What causes basal cell carcinoma?

Basal cells sit in the outer layer of the skin. Repeated ultraviolet exposure from sunlight or tanning devices can damage their genetic instructions, and the altered cells may continue multiplying instead of following normal growth controls. Cumulative exposure matters, so a lesion can appear years after earlier sun damage. Light skin, a history of intense exposure, previous radiation, immune suppression and certain inherited traits can increase susceptibility, but anyone can develop a suspicious lesion. Basal cell carcinoma often appears on sun-exposed areas as a shiny bump, a sore that does not heal, or a patch that crusts and bleeds.

Use shade, protective clothing, a hat and broad-spectrum sunscreen on exposed skin. Avoid tanning devices and check your skin regularly, including the ears, scalp and backs of the hands. Do not repeatedly cover a changing sore with makeup or pick its crust. A clinician may examine the area with magnification and take a sample if needed. Confirmed basal cell carcinoma is usually managed with a procedure chosen for its size, site and microscopic features.

Arrange a dermatology review for a sore that does not heal, a pearly or shiny growth, a repeatedly bleeding crust, or a scar-like pale area that is enlarging. Seek earlier assessment if the change is near an eye, nose or ear, or if it becomes painful or ulcerated. A suspicious mark does not prove cancer, but examination is the safe way to identify it and plan treatment if necessary.

Ask what features make the lesion concerning, whether a biopsy is needed, and which treatment would protect nearby structures. Ask how the area will heal, how to monitor the rest of your skin and how to reduce further ultraviolet damage.