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Which skin changes can occur before squamous cell carcinoma develops?

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skin rash caused by Lyme disease — skin disease Visible alterations in the texture of the skin, such as rashes and hives, can be indicative of serious disease. For example, one of the first signs of Lyme disease is a circular rash in a bull's-eye pattern on the skin.

Before squamous cell carcinoma develops, the most common premalignant or precancerous skin lesion that appears is actinic keratosis.1

These lesions typically manifest as rough, scaling, red or brown papules. They are most frequently found on areas of the body that have experienced significant sun exposure over time, such as the ears, forehead, bald scalp, and the back of the hands.12

Early detection and clinical inspection are vital, as physicians look for changes in skin lesions—such as recent enlargement, irregular outlines, darkening, or bleeding—that may indicate the progression toward cancer. Actinic keratosis can be effectively managed and removed through medical procedures such as cryotherapy, surgical excision, or electrodesiccation.1