Moles – Symptoms and Causes

Overview

Moles, or nevi, are common skin growths. They typically appear as small brown spots caused by groups of melanocytes (pigment-forming cells). Most people develop between 10 and 45 moles during childhood and adolescence.

These skin marks may change in appearance or gradually fade as a person ages.

While the vast majority of moles are benign, in rare cases they can become cancerous. Monitoring changes in moles and other pigmented skin areas is crucial for early detection of skin cancer, particularly malignant melanoma.

Signs to Watch For

Strange Moles That Might Be Melanoma

Moles come in various forms. Most are small brown spots, but they can appear in different colors like tan, black, blue, red, or pink. They may feel smooth or wrinkled and can be flat or raised. Some even have hair growing from them.

Typical moles are round or oval, usually smaller than a pencil eraser (about 6 mm). They can appear anywhere on your body—including your scalp, armpits, under nails, and between fingers and toes.

Most people have between 10 and 45 moles, with many developing by age 40. These spots may change or fade over time, especially during hormonal changes like puberty or pregnancy.

To identify potentially dangerous moles, remember the ABCDE rule:

• A – Asymmetry: One half looks different from the other.
• B – Border: Irregular, notched, or scalloped edges.
• C – Color: Multiple colors or uneven coloring.
• D – Diameter: Larger than 1/4 inch (6 mm).
• E – Evolution: Changes in size, shape, color, or height; new symptoms like bleeding or itching.

Dangerous moles vary greatly in appearance. Some might show all these warning signs, while others display only one or two unusual features.

Black people, especially women, may have clusters of brown spots around the eyes, cheeks, and nose called dermatoses papulosa nigra. These are harmless growths that don’t increase melanoma risk but can be treated for cosmetic reasons if desired.

When To Consult a Doctor

Make a doctor’s appointment if you notice any mole that:

1. Looks unusual or different from your other moles
2. Is growing larger
3. Changes color, shape, or texture
4. Begins to itch, bleed, or cause discomfort
5. Matches any of the ABCDE warning signs

Get your moles checked promptly, especially if you have a family history of skin cancer or spend a lot of time in the sun.

Regular skin self-examinations can help you spot changes early. Consider taking photos of concerning moles to track any changes over time before your appointment.

Causes

Moles form when skin cells known as melanocytes gather in groups rather than spread out. These melanocytes are normally found throughout the skin layers. Their main job is to create melanin, the natural substance that gives skin its color.

Complications

Melanoma is the primary concern with moles. Some individuals face higher risks of their moles becoming cancerous. Several factors increase this risk:

Risk Factors for Melanoma:

• Large Birth Moles: Known as congenital nevi, these are classified by their adult size. Large and giant ones (over 20 centimeters) carry a higher cancer risk.

• Unusual Moles: Atypical nevi (dysplastic nevi) have irregular borders and are often larger than normal moles. These tend to run in families.

• High Mole Count: Having more than 50 moles suggests an increased risk for melanoma and possibly breast cancer.

• Previous Melanoma – Those who have had melanoma face a higher risk of developing it again.

• Family History – Some atypical moles are linked to genetic forms of melanoma.

• Artificial Tanning – Using tanning beds or lamps increases skin cancer risk due to UV ray exposure.

Ways to Prevent Skin Problems

Monitor Skin Changes

Get to know where your moles are located and how they look. Do a full skin check once a month using mirrors to examine your entire body, including:

• Top of your head
• Hands and under fingernails
• Underarm areas
• Torso
• Lower limbs
• Feet (bottoms and between toes)
• Private areas

Protect Your skin

Take steps to shield your skin from harmful ultraviolet (UV) light. This includes UV light from sunlight or artificial tanning sources. UV exposure has been connected to a higher melanoma risk.

Children who aren’t protected from the sun tend to develop more moles.

Avoid peak sun hours. In North America, UV rays are strongest between 10 a.m. and 2 p.m. Plan outdoor activities outside these times, even on cloudy or winter days. Seek shade or use umbrellas when outdoors.

Use sunscreen consistently:

• Apply to dry skin 15 minutes before going outside
• Choose broad-spectrum, water-resistant products with SPF 30+
• Apply generously
• Reapply every two hours or after swimming or sweating

Wear protective items:

1. Sunglasses
2. Wide-brimmed hats
3. Long-sleeved shirts
4. Other protective clothing

Consider specially treated fabrics designed to block UV radiation for better protection.

Avoid tanning beds and lamps. These devices emit harmful UV rays that can significantly increase your skin cancer risk.