ENO2 and neoplasm: Tumor tissue was collected and when sufficiently available, underwent H&E staining as well as immunohistochemistry analysis for a variety of known markers of sinonasal malignancies including p63 and cytokeratin and included known neuroendocrine markers of sinonasal malignancies including synaptophysin (SYP), neuron-specific enolase (NSE), and chromogranin.