Figure 3.

Histopathologic features of esthesioneuroblastoma: (A) solid tumor with prominent lobulated growth pattern with tumor lobules separated by fibrovascular septae (hematoxylin and eosin [H&E], ×100); (B) at higher magnification showing uniform small round blue tumor cells set in a neurofibrillary matrix; the fibrillary areas may be perivascular (arrows) (H&E, ×200); and (C) tumor cells without significant pleomorphism or mitotic activity; large collections of proliferative vessels can be a very prominent feature within the stroma (H&E, ×400).