Squamous cell carcinoma (SCC or SqCC), also known as squamous cell cancer, is one of the main types of skin cancer that begins from squamous cells in the skin. Cancers that involve the anus, cervix, head and neck, and vagina are also most often squamous cell cancers. The esophagus, urinary bladder, prostate, and lung are other possible sites. Frequent exposure to direct, strong sunlight without adequate sunscreen protection is a risk factor for skin cancer. Despite sharing the name squamous cell carcinoma, the SCCs of different body sites can show differences in their presenting symptoms, natural history, prognosis, and response to treatment. SCC typically occurs in people older than 50 years. As of 2014 an increasing number of people in their 20s and 30s are being affected. It is twice as common in men as in women. People with darker skin and eyes have a lower risk than individuals with lighter colored skin. People with fair skin, light hair and eyes are at highest risk of developing the disease.