A Case of Sebaceous Carcinoma Arising from Bowen's Disease

Bowen’s disease is an intraepidermal squamous cell carcinoma. Although an invasive squamous cell carcinoma occasionally develops from Bowen’s disease, the development of sebaceous carcinoma from Bowen’s disease is very rare. We report a case of sebaceous carcinoma arising from Bowen’s disease occurring on the cheek in a 72-year-old female. She presented with a crust and erythematous scaly papule on the face. Histopathologic examination of the crusted lesion showed atypical tumor cells with large, hyperchromatic nuclei and frequent mitoses in the epidermis suggesting of Bowen’s disease. However, the scaly papule showed tumor lobule composed of clear cells with foamy cytoplasm and atypical undifferentiated cells suggesting of sebaceous carcinoma. CK7 staining was positive only for the tumors cells of the specimen from the scaly papule. The positive staining of CK7 may help distinguish sebaceous carcinoma from clear cell squamous cell carcinoma when that distinction can not be clearly made by light microscopy alone.