LOS ANGELES (CBS) – Most people know to get freckles and moles checked out by a doctor, but a small spot under your nail could be just as dangerous.

Lisa Sigell from our sister station KCBS/CBS Los Angeles, talked to some experts about a potentially deadly form of nail cancer.

Dr. Dana Stern is a nail specialist.

She’s checked her patient Julie’s index finger, but there’s no nail there now.

It was removed after she was diagnosed with nail cancer.

Technically, it’s not the nail itself, but a malignant melanoma of the nail bed or the skin underneath her nail.

“There was a brown line across my fingernail for, I would say, two or three years,” Julie said.

“Just like you have moles on your skin, you can have a mole on your nail matrix, which is where the nail grows from,” Dr. Stern said.

When the brown line on Julie’s nail began to change, she finally sought the opinion of a doctor.

“It started as a light line, but then eventually it started getting broader, and the middle of it started to get really black,” she said.

Julie’s cancer was caught early, but Dr. Stern warns that you need to be vigilant.

At the beginning of a manicure or pedicure, when the polish comes off, look for any changes.

More often than not, a dark line or spot is simply a bruise.

However, if you don’t remember getting the injury, or if the spot simply doesn’t go away, you should see a doctor.

“People will sometimes develop an early melanoma and think it’s an injury, and they don’t even really realize that they’re supposed to go to their dermatologist,” Dr. Stern said.

The thumb, big toe, and index finger are the most common nails affected.

There are some other signs a stripe may be nail cancer or melanoma.

  • If the stripe is very dark
  • If it has blurred borders
  • If it’s changed shape over time

The patient’s history also plays a role as well.

Treatment depends on the stage of the cancer ranging from removing the melanoma and the tissue around it, to amputation of the fingertip.

For a long time, Julie wore a Band-Aid to hide her finger after surgery.

Now, she feels differently.

“Just be proud that you’re a survivor,” she said.

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