Squamous Cell Carcinoma Squamous cell carcinoma accounts for about 20 percent of all skin cancers. Although more aggressive than basal cell carcinoma, this cancer is highly treatable. Squamous cell carcinoma, which starts in the middle layer of the epidermis, looks like a red, scaly area of skin. Squamous cell carcinoma eventually becomes an open sore. Although more rare, this cancer is the most deadly, accounting for approximately 79 percent of all skin cancer deaths.
Malignant melanoma starts in the melanocytes, skin cells that produce pigment in the skin.
Malignant melanomas usually start out as moles that then turn cancerous. This type of skin cancer is likely to spread rapidly. The sun emits light, infrared, and ultraviolet rays. Ultraviolet rays are invisible, but they can pass deep into the skin. Other sources of UV radiation include sunlamps and tanning beds.