Skin Cancer

Skin cancer is the most common form of cancer in the United States. More than 90% of skin cancers are caused by sun exposure. Skin cancers are divided into two major groups: nonmelanoma and melanoma.

Nonmelanoma skin cancers (usually basal and squamous cell) are the most common skin cancers. They develop from all types of skin cells except melanocytes.

Melanoma is almost always curable in its early stages but is likely to spread to other parts of the body when left untreated. Melanoma is much less common than basal cell and squamous cell skin cancers, but it is much more serious.

Facts: In the past decade (2014-2024), the number of new invasive melanoma cases diagnosed annually increased 32%. From 2016 to 2020, national trends in mortality declined by 2.5% each year.

According to the Illinois State Cancer Registry, in 2021, there was 3,731 new cases of melanoma diagnosed in Illinois. In 2021, there were 270 deaths due to melanoma in Illinois. From 2016 to 2020, Illinois trends in mortality declined by 5.2% each year.

Most basal cell and squamous cell skin cancers are caused by ultraviolet (UV) radiation produced by the sun, but other risk factors are also linked to these cancers. The factors listed below can increase the risk for skin cancer.

Too much exposure to UV radiation. The main source of such radiation is sunlight and tanning lamps and booths.

People with fair skin, freckling, or red or blond hair have a higher risk. The risk of skin cancer is much higher for Whites than for dark-skinned African Americans.

Certain types of moles, including some large moles, increase the chance of getting melanoma.

People with a family history of skin cancer are at increased risk. A person who has already had melanoma is at a higher risk of getting another melanoma.

Exposure to large amounts of arsenic, a heavy metal used in making some insecticides, increases the risk of nonmelanoma skin cancer.

Radiation treatment increases the risk of developing nonmelanoma skin cancer in the area that was treated.

Men are more likely to develop skin cancer than women.

More than 50% of all melanomas occur in people older than 50 years of age.

Skin cancers often do not cause symptoms until they become quite large, at which point they can bleed or even hurt. Melanoma can occur anywhere on the body. It is important to know the difference between melanoma and a harmless mole.

The ABCD rule can help determine whether a mole is normal or a melanoma. If a mole has the following characteristics, it might be a melanoma:

1. asymmetry – one half of the mole does not match the other half.
2. border irregularity – the edges of the mole are ragged or notched.
3. color – the mole's color is not the same all over. There may be shades of tan, brown, or black, and sometimes red, blue, or white patches.
4. diameter – the mole is wider than about one-fourth an inch.

• Nonmelanoma skin cancers are found on areas of skin exposed to the sun.
• Basal cell carcinomas often appear as flat, firm, pale areas, or small, raised, pink or red, translucent, shiny, waxy areas that may bleed after minor injury. Large ones may have oozing or crusted spots.
• Squamous cell cancer may appear as growing lumps, often with a rough surface or as flat, reddish patches that grow slowly.

It is important to report any of these symptoms to a doctor.

• The best way to lower the risk of skin cancer is to avoid excessive exposure to the sun and other sources of UV radiation. Avoid being outdoors in sunlight for long periods, especially in the middle of the day when UV radiation is most intense.
• Protect your skin with clothing, including a long-sleeved shirt and a hat with a broad brim.
• Use sunscreen and lip balm with an SPF factor of at least 15. Apply sunscreen about 20 to 30 minutes before you go outside so your skin can absorb it and reapply every two hours.
• Wear sunglasses or goggles (wrap-around sunglasses with at least 99% UV absorption provide the best protection).
• Avoid other UV light sources, such as tanning beds and sun lamps.
• Teach your children to protect themselves from the sun. People who suffer severe blistering sunburns, particularly in childhood or teenage years, are at increased risk of melanoma.

• American Cancer Society
• National Cancer Institute
• American Academy of Dermatology