Onset of multiple basal cell carcinoma 60 years after X-ray treatment for tinea capitis.

Basal cell carcinoma is a malignant tumour of the skin that is often localized and rarely diffuse. It is the most common cancer of white populations and rare in blacks. An increased incidence is seen in subjects with acquired immunodeficiency syndrome (AIDS) and in individuals receiving immunosuppressive drugs following organ transplantation. Although exposure to ultraviolet (UV) light has long been accepted as the main risk factor for basal cell carcinoma, the precise relationship is unclear. Evidence that ionizing radiation is carcinogenic for humans comes from reports of nonmelanoma skin cancers in several radiation-exposed groups. Radiologists and subjects treated with X-rays have an increased risk for development of skin cancer. Therapeutic radiation used for benign dermatoses, including psoriasis, eczema and tinea capitis, may lead to onset of basal cell carcinoma many decades later. A 72-year-old woman was referred to our dermatology department for multiple superficial basal cell carcinomas that had developed on her scalp over the previous 2 years. When she was 13 years old the woman had undergone X-ray epilation of the scalp to treat tinea capitis.