What Causes Squamous Cell Carcinoma?

Repeated ultraviolet exposure from sunlight or tanning equipment can damage the DNA that controls skin-cell growth. Risk can also be influenced by previous radiation or chronic wounds, long-standing inflammation, certain viral infections, and a weakened immune system. Actinic keratosis and Bowen's disease are abnormal changes in the outer skin that may be associated with squamous cell carcinoma. It can occur on sun-exposed or covered skin, so a new rough, scaly, crusted, tender, or bleeding area should not be dismissed because it is small.

Check your skin regularly, including the scalp, ears, lips, hands, and areas covered by clothing. Use shade, protective clothing, and broad-spectrum sunscreen as practical, and avoid tanning devices. Do not repeatedly pick or self-treat a persistent scaly patch. A clinician may examine the area with magnification and, when needed, take a small sample to confirm the diagnosis before discussing treatment.

Book a prompt skin assessment for a sore that does not heal, a rough patch that keeps returning, a growth that enlarges, or a lesion that bleeds, crusts, becomes tender, or changes in appearance. Seek earlier review if you have reduced immune function, a chronic wound, or a history of skin cancer. Rapid growth, severe pain, or involvement of the eye, nose, ear, or lip also needs timely attention.

Could this lesion be an actinic keratosis, Bowen's disease, or another condition? Does it need a biopsy? How should I protect the surrounding skin and monitor for new changes?