What causes moles and how can you monitor them?

What are moles?

Moles, also known as nevi, are pigmented formations on the skin resulting from the growth of pigment cells called melanocytes.

These skin melanocytes produce a pigment called melanin, which is responsible for the color of skin, hair, and eyes. Moles can vary in size, color, and shape, which can be round or oval, but they are generally brown or black spots that appear on the skin's surface.

 

What causes moles?

Most moles form during a person's lifetime, often as a result of exposure to the sun's ultraviolet (UV) rays. UV rays can stimulate melanin production, leading to the appearance of these small spots on the skin. However, it's important to note that some moles can also be present at birth and are genetically inherited.

Congenital moles, also known as congenital nevi, are present at birth or appear shortly after. They are not directly linked to UV exposure, as melanin, the pigment responsible for skin color, is already present in newborns.

Heredity plays an important role in the formation of congenital moles. If parents have moles, it's more likely that their child will also have them at birth. However, even if heredity can influence the presence of moles, other complex genetic factors also play a part in their development.

Generally, moles are considered benign skin formations and do not require specific treatment. However, it is crucial to monitor their evolution to detect any potential signs of skin cancers, particularly melanoma.

How to monitor moles and how to recognize a suspicious mole?

It is recommended to regularly monitor moles to detect any changes. If in doubt, it is essential to get screened and consult dermatologists. Vigilance is particularly important for atypical moles, characterized by irregular borders, uneven color, or unusual size.

The ABCDE method is often used to assess the potential danger of a mole:

• Asymmetry: Normal moles are usually symmetrical. Any asymmetry should be carefully examined.
• Borders: Regular borders are normal, but irregular borders can indicate a problem.
• Color: A uniform brown color is typical. Color variations can signal a problem.
• Diameter: Normal moles usually have a diameter less than 6 millimeters.
• Evolution: Any change in the size, shape, color, or texture of a mole should be reported.

 

Risk factors for the development of atypical moles

Atypical moles, also known as dysplastic nevi, are moles that have unusual characteristics compared to normal moles. Several risk factors can contribute to their development. 

• Family History: Individuals with a family history of melanoma or atypical moles have an increased risk of developing atypical moles. Genetic factors can play a role in the predisposition to these types of moles.
• UV Ray Exposure: While not all moles are directly linked to sun exposure, UV rays can contribute to the development of atypical moles. Excessive sun exposure, especially during childhood and adolescence, is a risk factor.
• Skin Type: Individuals with fair skin are generally more likely to develop atypical moles. People with fair skin and blond or red hair have less melanin to protect their skin from UV damage.
• Personal History of Sunburns: Repeated sunburns, especially during childhood, can increase the risk of developing atypical moles. Insufficient sun protection also contributes to this risk.
• Total Number of Moles: People with a large number of moles have a potentially higher risk of developing atypical moles. However, the sheer quantity of moles is not the only risk indicator.
• Hormonal Factors: Certain hormonal changes, such as those occurring during pregnancy, can influence the development of atypical moles.
• Age: Atypical moles tend to appear frequently during adolescence and one's twenties. However, they can develop at any age.

It is essential to note that even though these factors can increase the risk, their presence does not necessarily guarantee the development of atypical moles. Regular skin monitoring, recognizing signs of atypia, and consulting a dermatologist if in doubt are important practices for early detection and treatment of any potential issues.

 

Monitoring moles on the scalp

Moles can appear on all parts of the body, including the scalp. Due to the presence of hair, it can be more difficult to detect changes on the scalp. However, it is essential to regularly monitor this area, especially if sun exposure is frequent. Mirrors and hairdressers can help monitor moles on the scalp.

How to prevent the appearance of moles

While some factors related to mole formation, such as family history and genetics, are uncontrollable, there are preventive measures you can take to reduce the risk of new moles appearing and minimize the risks associated with these skin formations. Here are some tips to prevent the appearance of moles:

• Sun Protection: Exposure to the sun's ultraviolet (UV) rays is one of the main factors contributing to mole formation. Regularly use sunscreen with a high protection factor, even on cloudy days, and avoid excessive sun exposure.
• Avoid Sunburns: Frequent sunburns, especially during childhood, increase the risk of developing atypical moles. Protect yourself from the sun by wearing protective clothing and hats, and by seeking shade during the hottest hours of the day.
• Regular Monitoring: Regularly examine your skin to detect any changes in the size, color, shape, or texture of existing moles. Pay particular attention to atypical moles and consult a dermatologist if in doubt.
• Protective Clothing: Wear clothing that covers your skin, especially when it's hot and sunny. Opt for wide-brimmed hats, sunglasses, and long-sleeved clothing to minimize sun exposure.
• Avoid Tanning Beds: Tanning beds can also contribute to damage caused by UV rays. Avoid using tanning beds to reduce the risk of atypical moles forming.
• Balanced Diet: Certain nutrients, such as antioxidants found in fruits and vegetables, can contribute to skin health. Adopt a balanced diet to promote healthy skin.
• Stress Management: Chronic stress can affect skin health. Adopt stress management strategies, such as meditation, yoga, or other relaxing activities.
• Regular Dermatologist Consultations: Regular consultations with a dermatologist can help professionally monitor your skin. They can detect and evaluate atypical moles, provide personalized preventive advice, and recommend appropriate measures if needed.

It is important to note that even by taking these preventive measures, it is not possible to completely eliminate the risk of new moles forming. However, these tips can help minimize risks and maintain healthy skin. If you have any doubts or notice suspicious changes on your skin, always consult a healthcare professional.

What is melanoma?

Melanoma is a rare skin cancer, but it is the one with the fastest-growing number of new cases each year. It is also one of the leading causes of cancer in young people (patients are often between 25 and 35 years old).

Melanoma occurs when melanocytes (skin cells that produce melanin) multiply uncontrollably and become cancerous. The tumor most often remains localized in the epidermis.

If melanoma is not treated early, it can form metastases and spread to other organs. This may warrant chemotherapy treatment, but this is always determined by your doctor.

The risk of developing skin melanoma is higher if you do not consider the preventive measures we have mentioned.

Sources

• Heistein JB, Acharya U, Mukkamalla SKR. Malignant Melanoma. 2023 May 22. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2023 Jan–. PMID: 29262210.
• Davis LE, Shalin SC, Tackett AJ. Current state of melanoma diagnosis and treatment. Cancer Biol Ther. 2019;20(11):1366-1379. doi: 10.1080/15384047.2019.1640032. Epub 2019 Aug 1. PMID: 31366280; PMCID: PMC6804807.