The most common form of sun damaged lesion is a sun spot or solar keratosis. These occur in sun exposed areas. They do have an increased risk of turning into skin cancer but this is rather small, being about 1 in 100 to 1 in 200. These skin abnormalities can be treated with creams or by freezing with liquid nitrogen.
The most common form of skin cancer is the basal cell carcinoma, which accounts for about 90% of all skin cancers. These occur mainly in sun exposed areas and appear as red ulcerated or bleeding moles. These skin cancers do not spread to other parts of the body and removal by excision or curettage is often the treatment of choice. Once removed these are then checked by a pathologist. Some skin cancers such as superficial basal cell carcinoma can be treated with special creams but the efficacy of treatment is low as compared to surgical treatments.
A more dangerous form of skin cancer is the squamous cell carcinoma and represents about 8% of all skin cancers. These need to be excised (cut out) and examined by a pathologist. There is a chance that these can spread but this is less likely if they are removed early.
A very dangerous form of skin cancer is the melanoma which is produced from skin pigment cells. These have an increased tendency to spread even when they are fairly thin and rapid identification and removal is suggested and essential. In melanomas that have spread over recent times, very successful immune therapies have been developed to treat them. Many very early melanomas may be completely cured if removed early.
Please check the links below for more information on various types of skin cancers.