Basal cell carcinoma is the most common. While not usually life-threatening, if allowed to grow it can spread to underlying tissues and destroy them. These cancers often appear as a small shiny bump or nodule that may bleed easily. Squamous cell carcinoma may appear as nodules of red, itchy patches with well-defined outlines. It can spread to other parts of the body and destroy tissue more readily than the basal cell carcinoma and can grow quite large if untreated.
Malignant melanoma is the least common and the most lethal of the major skin cancers.
Melanoma involves the cells that give skin its color. As a result melanomas are often black or brown spots, like moles. If not treated promptly, melanoma can spread throughout the body. Watch for signs of cancer on the face, tips of the ears, hands and forearms. The shoulders, back and lower legs are also likely candidates.