About 16% of diagnosed skin cancers are Squamous Cell Carcinoma (SCC). This cancer begins in the squamous cells, which are found in the upper layer of the epidermis. About 200,000 cases of SCC are diagnosed ever year. SCC tends to develop in fair-skinned middle-aged and elderly people who have had long-term sun exposure. It most often appears as a crusted or scaly area of skin with a red inflamed base that resembles a growing tumor, non-healing ulcer or crusted-over patch of skin. While most commonly found on sun-exposed areas of the body, it can develop anywhere, including the inside of the mouth and the genitalia. SCC may arise from actinic keratoses, which are dry, scaly lesions that may be skin-colored, reddish-brown or yellowish-black.