Skin Cancer refers to cancerous cell-growth that begins in the cells of the skin. It is by far the most common type of cancer. There are three main types of skin cancer, each named for the type of skin cell in which the cancer originates: basil cell cancer, squamous cell cancer, and melanoma.
Basil cell carcinomas, named for the cells in the bottom layer of the epidermis, are the most common type of skin cancer tumors and are the least dangerous of the three. Squamous cell carcinomas, named for the cells that are in the middle layer of skin, are less common but more dangerous than basil cells and more likely to spread. Melanoma, named for the melanocyte cells that create the pigment that gives skin its color, are the rarest type of skin cancer tumors, but are the most likely to spread and dangerous, and most likely to be fatal if left untreated.