How a long white line on your finger nail could mean you’re at a much higher risk of kidney CANCER

Faint lines on your fingernail could indicate a rare genetic condition that puts you at risk of kidney, skin, and eye cancers, new research suggests.

Scientists at the National Institutes of Health (NIH) have discovered that 88 percent of people with a rare genetic disorder that can lead to cancer have abnormal nail markings, including a thin white line running the length of the nail.

The genetic disorder, which is believed to run in fewer than 100 American families, increases the odds of a rare type of eye cancer, as well as lung, skin and kidney cancer.

Called BAP1 tumor predisposition syndrome, it affects a gene that prevents the body’s cells from growing at a rapid rate, and developing into tumorous masses.

The gene also plays a crucial role in repairing DNA damage to cells, which protects against the growth and spread of cancer cells. 

The researchers happened across the finding in a study looking at the gene, called BAP1, for mutations: 41 of 47 people had an abnormal line on a nail, and further probing found that 39 of them had a benign tumor. 

Of the total number of people in the study with confirmed tumor predisposition syndrome, 87.2 percent had tumors in their nail beds.

Alexandra Lebensohn, a National Cancer Institute researcher who helped conduct the study, said: ‘When asked about nail health during a baseline genetic assessment, a very astute patient reported that he had noticed subtle changes in his nail.

‘His comment prompted us to systematically evaluate other participants for nail changes and uncover this new finding.’

The most distinctive finding was a small, thickened area of skin under the nail, along with a white band running down the nail, which is consistent with onychopapilloma, a type of benign tumor.

The tumor is believed to affect the production and distribution of keratin, the type of protein that makes up the nail. 

The white lines represent higher levels of keratinization, or areas where the nail has been lifted or distorted by the tumor underneath.  

Thirty-nine of 47 study subjects were found to have onychopapilloma, most of them males and mostly on the thumbnail. Onychopapilloma is rare in the general population.

Dr Edward Cowen, a dermatologist at NIH’s National Institute of Arthritis and Musculoskeletal and Skin Diseases, said: ‘We believe the presence of nail changes that suggest onychopapillomas on multiple nails should prompt consideration of a diagnosis of BAP1 tumor predisposition syndrome.’

Their research was published in JAMA Dermatology.  

About 36 percent of people with the genetic disorder have uveal melanoma, a type of cancer that begins in melanin, which makes dark pigments in the middle layer of the wall of the eye. The uvea includes the iris.

It accounts for only about 5 percent of all cases of melanoma in the US.

Roughly a quarter of people with the syndrome have mesothelioma, according to the NIH. Mesothelioma is an aggressive cancer that develops in the thin layer of tissue that covers most of the internal organs, most commonly seen in the lining of the lungs.

And 10 percent of people with the condition were found to have kidney cancer.

BAP1 tumor predisposition syndrome is rare and still under investigation. Around 70 families in the US are known to have the genetic mutation that puts them at higher risk for cancer.

Most of the BAP1-related cancers tend to be more aggressive and triggered earlier in life. 

In cases of malignant mesothelioma, the age of onset in people who are predisposed is 55 years, compared with 72 years for people without that predisposition.

At the same time, several studies have reported that patients with a BAP1 mutation have an overall survival rate that is seven times longer than those without a genetic predisposition.