Squamous cell carcinoma of the skin occurs in the outermost part of the epidermis, or skin surface. Under a microscope, these cells appear flat. Like basal cell carcinoma, squamous cell carcinoma also develops on skin that is often exposed to the sun, such as skin on the head, neck and face.
Symptoms of Squamous Cell Carcinoma of the Skin
Squamous cell carcinoma sometimes develops from a precancerous skin growth called an actinic keratosis. It typically starts out as a small, red, painless lump or patch of skin that slowly grows and may ulcerate. It usually occurs on areas of skin that have been repeatedly exposed to strong sunlight.