Among other immunostains not shown, ATRX nuclear expression was retained in all tumor cells, and none of the tumor cells were positive for IDH1 R132H mutant protein, napsin, NKX3.1, CD45, synaptophysin, INSM1, SOX10 protein, p40, CDX2 protein, PSAP, or PSA. The gene discussed is NKX3-1; the disease is neoplasm.