• WARNING: GRAPHIC CONTENT
• Courtney Whithorn developed the nervous habit after being bullied at school  
• The habit became so severe she even ripped her entire nail bed off in 2014 
• When her thumb turned black, she hid it for four years out of embarrassment
• Her biting caused her nail bed such trauma it developed into a rare cancer 
• Despite surgeries to try and save her thumb, it had to be removed last week

올해 5월 한 남성은 손톱 물어뜯는 버릇때문에 패혈증 걸려서 사망했다네요.

WHAT IS ACRAL LENTIGINOUS SUBUNGUAL?

Acral lentiginous subungual melanoma is a form of skin cancer that develops on the palms of a person's hand, the soles of their feet or beneath their nail.

It usually starts as a flat patch of discoloured skin, which can look like a stain, that slowly enlarges over months or years. 

Acral lentiginous subungual is a rare form of skin cancer and makes up less than one per cent of melanoma cases in fair-skinned people, who are more at risk.

Its cause is unclear and not related to sun exposure. It is thought to be triggered by genetic mutations and usually affects people over 40.

As the cancer grows, affected lesions can become several centimetres wide, and contain a variety of brown, black, blue-grey and red colours.

Although smooth at first, the affected skin often becomes thick with an irregular surface, like a wart, and may bleed or ulcerate.

Initial treatment usually involves cutting the lesion out. If the cancer has spread to the lymph nodes, these are often also removed.