It is most commonly seen in older individuals on sun-exposed areas of the skin and typically appears as a red nodule with surface keratinization or as a non-healing ulcer. Differentiating between basal cell carcinoma and squamous cell carcinoma can often be difficult, as their external appearance may be very similar.
Squamous cell carcinoma frequently develops in areas with pre-existing precancerous lesions, such as actinic keratosis, keratoacanthoma, and Bowen’s disease. In general, it is more aggressive than basal cell carcinoma and can metastasize in approximately 10%–30% of cases.

Treatment should be aggressive and is generally similar to that of basal cell carcinoma. Because SCC is more aggressive, wider surgical margins are recommended, along with stricter criteria when considering less invasive treatment methods.
Approximately 95% of local recurrences and metastases occur within the first five years. Therefore, regular long-term postoperative follow-up is essential, typically every 3–6 months for five years, in order to allow early detection of recurrences and metastases.