How Skin Cancer Is Caused

Sun

Ultraviolet radiation (UV) from the sun can damage DNA, the building of genetic material, and the overall health of skin cells. These UV rays cause suntan and sunburn. Prolonged exposure to the sun can lead to premature skin aging and skin cancer. Some research indicates that intermittent sun exposure during the summer months or on vacation, especially in the younger years, can cause certain skin cancers, according to the National Institutes of Health. Abnormal genes may be passed on from one generation to the next, increasing the likelihood of getting skin cancer.

Mutations

Sun exposure of normal skin may result in mutations that start skin cells on a path toward cancer. People with a rare inherited disorder called xeroderma pigmenosum are very sensitive to sun exposure, which may increase their risk of developing skin cancer about a thousand times more than the general population. Light-skinned Caucasians are at high risk.

Tumors

Sun exposure promotes tumors by damaging cells normally protected by tumor protectors. It slows down the cell cycle that repairs DNA damage, turning the cells into unrepaired DNA. The cells become defective, making them more vulnerable to UV radiation even at lower doses.

Over Time

The damaged skin-cell mutations occur very early in the skin cancer process of sun-exposed skin. Most of these cells die over time, but the ones that survive can lead to skin cancers after long periods of exposure to the sun. Most skin cancers appear after age 50. But doctors stress that protection from the sun should start in childhood because the damaging effects begin at an early age.

Types

There are three main types of skin cancer. Basal cell carcinoma grows slowly and is the least dangerous, as long as it is treated early. Squamous cell carcinoma is more serious because it can spread to vital organs in the body. Malignant melanoma is the deadliest form of skin cancer as it can spread rapidly from the skin to the internal organs. Scientists are not exactly sure what causes melanoma. The sun may be a factor, but so are age, family history and a weakened immune system.

Other Factors

Exposure to ultraviolet radiation in tanning booths can also increase the risk of skin cancer. Therapeutic radiation for patients with other cancers may also be one cause of skin cancer.