P53 staining. The gene discussed is WT1; the disease is neoplasm.