Knowing if a black spot on your toe is melanoma can be life-saving. This aggressive skin cancer can show up anywhere on the body, including on the toes, which are often overlooked in routine skin examinations. It’s essential to know how melanoma on the toe looks and feels, so you know when to seek medical advice.

Melanoma is sometimes called cutaneous melanoma. It’s a type of cancer that grows in melanocytes, a cell that produces melanin. Melanin is the pigment in skin that gives it color, contributing to a range of skin tones from light to dark. Melanin also protects the skin’s deeper layers from some damaging effects of sun exposure.

Melanoma isn’t as common as basal cell carcinoma or squamous cell carcinoma, two other types of skin cancer. However, melanoma can be dangerous because it’s more likely to spread to other areas of the body if it’s not found and treated early.

Although skin cancers such as melanoma are often linked to sun exposure when skin cancer appears on feet, it is often caused by other risk factors — genetic (inherited) traits or a family history of melanoma, inflammation, irritation, viruses, or chemicals.

Early diagnosis and treatment of melanoma is essential. Here’s more about what to look for if you see a black spot on your toe and are concerned about melanoma.

What Does Melanoma on Toes and Feet Look Like?

There are many different types of melanoma, any of which can develop on the toes or other parts of the feet. Melanoma can appear as a dark spot — on the toe, in between toes, under the toenail, or on the foot, including the sole.

If you notice a new black or dark spot on your toe or foot — or you have an existing mole or birthmark that has changed size, shape, or color — that could be a sign of melanoma. Warning signs of melanoma on the toe, toenail, or foot include a dark spot with characteristics that can be more easily remembered using the “ABCDEs of melanoma:”

• A — Asymmetry is when one half of a spot looks different from the other side.
• B — The border of the spot is irregular or blurred.
• C — Color is irregular and may include brown, black, red, pink, white, or blue and may spread to the surrounding skin.
• D — Diameter is more than a quarter of an inch, or the size of a pencil eraser, although melanoma lesions can also be smaller.
• E — Evolving means the spot continues to change.

Any mole, birthmark, or spot that is itchy, painful, sore, swollen, bleeding, oozing, or has an unusual, crusty, scaly, or bumpy texture can indicate symptoms of melanoma and should be examined. Melanoma tends to look different from normal moles or birthmarks.

When looking for melanoma on your toes, check for dark streaks on your nails (particularly the big toe and the thumb), dark skin surrounding the nail, bumps under the nails, and nail splitting or lifting. These can be signs of melanoma on the nails.

Acral Lentiginous Melanoma

Acral lentiginous melanoma (ALM) is a rare type of melanoma that only occurs in about 5 percent of all melanoma cases. ALM can develop anywhere on the body, but it’s a type of melanoma known to occur especially in the palms of hands, soles of feet, and under the fingernails or toenails.

Although ALM is rare, the Melanoma Research Foundation has found it occurs in about 50 percent of melanoma cases that develop in Asians and people with darker skin tones. Research suggests that ALM is not caused by sun exposure.

ALM on the sole of the foot can sometimes look like a bruise and grows more slowly than some forms of melanoma. However, death rates for ALM are higher than other types of melanoma because it often goes undetected or is misdiagnosed until it has spread. In more advanced cases ALM spots can be bumpy and rough to the touch. When ALM forms under the toenail, it can appear as a dark, vertical band under the nail.

Subungual Melanoma

Subungual melanoma, a rarer subtype of ALM, occurs primarily under the thumbnail or under the toenail of the big toe. Like ALM, it’s not known to be caused by harmful ultraviolet radiation from the sun. This type can appear as a brown or black band with blurred or irregular edges. However, almost 50 percent of subungual melanomas don’t have any color at all, which makes it difficult to diagnose.

Because both subungual melanoma and ALM in toenails can look like bruised nails and may cause nails to split open, it’s important to see a doctor if you notice a dark spot in your toenail and have not experienced any type of injury to the toe.

The Importance of Early Detection of Melanoma

Melanoma on the toe or foot is very treatable if discovered early. In fact, melanoma can usually be cured if it’s treated before it has spread to another part of the body. Along with yearly skin examinations by a dermatologist, many dermatology experts recommend self-examination each month to see if any new moles have developed on your skin or if any existing spots have changed.

However, melanoma on the nails is typically diagnosed when the cancer is at a more advanced stage. Many people remember to check their skin for signs of skin cancer but often forget to check their nails. The best way to diagnose skin cancer early is to check your skin and nails regularly for any changes that may be signs of melanoma.

A self-examination can be done by looking closely at your skin and nails in a well-lit area in front of a full-length mirror. To detect melanoma on the toes or feet, it’s important to carefully look at each toe, including the skin between the toes. You must also look at the soles of your feet. For some people, this may be difficult, and you may need a hand mirror. You can also ask your partner, another family member, or a friend to look at parts of your body that are hard to see, including the bottom of your feet.

Diagnosing Melanoma on the Toe or Foot

Don’t hesitate to contact your doctor right away if you notice any concerning spots on your toes, feet, or anywhere else on your body. If your doctor suspects you have melanoma, you will undergo tests such as imaging tests and skin biopsy. If melanoma is found, you’ll likely have a biopsy of nearby lymph nodes to determine if the cancer has spread.

Melanoma treatment may include surgery, immunotherapy, targeted therapy, chemotherapy, or radiation therapy, depending on your condition.

Other Causes of Black Spots on the Toes

A dark spot on the toe or somewhere else on the body isn’t necessarily melanoma. In some cases, a dark spot may be caused by hyperpigmentation.

In people with hyperpigmentation, the skin produces abnormal amounts of melanin. Spots can develop that may look black, brown, red, pink, blue, or gray. Spots that form due to hyperpigmentation are sometimes known as liver spots, sun spots, or age spots. They are a sign of damaged skin and can be caused by many different health conditions, including:

• Adrenal gland disorders, such as Addison’s disease
• Skin injuries
• Vitamin deficiencies
• Genetics (inherited traits)
• Some medications that cause light sensitivity
• Damage from the sun
• Hormonal changes, including a condition known as melasma that can occur during pregnancy

Talk to Your Doctor

Keeping an eye on any unusual dark spots on your toes, toenails, and feet can be life-saving. Regularly checking your skin, along with professional skin exams, helps find changes early — especially in areas like the nails and soles that are easy to overlook. If you have an unusual black spot, tell your doctor right away so they can examine you to determine the cause and appropriate treatment options.

Find Your Team

MyMelanomaTeam is the social network for people with melanoma and their loved ones. On MyMelanomaTeam, more than 1,200 members come together to ask questions, give advice, and share their stories with others who understand life with melanoma.

Have you ever found a black spot on your toe? Did you call your doctor right away? Share your thoughts in the comments below, or start a conversation by posting on your Activities page.