A superficial layer of benign ciliated columnar epithelia focally overlies multiple layers of dysplastic cells underneath, an observation in support of a pre-existing inverted Schneiderian papilloma.

• 下层的多层异型细胞之上，局灶性被覆良性纤毛柱状上皮，此观察支持先前存在内翻性乳头状瘤。