Figure 2: (a) Case of Ewing's sarcoma with EWSR1 gene rearrangement (hematoxylin and eosin 200×); (b) strong nuclear expression of NKX2.2; (c) strong membranous expression of CD99; (d) case of olfactory neuroblastoma (hematoxylin and eosin 200×); (e) diffuse nuclear expression of NKX2.2; and (f) negative expression of CD99 in tumor cells