Should You Be Worried About a Black Toenail?

Is a black toenail something I should be concerned about? I heard it could be melanoma. I think my grandmother may have had it but I can’t remember?

Melanoma is a type of skin cancer that accounts for approximately1% of skin cancers. It affects the cells (melanocytes) that give our skin its color. It’s the most dangerous and aggressive form of skin cancer. It spreads quickly and can be life-threatening but potentially treatable form of cancer if diagnosed and managed at an early stage.

This form of cancer has a unique characteristic of spearing (metastasized) widely to other body parts from the area of its occurrence and can be the only sign prior to developing symptoms. This finding can be important for a healthy, asymptomatic person.

Are there different types of Melanoma?

The most common type of melanoma is superficial spreading melanoma. It tends to spread across the surface of the skin, has uneven borders, and varies in color from brown to black, pink, or red. However, the most common form that appears on the lower extremity (foot) is acral lentiginous melanoma and most commonly affected part in the foot is the big toe. Around 3-15% of melanomas occur on the foot.

The concern about melanoma compared to other skin cancer is that it invades deep and may look unchanged on the skin resulting in a delay in treatment and ultimately a poor prognosis.  With early diagnosis, the 5-year survival rate approaches 95%.

What are some common warning signs?

The cancerous cells underneath the nails can look like purple, red, brown, or black bruise typically referred to as patriotic colors. These also tend to look like dark streaks that grow vertically in the nail and can leach into the surrounding skin.  To help identify common signs an acronym was created called CUBED.

• Colored: A lesion has a color different to the rest of the skin.
• Uncertain: A lesion does not have a definite diagnosis.
• Bleeding: A lesion on the foot or under the nail bleeds or leaks fluid.
• Enlargement: A lesion or ulcer grows or gets worse despite treatment.
• Delay: A lesion takes longer than 2 months to heal.

Other warning signs for foot melanoma include:

• A sore that does not heal.
• Pigment spreading from the border of a lesion to surrounding skin.
• Redness or new swelling beyond the border of a lesion.
• Changes in sensation, such as itchiness or pain.
• Changes in the surface of a mole, including scaling, oozing, bleeding, or the appearance of a bump.

How do I know if my birth mark, sun spot or freckle isn’t melanoma?

Traditionally ordinary Moles are evenly colored, have sharply defined edges and are round or oval in shape. They can be flat or raised and are less than 6 millimeters (1/4″) in diameter (about the size of a pencil eraser). Melanomas have an irregular appearance and are usually larger than an ordinary mole.

Could my black toenail be something else?

• Infection: bacterial and fungus (onychomycosis). Microorganisms especially fungus secrete waste that can appear dark.
• Elective procedure: ingrowing toenail.
• Runners or Marathon toe: the tiny vessels in the nail bed become damaged due to high, prolonged impact which compromises the integrity of the nail apparatus resulting in a bruise appearance.
• Trauma or injury: stubbing toe or dropping an object on foot or toe.
• Poor hygiene
• Poor shoe fitting
• Melanonychia: common in light and dark skin individuals where the cells that contribute to skin color cluster in the (proximal) nail fold resulting in well-defined vertical bands or striations in the toenail. (see picture)
• System disease: diabetes, thyroid, other autoimmune, liver, anemia, vascular disease.

What are some of the risk factors?

• UV light both artificial and natural (most common)
• Existing moles
• Pale skin, freckles, and light hair
• Family or personal history of melanoma or other skin cancers.

Who should I see to get evaluated?

A foot doctor is recommended, but due to the aggressive nature of melanoma, being seen by the first available healthcare provider is highly recommended. Earlier detection of suspicious lesion(s) may facilitate earlier referral for expert assessment and definitive diagnosis by a dermatologist or oncologist.

Where can I find more information?

The American Melanoma Foundation (AMF) was founded in Southern California in1990 by a group of melanoma patients and their relatives who believed in the importance and ever-growing need for support of specific research for new treatment approaches in melanoma, one of the most serious of all cancers.

melanomafoundation.org