Is It a Mole or Skin Cancer? How To Tell the Difference

New, unusual, or changing moles can be early signs of melanoma and other types of skin cancer. It's important to know how to tell when a mole is healthy and when it's cancerous to help you get treatment sooner.

Skin cancer is the most common form of cancer in the U.S. It occurs when cells in your skin grow out of control and is often caused by exposure to ultraviolet (UV) light. Besides unusual moles, other skin changes that can indicate skin cancer include blemishes, bumps, lumps, markings, sores, or differences in how the skin looks or feels. You are more at risk for skin cancer if you have a family history of the disease, as well as if you have light-colored skin, blue or green eyes, blonde or red hair, or skin that burns, freckles, or reddens easily.

The best way to find skin cancer early is to be aware of the warning signs and check your skin and moles often. If skin cancer is found early, treatments are available. Read on to learn how to tell when a mole might be cancer.

How To Check Your Moles for Skin Cancer

Checking your skin is a crucial step to preventing skin cancer. A dermatologist can check your skin, but you can also watch for anything suspicious. The "ABCDE" rule—asymmetry, border, color, diameter, and evolving—can be a great tool to monitor your moles. You should talk to your healthcare provider or dermatologist if any of your moles appear to be:

• Asymmetrical
• Irregular or blurred on its borders' edges
• Varying shades of color
• Larger than 1/4 inch across in diameter
• Changing in color, size, or shape

To find out whether it is a healthy mole or cancer, check your skin every few months. Most skin cancers start as irregular spots, said Ariel Ostad, MD, assistant professor of dermatology at New York University.

Normal Mole

What it is: A mole, or a nevus, is a harmless spot that occurs when pigment cells, or melanocytes, grow in clusters. Most moles develop in childhood, and people may continue growing moles until they're around 40 years old. Moles can be anywhere on your body.

Looks like: Typically smaller than a pencil eraser, moles are round and symmetrical with smooth borders and an even color of brown, pink, or tan. According to Dr. Ostad, "They usually don't evolve or change shape."

Is it cancerous? Common moles are usually not cancerous, but in rare cases, they can turn into skin cancer.

Actinic Keratosis

What it is: Actinic keratosis is a common precancerous growth often found on your face, lips, ears, scalp, shoulders, neck, and back of the hands and forearms. In other words, they commonly appear on parts of your body that are often exposed to the sun, especially in older adults who have had decades of sun exposure.

Looks like: You'll see a rough, dry, scaly, or crusty patch that is flesh-toned pink, red, tan, or white. Actinic keratosis may be mistaken for an age spot, pimple, or patch of irritated skin.

Treatment: Though they can be benign, actinic keratosis can progress to squamous cell carcinoma, a type of skin cancer. You should see a healthcare provider if you suspect you have actinic keratosis. They will perform a skin evaluation and potentially take a biopsy to make an official diagnosis. They will remove the actinic keratosis if they suspect or determine you have squamous cell carcinoma.

Basal Cell Carcinoma

What it is: Caused by sun damage and typically found on sun-exposed areas like the face, ears, neck, lips, and back of the hands, this type of skin cancer is treatable if caught early. Basal cell carcinoma is the most common type of skin cancer, affecting one in five Americans.

Looks like: Basal cell carcinoma normally appears as a pinkish or reddish patch with raised edges. It also may bleed or scab. "Picture a pimple that seems to heal, only to return," said Dr. Ostad. It can also appear as:

• Flat yellow patches (like a scar)
• Open sores
• Pink or red translucent, shiny bumps
• Raised, itchy, red patches

Treatment: A dermatologist will perform a skin evaluation and possibly biopsy the affected area to determine if you have basal cell carcinoma. Treatment depends on your age and sex, as well as the site, size, and type of lesion. However, it usually involves surgical removal.

Squamous Cell Carcinoma

What it is: Similar to basal cell carcinoma, squamous cell carcinoma is a type of skin cancer that often appears on sun-exposed areas like the face, ear, neck, lip, and back of the hands. It is the second-most common skin cancer in the U.S.

Looks like: Squamous cell carcinoma commonly appears as rough or scaly red (or darker) patches, raised growths or lumps, open sores, and wart-like growths. You'll notice a thick growth that can peel and bleed and may have an irregularly shaped border.

Treatment: Like other skin cancers, squamous cell carcinoma is diagnosed after a skin evaluation and possible biopsy. The most common treatment is surgical removal.

Melanoma

What it is: This serious form of cancer can spread quickly but is curable if caught early. Melanoma occurs when melanocytes, or the cells that give the skin its color, begin growing out of control.

Looks like: The first sign of melanoma is usually a new spot on the skin that is changing in size, shape, and color. The spot may stick out from other ones on your skin. A mole that is melanoma may:

• Be asymmetrical, meaning one half of it does not look like the other
• Be larger than 1/4 inch across in diameter
• Change or evolve rapidly
• Have blurred, irregular, notched, or ragged borders
• Have different colors throughout, including different shades of black and brown or patches that are pink, red, white, or blue

Treatment: Melanoma treatments depend on the stage of your skin cancer. They might include surgery, immunotherapy treatment, targeted therapy drugs, chemotherapy, and radiation therapy.

How To Prevent Skin Cancer

Skin cancer can be preventable. You can lower your risk of getting skin cancer in several ways. UV rays cause most skin cancers, so prevention methods include protecting your skin from sun exposure. You can be exposed to UV rays any time of the year—not just in the summertime—and even when it is cloudy.

Ways to protect your skin from UV rays by:

• Avoiding using a tanning bed, booth, sunbed, or sunlamp
• Staying in the shade
• Using a broad-spectrum sunscreen with a sun protection factor (SPF) of 15 or higher
• Wearing clothes that cover your arms and legs
• Wearing hats that have wide brims
• Wearing sunglasses that block UVA and UVB rays

A Quick Review

New, unusual, or changing moles can be an early sign of skin cancer. Remember to look out for any changes in the color, shape, and size of your moles and follow the ABCDE guide to monitor them. Moles can be benign, but they may signal different types of skin cancer, including basal and squamous cell carcinoma and melanoma.

You should see a dermatologist if you notice your moles changing or any new growths on your skin. You can help lower your risk of skin cancer by practicing sun safety and avoiding indoor tanning. Skin cancer has many treatment options if caught early.