Basal cell cancer is the most common skin cancer. Lesions often appear on the face, ears, neck, trunk, or arms. Varying in color, these lesions may be waxy, pearly, scaly, or scarlike. Tiny blood vessels may be seen through the lesion's surface.

Melanoma is the most dangerous type of skin cancer. A melanoma lesion's borders are often poorly defined. It may be mixed in color. The shape and size of melanoma lesions tend to differ from one side to the other.

Paget's disease is a less common type of skin cancer. Lesions appear on only one breast. Or, they may form on the armpits or genitals. This disease takes the form of a scaly, reddish rash with sharp borders. The rash looks like dry skin, is firm to the touch, and is slightly raised. This rash does not clear up.

Squamous cell cancer is also a common type of skin cancer. Lesions often form on the face (commonly on the lips), ears, neck, hands, or arms. The lesions are firm, red bumps or flat, scaly, crusty growths.

Bowen's disease is an early stage of squamous cell cancer. The lesions are red, crusty, scaly growths with well-defined borders.