Causes

What causes melanoma?

Simply put . . . sun exposure and genetic susceptibility (heredity). The interplay of risk factors (listed in the next section), DNA damage from sunlight, and the inheritance of genes that predispose one to melanoma are interlinked in causation.

Another rare but possible route to contract melanoma is through organ transplantation. Researchers in the February 2003 issue of the New England Journal of Medicine stated that two patients got cancer from a donor who had undergone surgery for a melanoma lesion 16 years earlier and was thought to be cancer-free (MacKie et al, 2003). Since melanoma cells can lie dormant for many years within the body, people with melanoma should not donate organs.

How does melanoma get started?

Melanoma arises from melanocytes. These are the same skin cells that cause darkening (tanning) in reaction to sun exposure. Melanocytes are there to give us some protection from the damaging effects of ultraviolet (UV) radiation. The same type of UV radiation (sunlight) that these melanocytes protect us from can cause them to mutate and become a cancer (an abnormal growth of cells that lacks the usual controls to keep cells from dividing indiscriminately).

The World Health Organization estimates that UV radiation is responsible for 2-3 million skin cancers worldwide each year, including 132,000 malignant melanomas (UPI, 2002). According to the American Academy of Dermatology, 1 in 68 Americans risks developing melanoma in their lifetimes, a 2000% increase from 1930.

Persons with melanoma have a genetic predisposition to this cancer. Persons with basal cell skin cancer may also have a genetic predisposition to further basal cell cancers and melanoma.

"Even a single blistering sunburn in adolescence would double the risk of developing malignant melanoma later in life."

Arthur Sober, MD, Dermatologist and Melanoma Expert, Massachusetts Gen. Hospital, Safe in the Sun by Mary Ellen Siegel

"Only one third of 10,000 youths between ages 12-18 routinely use sunscreen in summer; more than 80% sunburn in summer"

Sun & Skin News, 2002, The Skin Cancer Foundation

"By age 15, about 16% of girls use tanning beds; by age 17, the percentage doubles."

Sun & Skin News, 2002, The Skin Cancer Foundation

"Once considered a disease of middle age and later, skin cancer is on the rise in young people, dermatologists say. About 1 in 4 people with melanoma is now younger than 40, and the rate is growing particularly fast in young women."

Contra Costa Times - July 23, 2002