Mole vs Melanoma: Knowing the Difference Could Save Lives

The common mole and melanoma are lesions derived from melanocytes, the skin’s pigment-producing cells. The first condition is harmless, while the second is one of the most treacherous cancer types known to science. Most people will develop a few common moles in their lifetimes, but there are those who are particularly susceptible to melanoma development.

Early melanoma detection matters because timely treatment saves lives. And when looking for this malignancy, it helps to know what it may look like and which individuals are vulnerable.

This article provides a quick guide for distinguishing common moles from melanomas. It also discusses the risk factors for melanoma skin cancer formation and the treatments BHSkin Dermatology specialists use to get rid of these growths. 

How Can You Tell the Difference Between a Mole and Melanoma?

Before we get into that discussion, you must know that non-medical people use the word “mole” for various dark or raised skin lesions regardless of which cell types are involved. There are many skin cell types, each performing a different function. Common moles and melanomas result from the over-proliferation of the skin’s pigment-producing cells, the melanocytes.

Common moles, also known as common or typical acquired nevomelanocytic nevi, are made up of normal melanocytes. By comparison, melanomas arise from malignant melanocytes. The discussion below centers around these two dermatologic conditions. As you will see, they differ not only by their physical appearance but also by their clinical history.

The ABCDE Melanoma Recognition Guide

Common moles appear after birth. Some develop in the first 6-12 months of life, but most spring up during adolescence or early adulthood. They are round or oval, typically only a few millimeters in size. Their edges are smooth and can be easily distinguished from the surrounding skin.

These lesions have homogeneous pigmentation. Flat moles are usually brown or brown-black, involving only the superficial layers of the skin. Raised moles, which grow deeper, are flesh or pink-colored. Some of these lesions have hair coarser, longer and darker than that of the surrounding area. Others attach to the skin surface by a stalk. 

Common moles can stay unchanged for many years. If they enlarge, they do so gradually, retaining their shape, symmetry and color. They can also disappear later in life. These pigmented lesions do not normally pose serious health risks.

In contrast, most melanomas appear in middle to late adulthood, with only 1-4% of new cases diagnosed before age 20. These cancerous lesions have irregular shapes and tend to grow larger than six millimeters. Crooked edges and abnormal pigmentation are common. Colors considered suspicious for a mole are blue, gray, red, and white, and they may all be present in the same melanomatous growth.

Other symptoms may accompany these changes, notably itchiness, tenderness, ulceration and bleeding with the slightest trauma. Advanced melanoma can invade any organ, so it manifests in myriad ways.

Pigmented cancer cells multiply faster than normal melanocytes. Lesions can enlarge and change shape and color in a few months.

The ABCDE melanoma recognition guide can help you distinguish a normal from an abnormal mole.

One subtype, nodular melanoma, may look like a dome-shaped common mole at first because of its symmetry and even pigmentation. But its ominous color (red, blue or white), bumpy margins and rapid growth eventually reveal its malignant nature.

Which Individuals Are at Risk for Melanoma Formation?

Doctors suspect melanoma when a patient with an atypical mole has the following risk factors in their medical history or physical examination:

Excessive UV Radiation Exposure

Too much sun can cause sunburns, manifesting as skin reddening or blistering that may last for more than 12 hours. A history of sunburn in childhood more than doubles one’s odds of developing melanoma during adulthood. Sunburns in older individuals also increase their melanoma risk. 

The use of PUVA and UVB phototherapy and tanning booths can also increase melanoma susceptibility, especially when the radiation is given at high doses.

Fair Skin 

Individuals with Fitzpatrick I and II skin phototypes have a greater risk of developing melanoma than those with Fitzpatrick III-VI complexion. These people have fair skin, red or blonde hair and blue or green eyes. They are also more likely to have had freckles or sunburns in the past.

Having Multiple Moles

This pigmented skin cancer is more frequently seen among the following:

• Adults with more than 100 common moles
• Children with more than 50 typical moles
• Patients with any number of atypical moles

Only 25-30% of melanomas evolve from common moles. The rest arise from normal-looking skin. Moles are not necessarily premalignant, but a steep rise in number and the appearance of atypical features are associated with skin cancer.

Having a Large Congenital Mole

Unlike the common mole, a congenital mole is inborn.

Large ones, i. e. those having greater than 20 centimeters in diameter, are potentially premalignant. Many cases become cancerous before age 10. Early diagnosis is not always possible as malignant transformation often starts deep within the lesion.

Meanwhile, smaller congenital moles have a reduced melanoma risk. They may become malignant later in life, and when they do, the change is easier to detect, occurring in the superficial parts of the mole. 

Dermatologists may recommend the prophylactic removal of a congenital mole depending on its size and other clinical features.

Personal History of Melanoma or Any Prior Cancer Treatment

Melanoma is an aggressive skin cancer with an unpredictable clinical course. Total cure is possible with early diagnosis and appropriate treatment. But recurrences even decades after the initial diagnosis are not unheard of. So a prior history of melanoma markedly increases one’s risk of developing another lesion later in life.

Radiotherapy and chemotherapy for other cancer types can also induce malignant melanocyte transformation, thus raising melanoma vulnerability. 

Family History of Melanoma or Other Skin Cancer Types

Some forms of melanoma are hereditary, occurring in families. These syndromes usually have an earlier age of onset, with lesions growing in multiples.

Non-familial types also confer some melanoma risk to members of the same family. Having one first-degree relative with melanoma doubles the odds of another family member developing the same condition. Having more than three increases the risk up to 70 times. A family history of non-melanoma skin cancer also raises melanoma predilection.

Acquired or Inborn Genetic Mutations

Some DNA mutations can predispose people to skin cancer formation. The mutations may be inborn or induced by an environmental trigger, such as cigarette smoking. Affected individuals grow melanomas even with little or no UV exposure.

Immunosuppression

The immune system protects us from various diseases, including skin cancer. So the immunocompromised are generally tumor-prone. Examples are people on chronic steroid therapy, such as organ transplant recipients and lupus patients.

Consult your dermatologist immediately when you find a suspicious skin lesion, especially if you have any of the above risk factors.

What Happens if You Do Not Treat Melanoma Right Away?

Melanoma is rarer than basal cell carcinoma and squamous cell carcinoma of the skin, but it is more aggressive. Without treatment, it can spread to the lymph nodes, nerves and other organs in less than a year.

Invasion of the nervous system can cause paralysis and other stroke-like symptoms. Metastasis to the heart, bones, lungs and other organs can likewise compromise their function. A patient’s survival depends on the severity of malignant spread to these organs.

Melanoma may not respond if treated at an advanced stage. Therapeutic delay drastically reduces the odds of success. Even if it disappears, it may recur within months or decades after therapy, making long-term post-treatment surveillance necessary.

According to the Centers for Disease Control, the death rate of melanoma in the US is 2.5 per 100,000 population. One American dies from this disease every hour. Despite its relative rareness, four out of five of all skin cancer deaths are due to melanoma.

How Can You Prevent Mole and Melanoma Growth?

Sun protection is essential for preventing both conditions, and it needs to start as early as childhood. You can do the following for yourself and your loved ones:

• Wear sunscreen outdoors, with SPF 30 or higher.
• Minimize exposure to the midday sun.
• Schedule your daytime outdoor activities early in the morning and late in the afternoon.
• Seek shade or wear wide-brimmed hats in the daytime.

Additional melanoma preventive measures include the following:

• Carcinogen avoidance

A healthy lifestyle can help you avoid various cancer-causing substances. Eat healthily and hydrate adequately. Don’t smoke. Drink alcohol sparingly. Detox, meditate and exercise regularly. Use only dermatologist-recommended skincare products.

• Periodic skin self-checks

Periodic self-checks help detect this cancerous mole early, preventing distant spread. Melanoma can affect any skin type, not just fair skin, so everyone must perform a skin self-exam regularly as part of health maintenance.

Inspect all visible surfaces of your upper and lower limbs. Use a full-length mirror to examine your bare trunk and back. Check your face, ears, neck, scalp and groin area using a hand mirror. Look for new lesions or changes in an old skin growth, keeping in mind the ABCDE guide.

Monthly self-checks are recommended for high-risk individuals, e. g. fair-skinned older adults, patients with more than 100 moles and those with a personal or family history of skin cancer. Low-risk people may perform skin self-exams yearly.

• Dermatology visits as needed

Your dermatologist is the best person to teach you how to differentiate a typical mole or skin tag from a melanoma. They can also guide you on how to perform self-skin checks properly and what to do when you spot a suspicious lesion. 

High-risk patients may be advised to visit their dermatologist once every month. This helps them validate their self-check findings and document the appearance of a new mole or changes in an existing one. Low-risk individuals may consult their dermatologist at least once a year to ensure skin health.

An ounce of prevention is worth much more than a pound of cure for aggressive malignancies like melanoma. But once it occurs, vigilance is key to avoiding severe illness.

What Can You Expect During Your Dermatology Consultation for a Pigmented Skin Lesion?

At BHSkin Dermatology, our doctors treat every patient with utmost care.

Most skin problems can be recognized on the spot, but they will want to hear more about how your lesion evolved and if you noticed other symptoms. They will note your past illnesses, family history and lifestyle to help with diagnosis and treatment planning.

After taking your medical history, they will inspect the lesion more closely. For moles, they may use a dermatoscope to look for melanoma features. They may ask to photograph the problem area for documentation and, possibly, post-treatment comparison later. If they suspect skin cancer, they may ask permission to check other parts of your body for distant spread. Your dermatologist will ensure your privacy throughout the examination.

At the end of your visit, your dermatologist will discuss the likely diagnosis. Depending on their findings, they may suggest to keep monitoring the lesion or schedule you for a biopsy and possible treatment. 

How Do BHSkin Dermatology Specialists Treat Moles and Melanomas?

Benign moles do not need treatment unless they are inflamed, though some patients want them removed for cosmetic reasons

For solitary raised moles, your doctor at BHSkin Dermatology may recommend surgical excision as it allows further tissue examination for skin cancer cells. For multiple benign lesions, they can perform other procedures like electrosurgery, cryotherapy, dermabrasion and laser therapy. Insurance does not cover cosmetic treatments, so you must work with your doctor to determine your best option.

On the other hand, melanoma treatment is not as straightforward. After making the diagnosis, you may need a full workup for malignant spread.

Wide tumor excision is the treatment of choice if it is operable. This technique entails taking out the entire lesion together with a considerable portion of the surrounding normal skin.

However, your BHSkin Dermatology specialist may recommend Mohs micrographic surgery if it is suitable for you. In this technique, the doctor cuts out thin layers of the tumor at a time until they obtain a small, cancer-free margin. This tissue-sparing procedure renders high cure rates and the best cosmetic results, but it is appropriate only for early-stage melanoma. Only specially trained dermatologists can perform Mohs surgery.

Radiotherapy, chemotherapy and biologics may be given as adjunct treatment for metastatic lesions or to alleviate symptoms in treatment-resistant cases.

Recap: The Difference Between a Mole and Skin Cancer

Common moles are generally small, round to oval skin growths with smooth borders and uniform color. Melanomas can grow bigger than a pencil eraser, and they have an irregular shape and heterogeneous color. You can tell them apart more easily using the ABCDE guide.

Healthy moles need no treatment but may be removed by various cosmetic procedures if a patient so chooses. Meanwhile, operable melanomas may be taken out by wide excision or Mohs surgery. Metastatic disease may be treated with radiotherapy, chemotherapy and biologics. However, melanoma is an aggressive type of cancer, and advanced cases are often resistant to therapy.

The ability to distinguish a normal mole from melanoma can help save lives. Consult with a board-certified dermatologist immediately if you have a concerning skin lesion.

Not Sure if You Have a Mole or Melanoma? Ask the Experts at BHSkin Dermatology

Melanoma is the most dangerous skin cancer type, but it can resemble a sun spot or benign mole in its early stages. Prevention is the best way to avoid serious illness. But once it appears, early recognition and treatment give patients the best chance of returning to normal life.

At BHSkin Dermatology, our specialists offer various procedures to remove pigmented lesions, restore your flawless complexion and put you at ease about your skin’s health. Visit us at our Glendale or Encino clinic or use our virtual portal for your initial consultation.

Book your appointment today!

Author: Don Mehrabi

Don Mehrabi, MD, FAAD, is LA’s leading board-certified dermatologist who treats patients, builds the BHSkin clinics, and raises three kids. This blog builds on medical studies combined with Dr. Mehrabi's first-hand experiences from practicing in Encino-Tarzana, Glendale, and online