A carcinoma arising from the squamous cells of the epidermis. Skin squamous cell carcinoma is most commonly found on sun-exposed areas. The majority of the tumors are well-differentiated. The disease is Monarch Disease Ontology entry MONDO_0002529 (skin squamous cell carcinoma). Also known as: cutaneous squamous cell carcinoma, epidermoid carcinoma of skin, epidermoid carcinoma of the skin, epidermoid skin carcinoma, skin squamous cell cancer, squamous cell carcinoma - skin, squamous cell carcinoma of skin, squamous cell carcinoma of the skin.