6 Melanoma Symptoms You Should Never Ignore

You’ve probably heard that melanoma is the deadliest form of skin cancer, but be honest: When was the last time you scanned your skin for any suspicious growths? Even if you’re keeping an eye on a mole or two, you may not realize that the majority of melanomas don’t start from existing moles — and some grow on under a nail, where most people don’t think to look. Knowing what melanoma symptoms to watch for can help you spot this cancer early, when it’s more treatable. 

Look out for the following symptoms of melanoma in between regular skin cancer screenings at your dermatologist’s office. If you’re not sure whether a new growth or spot or a change in an existing one is cause for concern, err on the side of caution and report it to your dermatologist. 

A new spot anywhere on the skin (even where the sun doesn’t shine)

While melanoma can develop in a mole you already have, 70% to 80% of these cancers occur on normal-looking skin. If you perform regular skin self-exams, you’ll get familiar with the location and pattern of your moles and spots and have a much better chance of noticing new growths.

Melanoma can develop anywhere on the body, even in areas that don’t get any sun. Be sure to check your whole body, including areas you can’t see on your own, like your back. Use a full-length mirror and a hand mirror to check them, or have a friend or partner check them for you. 

These are areas people often miss: 

• The bottoms of your feet
• The palms of your hands
• The skin between your fingers and toes
• Your scalp
• Your eyelids
• Behind your ears

A mole with one or more ABCDEs of melanoma traits 

Dermatologists use the ABCDE rule to identify potentially cancerous moles and spots. Here’s what each letter stands for.

• A is for asymmetry. Most melanomas aren’t symmetrical. In other words, one half of the mole doesn’t look like the other half.
• B is for border. Melanomas may have irregular borders, with edges that may be notched or scalloped.
• C is for color. While noncancerous moles are usually a single shade of brown, melanomas can be multicolored. A melanoma may be a combination of tan, black and brown. As the cancer grows, it might look red, white or blue.
• D is for diameter. A mole that’s 1/4 inch in diameter (the size of a pencil eraser) or larger can be cause for concern.
• E is for evolving. Melanoma tends to change over time. Be on the lookout for changes in size, shape, color or elevation. If a mole or growth starts to bleed, hurt or itch, or if it becomes scaly or crusted, those changes count as evolving, too.

An ugly duckling mole

Experts recommend checking for “ugly duckling moles,” moles that look clearly different from nearby moles. An ugly duckling mole may be larger, smaller, lighter or darker than the others. Ugly ducklings can also be lone moles that don’t have any other moles nearby.

Are ugly duckling moles always melanoma? No, but if you spot one, it’s worth bringing to your dermatologist’s attention right away. 

A pink, red, purple or colorless spot

While it’s unlikely to be cancerous, a pink, red, purple or clear growth or spot can be a sign of a rare, aggressive type of melanoma called amelanotic melanoma, especially if it changes over time. It may be the same color as your normal skin color or very close to it, making it difficult for you and even your doctor to detect.

Amelanotic melanomas are easily mistaken for scars or cysts. Fair-skinned people are more likely to develop them.

Nail streaks, bumps or splitting

Rarely, melanoma can develop under or around the fingernails or toenails. Melanoma that grows in the nailbed (under the nail) is called subungual melanoma. The thumb and the big toe, especially of the dominant hand, are the most common sites.

Melanoma in the nail can appear as a brown or black streak or an irregularly shaped spot in the nail, or as a bump or nodule under the nail. As the disease advances, the nail may lift and separate from the nail bed and split. You may notice dark skin next to the nail.

Ocular melanoma symptoms (floaters, iris spots and others)

Ocular melanoma, or melanoma in the eye, is very rare. It’s also hard to detect because oftentimes there are no signs that you can see in the mirror, and many people don’t have symptoms in the early stages — a good reason to have regular eye exams. 

Signs and symptoms of ocular melanoma include blurred or changed vision, floaters (drifting specks in your vision), flashes, a dark spot on the iris (the colored part of your eye), a blind spot in your peripheral (side) vision and a change in the shape of one of your pupils.

Melanoma strikes people of all races and ages. Performing a simple skin self-exam once a month to look for melanoma symptoms takes only a few minutes. If you notice something suspicious, don’t try to decide if it’s likely to be melanoma or not — that’s what your dermatologist is for. Be on the safe side and make an appointment.

Medically reviewed by Andrew Jaffee, MD

Written by Jessica Brown, a health and science writer/editor based in Nanuet, New York. She has written for Water’s Edge Dermatology, Prevention magazine, jnj.com, BCRF.org, and many other outlets.