First the not-so-good news, skin cancer is the most common of all cancers. More than three million Americans turn up with nonmelanoma skin cancer each year, and new melanoma cases number more than 100,000. Now the good news: Prevention is your best friend, and most skin cancers, if detected and treated early, can be cured.

Carcinoma vs. Melanoma

Don’t panic if your doctor finds basal cell carcinoma (BCC) on your skin; it’s the most common skin cancer and the least dangerous. BCC is an abnormal growth in the skin’s basal cells, which line the deepest layer of the epidermis (the outermost skin layer). Fortunately, BCC almost never spreads to other parts of the body.

More serious squamous cell carcinoma (SCC) is an abnormal, uncontrolled growth in the squamous cells, which make up most of the skin’s upper layers. SCC can be disfiguring and, in rare cases, deadly if untreated. Your doctor can remove both BCC and SCC growths.

Melanoma, the most dangerous form of skin cancer, occurs when DNA damage to the skin triggers mutations and causes cells to multiply rapidly and form malignant tumors. That’s why paying attention to your skin matters: If caught early, melanoma can be treated with removal and chemotherapy, but if left untreated it can spread and become fatal.

Who's at Risk

Your skin cancer risk increases if you have:

• Too much exposure to ultraviolet (UV) light from sunlight or tanning beds. UV rays cause most skin cancers, so protect yourself in the sun and forget about tanning beds.
• A personal or family history of skin cancer.
• Fair skin that burns easily (typically people with blonde or red hair).
• A weakened immune system.
• Many moles. Most moles are harmless, but if you have dozens of moles that vary in size and color, you may have a higher risk of melanoma.

Do a Self-Check

Early detection is key. As part of your regular checkups, make sure your doctor looks at your skin carefully. Between checkups, perform a monthly skin self-check. That way you’ll know what’s normal and what may have changed:

• In a well-lit room and in front of a full-length mirror, look at your skin carefully.
• Use a hand mirror or ask a partner to examine any hard-to-see areas, like your back.
• Although most skin cancers develop in high-sun-exposure areas (shoulders and face), also examine your palms, fingernails and feet.
• Note any changes in your moles’ size, shape or color and any new growths, spots, bumps, patches or sores that don’t heal after two to three months.

Easy as ABCDE

You can learn the difference between harmless and abnormal moles. A normal mole is usually an evenly colored brown, tan or black spot that’s less than a quarter inch across (about the width of a pencil eraser). It can be flat or raised, round or oval. Once developed, most moles remain consistent over time.

Use “ABCDE” to identify abnormal spots:

A = Asymmetry. One half of a mole does not match the other half

B = Border irregularity. The edges are not smooth and look ragged, blurred or notched.

C = Color. The color is not the same all over and you may see shades of tan, brown or black, or patches of pink, red, white or blue.

D = Diameter. The spot is larger than about a quarter inch.

E = Evolving. The mole changes in size, shape, color or elevation, starts to feel tender or painful, or begins to bleed, itch or crust.

Also watch out for:

• Pigment that spreads from a spot’s border to surrounding skin.
• Redness or a new swelling beyond the border.
• Appearance of a bump or nodule on the surface.
• A mole that looks very different from your other moles.
• Actinic keratosis, a sometimes precancerous skin condition. These pink-red or flesh-colored rough spots of less than a quarter inch usually appear on the face, ears, hands and arms of middle-aged or older people with fair skin. These spots may also develop on younger people and on other areas of sun-exposed skin.

If anything concerns you during a self-exam, make an appointment to discuss it with your doctor right away.