Jean Skinner, a nail technician from Essex, has shared a photograph of a client’s nail on Facebook in order to raise awareness about the little-known symptoms of melanoma (skin cancer).

In the image, a thumbnail is visible, with a strong dark line running through the middle. Captioning the picture, Skinner writes: “I had a walk-in nail client a couple weeks ago, and she had a straight dark vertical stripe down her nail.”

As soon as the client sat down, she asked Skinner to paint her nails with a varnish dark enough to cover the stripe, believing it to be due to a lack of calcium or a blood blister.

Skinner, however, took one look at the nail and realised that things were far more serious.

“This is melanoma,” she writes. “I did not want to frighten my client, but I told her she needed to see her doctor immediately.

“She called me today to tell me that, yes, the dark stripe indicated a very aggressive melanoma, and that it has already spread to her lymph nodes.”

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Skinner, angry that so many nail salons had offered her client false diagnoses in the past, goes on to reveal that the woman’s prognosis is, sadly, not looking good. If she had visited a doctor sooner, there is a chance that the melanoma could have been caught earlier and treated far more easily.

“Please pay attention to abnormalities in your nail beds,” she asks her Facebook followers. “Odd changes in your nails can very likely be nothing to worry about, but sometimes it is an indication of a very serious disease”

Skinner adds: “And please keep an eye on the nail beds – toes and fingers – of your elderly loved ones and your loved ones that aren't physically able to notice changes in the nail beds.

“Early diagnosis can make all the difference in the world!”

According to the NHS, dark stripes running down the nails (linear melanonychia) are fairly common, particularly in black people over the age of 20. In most cases, they are perfectly normal and there’s nothing to worry about.

However, dark stripes shouldn't be ignored because “it can sometimes be a form of skin cancer that affects the nail bed, called subungual melanoma”.

They continue: “Subungual melanoma usually only affects one nail. It will also cause the stripe to change in appearance – for example, it may become wider or darker over time and the pigmentation may also affect the surrounding skin (the nail fold).”

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Melanoma is a type of skin cancer that can spread to other organs in the body – and it is the fifth most common form of cancer in the UK. Around 13,500 cases are diagnosed each year, and more than a quarter of cases are diagnosed in people under the age of 50.

The main treatment for melanoma is surgery – and, if it’s diagnosed and treated at an early stage, this is usually the most successful form of treatment. However, if it isn’t caught quickly, treatment is mainly used to slow the spread of the cancer and reduce systems, using medicines and checkpoint therapies.

It's important that you regularly check your skin and nails. And, if you experience any changes, that you visit your doctor immediately so that they can rule out melanoma.

Find out more on Cancer Research UK now.

Images: Suhyeon Choi