Which skin condition can become squamous cell carcinoma if left untreated?

Actinic keratosis is considered a precancerous skin condition that can develop into squamous cell carcinoma if not appropriately addressed. It typically manifests as rough, scaly patches on areas frequently exposed to the sun, such as the face, ears, lips, back of the hands, forearms, and scalp. The abnormal growth of keratinocytes, the primary cells in the outer layer of the skin, characterizes this condition.

If left untreated, the DNA damage caused by ultraviolet (UV) radiation can lead these cells to become cancerous, culminating in squamous cell carcinoma, which is a more aggressive form of skin cancer. Early intervention, such as cryotherapy, topical treatments, or photodynamic therapy, can effectively prevent the progression from actinic keratosis to skin cancer, underscoring the importance of regular skin checks and treatments for sun-damaged skin.

The other options listed—psoriasis, ichthyosis, and seborrheic dermatitis—do not carry the same risk of progression to squamous cell carcinoma, making actinic keratosis the notable exception that highlights the necessity for monitoring potentially precancerous conditions.