Melanoma - The Skin Cancer

Skin cancers include melanoma, basal cell, and squamous cell. Basal and squamous cell are common and treatment is very effective; malignant melanoma, especially in later stages of melanoma, is serious and treatment is difficult. Sun exposure is the biggest cause of melanoma and other skin cancers, but early diagnosis and treatment can increase the survival rate from melanoma. The number of new cases of skin cancer appears to be increasing each year. The number of deaths due to skin cancer, however, is fairly small.

Melanoma is a form of skin cancer that begins in melanocytes (the cells that make the pigment melanin). Some melanomas may develop from moles, but most do not. Moles are very common. Most people have between 10 and 40 moles. If you have many moles, a careful, routine exam by your doctor or a dermatologist, along with monthly skin self-exams may be recommended.

A person may develop new moles from time to time, usually until about age 40. Moles can be flat or raised. They are usually round or oval and no larger than a pencil eraser. Many moles begin as a small, flat spot and slowly become larger in diameter and raised. Over many years, they may flatten again, become flesh-colored, and go away.

No one knows the exact causes of melanoma. However, research has shown that people with certain melanoma risk factors are more likely than others to develop melanoma. People who have had at least one severe, blistering sunburn as a child or teenager are at increased risk of melanoma. People whose immune system is weakened by certain cancers, by drugs given following organ transplantation, or by HIV are at increased risk of developing melanoma.

Melanoma sometimes runs in families. Having two or more close relatives who have had this disease is a risk factor. About 10% of all patients with melanoma have a family member with this disease. Melanoma occurs more frequently in people who have fair skin that burns or freckles easily than in people with dark skin.

The risk of melanoma is greatest for people who have a large number of atypical moles which is called dysplastic nevi. About one in 20 people has at least one unusual mole that looks different from an ordinary mole. The risk is especially high for people with a family history of both atypical moles and melanoma.

Ultraviolet radiation from the sun and from sunlamps and tanning booths damages the skin and can lead to melanoma and other types of skin cancer reducing exposure to ultraviolet (UV) radiation decreases the incidence of non melanoma skin cancer. Ultraviolet radiation is the high-energy rays coming from the sun. Artificial sources such as tanning booths and sunlamps also produce ultraviolet radiation.

Reducing exposure to the sun, wearing protective clothing such as a hat and long sleeves, and using adequate amounts of sunscreen can help lower your risk of skin cancer. Sunscreens are rated in strength according to a sun protection factor (SPF). The higher the SPF, the more sunburn protection is provided. Sunscreens with an SPF value of 2 to 11 provide minimal protection against sunburns. Sunscreens with an SPF of 12 to 29 provide moderate protection. Those with an SPF of 30 or higher provide high protection against sunburn. Sunglasses that have UV-absorbing lenses should also be worn. The label should specify that the lenses block at least 99% of UVA and UVB radiation. However, it is not known if avoiding sunburns reduces a person's chance of developing melanoma skin cancer.

A biopsy can usually be done using local anesthesia if the doctor suspects that a spot on the skin is melanoma. A pathologist then examines the tissue under a microscope to check for cancer cells. Sometimes it is helpful for more than one pathologist to check the tissue for cancer cells.