Leukoplakia penis and balanitis xerotica obliterans are precancerous lesions. Bowen's disease, erythroplasia (Queyrat), and extramammary Paget's disease are carcinomas in situ. Lesions of both types may closely mimic benign skin conditions that may occur in the genital region. Histologic examination is usually the only certain means of diagnosis. The same considerations apply to pseudomalignancies, e.g., giant condyloma acuminatum (Buschke-Loewenstein), which clinically behaves as a carcinoma but histologically appears benign, and Bowenoid papulosis, a new entity that is believed to be benign although it has histologic features of a carcinoma in situ.