Squamous cell carcinoma (SCC) is a prevalent form of skin cancer that arises from the squamous cells, which compose the outermost layer of the skin, the epidermis. These flat, thin cells are integral for maintaining the skin's protective barrier. SCC often develops in areas exposed to the sun, such as the face, ears, neck, hands, and forearms. Additionally, factors like prolonged sun exposure, a history of chronic skin inflammation, immunosuppression, and smoking can contribute to the risk of SCC.

The development of SCC is closely linked to ultraviolet (UV) radiation from the sun, which can induce mutations in cellular machinery. These mutations disrupt the normal regulatory processes, leading to the uncontrolled growth of squamous cells and the formation of precancerous (actinic keratoses) and cancerous lesions.

Typically, SCC presents as a persistent, scaly, or crusty bump or patch on sun exposed skin, which may bleed or become tender. Regular skin examinations and prompt reporting of any unusual changes to your board-certified dermatologist are vital for early detection. If a suspicious lesion is found, your dermatologist will perform a skin biopsy which will be evaluated by a dermatopathologist for diagnosis.

Treatment options for SCC are diverse, tailored to the specific characteristics of the tumor. Surgical excision is the gold standard approach, involving the removal of the cancerous tissue along with a margin of healthy skin to ensure complete elimination. Some subtypes of SCC are indolent and non-aggressive such as SCC in situ. These lesions can often be treated in a non-invasive manner, either with a cream such as 5-fluorouracil or a simple curettage procedure.

Mohs micrographic surgery is a specialized technique offering high precision and optimal tissue preservation, particularly in delicate areas like the face. This is the gold standard treatment for SCC in high risk areas such as the head and neck.

While SCC generally has a lower risk of metastasis overall, the risk increases with the size, location and depth of the tumor. Thus, early detection and treatment are essential to prevent local tissue destruction and cancer spread.

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