Some experts in skin cancer regard Keratoacanthoma (KA) as a subtype of SCC, but with the difference that they may eventually resolve without treatment if left alone.

Melanoma is a less common form of skin cancer but can be one of the deadliest. Melanoma can form on any part of the body but most often forms on sun exposed areas such as the arms, legs and face.

Basal Cell Carcinoma (BCC) is the most common form of skin cancer. It is derived from the basal or deepest layers of the epidermis (outer layer of skin).

Squamous Cell Carcinoma (SCC) is the second most common skin cancer, and often occur in elderly people who have had extensive sun exposure over their lifetimes.