Basal cell carcinoma is a common skin tumor.
The predisposing factors include sun exposure, xerodermal pigmentosum, immunosuppression and basal cell nevus syndrome. This syndrome is inherited as a dominant disease and is characterized by organ anomalies in the bone, nervous system, eye and reproductive organs and numerous basal cell carcinomas early in life.
Tumor usually appears in the sun exposed areas of the body.
Grossly, the tumor appears as a pearly papule, expansile plaque, pigmented lesion or as ulcer.
Microscopically, the tumor consists of islands of basal cells which show peripheral palisading. Some basal cell carcinomas show evidence of keratinization (keratotic basal cell carcinoma), are pigmented or appear as multifocal superficial lesions. The tumor islands show artefactual separation from the stroma.