When checking your body for signs of skin cancer, don't overlook your nails. The American Academy of Dermatology (AAD) points out that skin cancer -- including melanoma, the deadliest type -- can develop under and around the fingernails and toenails. Though it's rare, it's more common in older people with darker skin.
"When found early, melanoma -- even on the nails -- is highly treatable," Dr. Skylar Souyoul, a board-certified dermatologist in Norwell, Mass says. "The best way to find skin cancer on your nails early, when it's most treatable, is to know what to look for and regularly check your nails."
How to spot melanoma on your nails
Souyoul recommends looking for:
- Dark streaks. They may look like a brown or black band. They're often on the thumb or big toe, but can develop on any nail. Nails might also have a band of color, which can be wide and irregular or dark and narrow.
- Dark skin next to the nail. When the skin around nails is darker, it could be a sign of advanced melanoma.
- Nail lifting from fingers or toes. The nail begins to separate from the nail bed and the white edge at the top will look longer as the nail lifts.
- Splitting. Watch for nails that split down the middle.
- A bump or nodule under your nails.
According to verywell health, as melanoma continues to progress, more streaks may appear, often with different colors. As time progresses, the portion closest to the cuticle may become wider.
Melanoma can also cause bleeding, the formation of a nodule, or deformity to the nail itself as it continues to grow.
RELATED: The Truth About Melanoma
What causes melanoma on nails?
It is currently unknown what causes subungual melanoma. However, there are many risk factors associated with its development. These include:
- Previous trauma to the fingers or toes (a common finding)
- Personal or family history of melanoma
- Multiple moles
- Genetics, such as those with the hereditary condition xeroderma pigmentosa (extreme sensitivity to UV radiation)
- Immune suppression, including organ recipients and people with advanced HIV
How do you get diagnosed?
Although visual examinations are great for noticing any abnormalities, there are limitations, especially since subungual melanoma is so infrequently seen. Because of this, it's often mistaken for other, more common conditions, such as:
- Subungual hematoma, a bruising beneath the nail which lacks the uniformity of subungual melanoma
- Fungal infections (onychomycosis) which more often have dark, non-longitudinal stripes accompanied by yellow or white streaks
- Moles (nevi), which are less likely to appear in streaks
- Deposits of melanin beneath the nail which can occur as a result of pregnancy (as well as chemotherapy or radiation therapy)
"Nail melanoma is often diagnosed at a more advanced stage than melanoma on the skin, making it more dangerous for your health," Souyoul said in an AAD news release. "If you notice any changes to your nails, including a new dark band on your nail, make an appointment to see a board-certified dermatologist."
Treatment for melanoma includes the removal of the tumor, amputation, chemotherapy, radiation therapy, immunotherapy and targeted therapies. Treatment type and outcome is based on the stage of your cancer, which further emphasizes the importance of early intervention.