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Moles

(Melanocytic Nevi)

By

Denise M. Aaron

, MD, Dartmouth Geisel School of Medicine

Reviewed/Revised Sep 2023
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Moles are small, usually dark, skin growths that develop from pigment-producing cells in the skin (melanocytes).

  • Most people have some moles, but the tendency to develop atypical moles is sometimes hereditary.

  • Moles and atypical moles that change significantly should be biopsied for possible melanoma.

  • Most noncancerous (benign) moles do not require treatment, but moles that are uncomfortable or a cosmetic concern can be removed with a scalpel and local anesthetic.

Moles vary in size from small dots to more than 1 inch (about 2.5 centimeters) in diameter but are usually less than 1 centimeter and tend to be less than 6 millimeters (about ¼ inch). Almost everyone has a few moles, and many people have large numbers of them. People who have more than 50 moles have a somewhat increased risk of melanoma Melanoma Melanoma is a skin cancer that begins in the pigment-producing cells of the skin (melanocytes). Melanomas can begin on normal skin or in existing moles. They may be irregular, flat or raised... read more Melanoma , a cancerous (malignant) growth of melanocytes. They should self-monitor for changes in their moles (see the ABCDEs of melanoma Diagnosis Moles are small, usually dark, skin growths that develop from pigment-producing cells in the skin (melanocytes). Most people have some moles, but the tendency to develop atypical moles is sometimes... read more Diagnosis ) and also have them examined periodically as part of their primary care.

Moles may be flat or raised, smooth or rough (wartlike), and may have hairs growing from them. Moles are typically skin-colored, yellow, brown, blue-gray, or nearly black. They may be red at first but often darken.

Moles

Moles commonly develop in childhood or adolescence, and existing moles often enlarge (in proportion to the body's growth) and may darken. In some people, moles continue to develop throughout life. Moles can appear anywhere on the body. Moles respond to changes in hormone levels in women and may darken during pregnancy. Once formed, moles remain for a lifetime and get less pigmented and more raised or fleshy with time. In fair-skinned people, moles occur more commonly on sun-exposed areas of the skin.

Did You Know...

  • Moles may darken during pregnancy.

Diagnosis of Moles

  • Examination of the skin

  • ABCDEs of melanoma

  • Sometimes biopsy

Moles usually are easily recognized by their typical appearance. They are symmetric and round or oval and have regular borders. They do not itch or hurt, and they are not a form of cancer. However, moles sometimes develop into or resemble melanoma Melanoma Melanoma is a skin cancer that begins in the pigment-producing cells of the skin (melanocytes). Melanomas can begin on normal skin or in existing moles. They may be irregular, flat or raised... read more Melanoma . In fact, many melanomas begin in moles, so a mole that looks suspect should be removed and examined under a microscope (biopsy Biopsy Doctors can identify many skin disorders simply by looking at the skin. A full skin examination includes examination of the scalp, nails, and mucous membranes. Sometimes the doctor uses a hand-held... read more Biopsy ).

The following changes in a mole may be warning signs of melanoma (known as the ABCDEs of melanoma):

  • A: Asymmetry—asymmetric appearance (that is, one half does not look the same as the other half)

  • B: Borders—irregular borders (that is, borders are blurred or jagged, not well-defined and smooth)

  • C: Color—color changes within the mole, unusual colors, or a color significantly different or darker than the person's other moles

  • D: Diameter—more than ¼ inch (about 6 millimeters) wide, about the size of most pencil erasers

  • E: Evolution—a new mole in a person over age 30 or a changing mole

If a mole becomes painful, itchy, bleeds, develops broken skin, or has any warning signs of melanoma, doctors may do a biopsy. If a mole proves to be cancerous, additional surgery may be needed to remove the skin surrounding it.

Treatment of Moles

  • Sometimes removal

Most moles are harmless and do not require removal. Depending on their appearance and location, some moles may even be considered beauty marks.

Normal moles that are unattractive or located where clothing can irritate them can be removed by a doctor using a scalpel and a local anesthetic.

Atypical moles

People who have atypical moles have an increased risk of developing melanoma Melanoma Melanoma is a skin cancer that begins in the pigment-producing cells of the skin (melanocytes). Melanomas can begin on normal skin or in existing moles. They may be irregular, flat or raised... read more Melanoma , which is cancer of the pigment-producing cells in the skin called melanocytes. The risk of developing melanoma increases when the number of moles increases. Risk also increases in people who spend a lot of time in the sun.

The tendency to grow atypical moles can be hereditary, as in familial atypical multiple mole–melanoma syndrome. In this disorder, many atypical moles and melanoma occur in 2 or more first-degree relatives (such as a parent, sibling, or child), and family members have a greater risk of developing melanoma.

Symptoms of Atypical Moles

Atypical moles tend to be multicolored, usually in tones of brown and tan against a lighter background; asymmetric; and to have irregular shapes and borders. They are often larger than (more than ¼ inch [about 6 millimeters] wide) most normal moles. Atypical moles most commonly appear on sun-exposed skin but may occur on covered areas (such as the buttocks, breasts, or scalp).

Diagnosis of Atypical Moles

  • Physical examination

  • Biopsy

People who have a family history of melanoma should have their skin checked by a dermatologist (a doctor who specializes in skin disorders) and learn about signs of melanoma. People who have had a melanoma should have their skin checked regularly by a dermatologist.

Some dermatologists closely inspect the skin using a hand-held instrument (a procedure called dermoscopy) to see structures in the mole that are not visible to the naked eye and that may indicate that melanoma is more or less likely.

Prevention of Atypical Moles

  • Self-examination

  • Photographs of moles

  • Sun protection

People with atypical moles must regularly look for new moles and any changes Diagnosis Moles are small, usually dark, skin growths that develop from pigment-producing cells in the skin (melanocytes). Most people have some moles, but the tendency to develop atypical moles is sometimes... read more Diagnosis in existing moles that might indicate melanoma. To help monitor such changes, they and their dermatologist may take full-body color photographs over time. Atypical moles that change may sometimes be removed.

Skin damage caused by ultraviolet (UV) radiation from the sun is a cause of melanoma, particularly recreational sun exposure and sunburns. To limit damage caused by UV radiation, people should avoid the sun Avoidance Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more Avoidance during peak hours (about 10 AM to 4 PM) when possible, wear sun-protective clothing Clothing Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more Clothing , and use and frequently reapply a broad-spectrum sunscreen Sunscreens Sunburn results from a brief (acute) overexposure to ultraviolet (UV) light. Overexposure to ultraviolet light causes sunburn. Sunburn causes painful reddened skin and sometimes blisters, fever... read more Sunscreens (such as one that contains zinc oxide or titanium dioxide). People who greatly limit their exposure to the sun may need to take supplemental vitamin D, particularly as they age.

Treatment of Atypical Moles

  • Sometimes removal

People who have an atypical mole or a mole that is new or changing should be evaluated by a dermatologist, who will determine whether the mole should be removed. Removing all atypical moles does not prevent melanoma.

More Information

The following English-language resource may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

  • The Skin Cancer Foundation: This organization empowers people to proactively practice sun protection, early detection, and early treatment of skin cancer by providing everything from a list of recommended sun protection products to guidance on finding a dermatologist.

Drugs Mentioned In This Article

Generic Name Select Brand Names
Aquaphor 3 IN 1 Diaper Rash, Aquaphor Baby Fast Relief Diaper Rash, Aquaphor Fast Relief Diaper Rash, Balmex, Boudreaux Butt Paste, Boudreauxs Rask, Carlesta, Coppertone, COZIMA, Critic-Aid Thick Moisture Barrier Skin, DermacinRx Zinctral, Desitin, Desitin Maximum Strength, Desitin Rapid Relief, Diaper Rash , Dr. Smith Adult Barrier, Dr. Smith's, Dr. Smith's Diaper Rash, Dr. Smith's Rash + Skin, DynaShield, Eucerin Baby Sunscreen Sensitive Mineral , Eucerin Sunscreen Sensitive Mineral, Flanders Buttocks , Medi-Paste, Novana Protect, PanOxyl AM, SECURA, Triple Paste, Triple Paste Adult Incontinence, Triple Paste Rash, Z-Bum
Calcidol, Calciferol, D3 2000, D3 5000, D3 Vitamin, DECARA, Deltalin, Dialyvite Vitamin D, Dialyvite Vitamin D3, Drisdol, D-Vita, Enfamil D-Vi-Sol, Ergo D, Fiber with Vitamin D3 Gummies Gluten-Free, Happy Sunshine Vitamin D3, MAXIMUM D3, PureMark Naturals Vitamin D, Replesta, Replesta Children's, Super Happy SUNSHINE Vitamin D3, Thera-D 2000, Thera-D 4000, Thera-D Rapid Repletion, THERA-D SPORT, UpSpring Baby Vitamin D, UpSpring Baby Vitamin D3, YumVs, YumVs Kids ZERO, YumVs ZERO
NOTE: This is the Consumer Version. DOCTORS: VIEW PROFESSIONAL VERSION
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