Melanoma and nail changes: what to know

Nail melanoma often begins in the pigment-producing cells near the nail root. A brown or black stripe may widen, become uneven, or develop several shades. Pigment can extend onto the cuticle or surrounding skin. The nail may split, lift, thin, or develop a persistent dark area. These changes are not specific to melanoma: injury, infection, medication, and harmless pigment can look similar.

A clinician may examine the nail, skin, and nearby lymph nodes, compare photographs, and decide whether a biopsy is needed. Do not try to scrape, file, or remove a persistent stripe yourself.

Arrange a dermatology assessment for a new dark band or a mark that is changing, especially when it affects one nail without a clear injury. Take a clear photograph with the date and note when the change began. Remove nail polish before the appointment so the nail plate and surrounding skin can be seen. A specialist will explain whether observation, imaging, or tissue sampling is appropriate.

Seek prompt care if pigment is spreading onto the cuticle, the nail is bleeding or breaking down, a dark mark is rapidly changing, or pain and swelling are increasing. Emergency help is appropriate for signs of severe infection such as rapidly spreading redness with fever. These symptoms do not establish melanoma, but delay can make an important diagnosis harder to assess.

Ask whether the pattern could be caused by injury or infection, what features make a biopsy useful, and how the nail will be monitored. Ask how long healing may take if tissue is sampled and when results will be discussed.