Pigmented Bowen's Disease

A 69-year-old man with a history of basal cell carcinoma of the face and back presented for a 6-month skin cancer evaluation. Physical examination revealed an asymmetric, irregularly pigmented, thin brown plaque of the anterior chest (A and B). A 3-mm punch biopsy specimen was obtained from a deeply pigmented area at the inferior border of the lesion to rule out melanoma.

Pathology studies demonstrated a thickened and disordered epidermis as well as multiple atypical epidermal cells with large, hyperchromatic nuclei. An inflammatory infiltrate was present in the upper dermis. These features are diagnostic for Bowen's disease.

This condition (also known as squamous cell carcinoma in situ) usually manifests as a solitary thin red plaque with some areas of scaling or crusting. Bowen's disease rarely appears as a thin pigmented plaque. The clinical differential diagnosis of Bowen's disease includes nummular eczema, psoriasis, superficial basal cell carcinoma, and melanoma. Bowen's disease of the glans penis (also called erythroplasia of Queyrat) appears as an eroded red plaque. A biopsy specimen should be obtained from any lesion thought to be psoriasis or eczema that does not respond to treatment.

Bowen's disease was thought to be a marker for internal malignancy until epidemiologic studies disproved this relationship. One setting where this association is seen, however, is arsenic exposure, which may lead to Bowen's disease, basal cell carcinoma, or visceral malignancies. Excisional surgery is the usual treatment.