Carcinoma in situ of penis (Q39267)

This comprises both squamous carcinoma in situ and extramammary Paget disease of the penis. The former is an uncommon precancerous disease of penile skin. Lesions usually appear on the glans or inner aspect of the foreskin and are almost always found in uncircumcised men. If left untreated, 10-30% of cases develop into invasive squamous cell carcinoma of the penis. When it affects the skin of the shaft or prepuce it is commonly called Bowen disease. If it affects the glans or inner surface of the prepuce it may also be referred to as penile intraepithelial neoplasia (or in the past as erythroplasia of Queyrat). Extramammary Paget disease of penis is a rare form of carcinoma in situ involving penile skin or glans penis.