If actinic keratosis is not treated, it can progress into which type of cancer?

Actinic keratosis is a precancerous skin condition that arises due to prolonged exposure to ultraviolet (UV) radiation from the sun or artificial sources. The primary concern with untreated actinic keratosis is its potential progression to squamous cell carcinoma (SCC). The lesions typically present as rough, scaly patches on sun-exposed skin, and while many may not progress, a significant percentage can develop into invasive squamous cell carcinoma if left untreated.

The link between actinic keratosis and squamous cell carcinoma is well-established; SCC is known to arise from previously damaged keratinocytes, which are the cells primarily affected in actinic keratosis. Early intervention, such as cryotherapy, topical treatments, or photodynamic therapy, can help prevent such progression.

In contrast, basal cell carcinoma, melanoma, and Kaposi's sarcoma arise from different types of skin cells or have different etiologies, making them less relevant in the context of actinic keratosis. Specifically, basal cell carcinoma typically originates from the basal layer of the epidermis and is not directly linked to the progression from keratotic lesions. Melanoma, while a serious skin cancer, predominantly arises from melanocytes, the pigment-producing cells, and is