Nonmelanoma skin cancer is, by far, the most common type of cancer. There are two main types: squamous cell carcinoma and basal cell carcinoma. Skin cancers are most often caused by sun exposure, so they're likely to appear on the face, head, neck, shoulders, or back. Skin cancer symptoms can include a bump that is red or pearly white, or a patch of skin that bleeds, crusts over, or doesn't heal. This type of skin cancer is usually not life threatening, but should be treated promptly. Make sure to get any skin cancer symptoms checked by a doctor.