Immunohistochemically, the tumor was positive for vimentin, epithelial membrane antigen (EMA), cytokeratin (CK), CK7 and neuron specific enolase (NSE); and negative for CK34BE12, synapsin (Syn), CK20, cluster of differentiation 56 (CD56), CD10, Wilm’s tumor-1 (WT-1), CD34, CD57, P53, CD99, thyroid transcription factor-1 (TTF-1), CD15 and thyroglobulin (TG); and had a Ki-67 labeling index (LI) of 30%. The gene discussed is CD99; the disease is neoplasm.