Carcinoma in situ of penis

This code signifies the presence of non-invasive malignant cells confined to the epithelial layer of the penis, without evidence of invasion into the underlying stroma. It represents an early stage of penile cancer, often referred to as Bowen's disease or erythroplasia of Queyrat when affecting specific penile sites.

Apply this code when documentation explicitly states "carcinoma in situ of penis," "Bowen's disease of penis," or "erythroplasia of Queyrat." This diagnosis is typically confirmed by biopsy showing intraepithelial neoplasia without stromal invasion.

• Differentiate from invasive penile carcinoma (187.x) which involves stromal invasion.
• Ensure the documentation specifies "in situ" to avoid miscoding a more advanced malignancy.
• Consider additional codes for any associated symptoms or risk factors, such as HPV infection (079.4).