Figure 1.

Schematic representations of the most frequent histologic subtypes of penile human papillomavirus-related squamous cell carcinomas. (A) Basaloid carcinoma mainly composed of small, blue cells grouped in solid sheets, or nests with central abrupt keratinization or comedo-like necrosis; (B) Basaloid carcinoma with small, blue cells grouped in solid sheets and trabeculae; (C) Papillary basaloid carcinoma—variant of the basaloid with papillae lined by small, blue cells; (D) Papillary basaloid carcinoma—abrupt keratinization and invasive nests can be seen; (E) Warty carcinoma—papillomatosis and infiltrative nests composed of koilocytes and cells with ample eosinophilic or clear cytoplasm are the hallmark; (F) Warty-basaloid carcinoma—features of warty and basaloid carcinomas are seen in the same specimen.