Karolina Jasko was a high school senior when, while getting her nails done, she saw a black line running down her right thumbnail.
She had been getting acrylic nails applied once or twice a month on top of her real nails that were cured with ultraviolet (UV) light, but never noticed any marks before that day in December 2016.
At first, she brushed it off as bruise but, one week later, when her finger began swelling and turning red, she went to her doctor in Chicago, Illinois.
After being referred to a dermatologist, and having a biopsy done, Jasko learned that the dark line on her nail was actually melanoma, or skin cancer.
Jasko, now 21, who competed in the 2018 Miss USA pageant as Miss Illinois, told DailyMail.com that she had to have her entire thumbnail removed and was so ashamed of it that she covered it with a Band-Aid for nearly a year.
Karolina Jasko, 21 (left and right), from Chicago, Illinois, first saw a black line running down her thumbnail during a nail appointment in December 2016. However, she and the nail tech brushed it off as a bruise
One week later, when Jasko's finger began swelling and turning red (pictured), she visited the doctor, fearing she had contracted an infection from the nail salon
Jasko didn't see the line on her nail until that appointment at the nail salon when the nail tech began applying her new acrylic nail.
'We kind of both just brushed it off, and thought it was a bruise,' she said. 'A few days later, my finger swelled up really bad and I automatically thought I got some sort of infection from the nail salon.'
Jasko's mom helped her take her acrylic nail off, and that's when Jasko remembered it was the same thumb that had a dark line down the center.
She booked an appointment with her primary care doctor, who said the dark pigmentation could be a sign of skin cancer.
That same day, Jasko went to the dermatologist referred to her by her doctor, who ordered a biopsy.
Within a few days the results came back: the 18-year-old had skin cancer.
Nail melanoma, or subungual melanoma, is a cancer that occurs in the tissues of the nail bed.
These melanomas are most commonly found on either the thumbs or big toes, but they can form on any fingernail or toenail.
Symptoms include a vertical band on the nail that's a different color than the nail, dark pigmentation that covers the nail, nail brittleness, and bleeding where the pigmentation is.
Jasko was diagnosed with nail melanoma, or subungual melanoma, is a cancer that occurs in the tissues of the nail bed. Pictured: Jasko's thumb after surgery to remove the nail matrix
The cancer is often difficult to diagnose
