The primary cause of basal carcinoma is ultraviolet rays from tanning sunlamps or the sun. These rays damage the DNA in skin cells, causing cancer, as WebMD explains. The risk factors for basal carcinoma include previous skin cancers, a family history of this condition, light-colored skin and hair, and exposure to chemicals such as arsenic, according to Healthline.
Basal carcinoma is a skin cancer that develops on parts of the skin that are largely exposed to the sun, such as the face and neck, states Mayo Clinic. The tumor appears as a small bump on the face, but it can appear on other body parts, such as the legs, arms and trunk. When a skin surface is exposed to the sun for long, the ultraviolet rays damage the DNA in the skin cells, causing this cancer. However, basal carcinoma grows very slowly and takes many years before its symptoms show up, notes WebMD.
A person whose close relative had skin cancer is more likely to develop basal carcinoma. Medications that weaken the immune system and exposure to toxic metals can also result in this condition. Moreover, spine abnormalities and some inherited syndromes associated with skin cancer, such as nevoid basal cell carcinoma syndrome, can also cause basal carcinomas, according to Mayo Clinic.