Fig. 2: Morphologic variants and p16 expression in PEIN.

A PeIN, warty-basaloid variant. Warty features are present on the surface (B), while basaloid features are seen in the lower layers (C). P16 stain spares the upper keratinizing layer (D). This lesion was positive for HR-HPV16 (Magnification, A and D, X100; B and C, X200).