Basal Cell Carcinoma Characteristics and Risk Factors

Clinical Presentations

The British Journal of Dermatology describes basal cell carcinoma (BCC) as a slow-growing, locally invasive lesion that may ulcerate centrally, with diverse morphological presentations including nodular, cystic, superficial, morphoeic (sclerosing), keratotic and pigmented variants 1, 2
BCC frequently develops on sites previously exposed to radiation (either sun or therapeutic), according to the Journal of the National Comprehensive Cancer Network 3
The National Comprehensive Cancer Network notes that basosquamous carcinoma exhibits features of both BCC and squamous cell carcinoma, with higher metastatic potential than typical BCC 4

The American Academy of Dermatology identifies poorly defined clinical margins, rapid growth of the lesion, and neurologic symptoms as warning signs of aggressive BCC behavior 5, 6, 7
Lesions in high-risk locations (central face, eyelids, eyebrows, periorbital skin, nose, lips, chin, mandible, ears) and recurrent lesions in previously treated areas are also associated with aggressive behavior 5, 6

The National Comprehensive Cancer Network notes that fair skin, red or blond hair, and light eye color are risk factors for BCC, in addition to history of extensive sun exposure, especially in childhood, and increasing age 1, 3
Immunosuppression and previous radiation therapy are also identified as risk factors by the American Academy of Dermatology and the National Comprehensive Cancer Network 1, 3, 6

The National Comprehensive Cancer Network warns that BCC rarely metastasizes (less than 0.1%) but can cause substantial local destruction and disfigurement if left untreated, and that histologic subtypes with aggressive growth patterns are more likely to recur than nodular and superficial types 1, 3, 7, 8
Basosquamous carcinomas have metastatic capacity more similar to squamous cell cancer than typical BCC, according to the National Comprehensive Cancer Network 4, 7