Skin checks: who needs one, and the changes worth showing a dermatologist

Skin cancer 7 min readPublished October 11, 2026Reviewed October 11, 2026

Do you need a skin check?

In 2023, the U.S. Preventive Services Task Force (USPSTF) looked at whether doctors should routinely examine the skin of adolescents and adults who have no symptoms. It concluded that the evidence was insufficient to weigh the benefits against the harms. That's an "I" statement. It doesn't say screening is wrong. It says the studies we have can't answer the question for the general population.¹

The statement does not apply if you:

• have had skin cancer or a precancerous lesion before
• have a spot that is new, changing, itching or bleeding
• have a family syndrome or condition that puts you at high risk

The Task Force also lists risk factors worth discussing with a doctor: lots of UV exposure from the sun or tanning beds, frequent sunburns, older age, many or unusual moles, a family or personal history of skin cancer and, in white people, fair skin that burns easily, light eyes and red or blond hair.¹

The ABCDEs, and the ugly duckling

Most moles are harmless. These signs help pick out the one that deserves a closer look:²

• A, asymmetry. The two halves don't match.
• B, border. The edge is uneven, scalloped or notched.
• C, color. Several shades of brown, tan or black, or red, white or blue.
• D, diameter or dark. About 6 mm (the size of a pencil eraser) or larger, or darker than your other spots.
• E, evolving. Any change in size, shape, color or height, or new bleeding, itching or crusting.

The ugly duckling sign is just as useful. Your moles tend to look like one another. A mole that stands out from its neighbors, or a lone dark spot with no neighbors, is worth showing a dermatologist.²

Skin cancer in darker skin

Skin cancer is less common in people with brown and Black skin, but it is more often found late, when it's harder to treat. The Skin Cancer Foundation reports that 52% of non-Hispanic Black patients and 26% of Hispanic patients receive an advanced-stage melanoma diagnosis at first, compared with 16% of non-Hispanic white patients.³

In darker skin, skin cancer often appears where the sun rarely reaches. Check for:⁴

• a growing or changing dark spot on a palm or the sole of a foot
• a dark line or band along a nail, or darkening of the skin around a nail
• discolored areas on the lips, inside the mouth or in the genital area
• a sore that won't heal, or a rough patch that won't go away

Precancers count too

Actinic keratoses are rough, scaly patches on sun-damaged skin. They're often easier to feel than to see. Only about 5–10% turn into skin cancer, but most squamous cell carcinomas start as one, and treating them is straightforward.⁵

How to check your own skin

A monthly look takes about ten minutes. You need good light, a full-length mirror, a hand mirror and some privacy.⁴

1. Face, ears, lips and inside the mouth.
2. Scalp. Part your hair section by section, or ask someone to help.
3. Hands, including palms, nails and between the fingers.
4. Arms, underarms, chest and belly. Lift skin folds.
5. Back, buttocks and the backs of the legs, using the hand mirror.
6. Feet, including soles, nails and between the toes.

Photos help. Take a picture of any spot you're unsure about, in the same light, and compare it a month later.

Why early matters

When melanoma is found early, the five-year survival rate is 99%.³ Most other skin cancers are also simpler to treat, with smaller scars, when they're small.

This article is general education for adults and isn't a substitute for personal medical advice. In an emergency, call 911.