FIGURE 2.

A subset of nonoropharyngeal HPV-positive SCCs had a unique warty morphology with prominent exophytic growth (A, larynx). The surface of the tumors showed abundant production of hard orange parakeratin (B, oral cavity). Tumor cells demonstrated an abundant eosinophilic cytoplasm with marked nuclear pleomorphism and multinucleation (C, oral cavity). They were also notable for areas of koilocytic change and chromatin fragmentation (D, larynx). These warty tumors were diffusely positive for p16 (E, larynx) and HPV RNA ISH (F, larynx).