many causes and are more common in people with darker skin tones. However, a new or changing dark streak can occasionally be a sign of subungual melanoma, a rare form of skin cancer that develops beneath the nail.
What to do: Do not assume that every dark streak is melanoma, but have a new, widening, irregular, or changing streak evaluated by a dermatologist—especially if the pigment extends onto the surrounding skin.
Other Nail Changes to Watch For
White spots: Often caused by minor trauma to the nail rather than a
