PMC3368184_01
Preoperative computed tomography (a), and magnetic resonance images ((b) coronal, (c) sagittal, and (d) axial) show a cystic mass extending from the left olfactory cleft to the olfactory groove. An endoscopic image (e) shows the tumor extending from the olfactory cleft to the middle meatus (arrowheads). MT: middle turbinate. Magnetic resonance images two years after operation show no recurrence of tumors (f)-(h).
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fig1
Computed tomography (CT) displayed a lesion at the olfactory cleft that extended superiorly to the olfactory groove, with a bone defect in the skull base (Figure 1(a)). Magnetic resonance imaging (MRI) revealed a mass showing cystic changes (Figures 1(b)-1(d)), with solid portions demonstrating strong postgadolinium contrast enhancement. Under general anesthesia, the uncinate process in the left nostril was removed to expose the tumor in the middle meatus (Figure 1(e)). The patient had an uneventful postoperative course, and no further recurrence was detected during the 2-year follow-up period (Figures 1(f)-1(h)).
Hematoxylin and eosin (HE) staining shows that the tumor is composed of spindle cells with eosinophilic cytoplasm (a). Immunohistochemistry demonstrates that the tumor is strongly positive for S100 (b) and neuron-specific enolase (NSE, (d)), weakly positive for synaptophysin (SYN, (f)), and is negative for Leu7 (c) and epithelial membrane antigen (EMA, (e)). In immunohistochemistry, nuclear staining with hematoxylin was performed. Scale bar in (f) represents 50 mum for (a)-(f).
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fig2
Microscopic examination of the resected tumor demonstrated a neoplasm composed of spindle cells with eosinophilic cytoplasms and elongated or wavy nuclei with occasional symplastic changes (Figure 2(a)). Immunohistochemically, the spindle cells were diffusely positive for S-100 protein, neuron-specific enolase, and synaptophysin (Figures 2(b), 2(d), and 2(f)), and negative for epithelial membrane antigen (Figure 2(e)), which also supported the diagnosis of schwannoma, although Leu7 was completely negative (Figure 2(c)).