Squamous cell skin carcinoma usually appears as a tiny, painless bump or patch. The skin around it can be red and swollen. The cancer itself can be scaly, crusty, or wartlike. It can have an open sore in the center.
Although squamous cell carcinoma can develop on any part of the body, the most common spots are the:
head, including the scalp, lips, ears, and mouth
Back of the hands and the arms.