I would definitely get that checked out. Here is an image of what melanoma can look like when it is located under the fingernails.
It is possible that it is nothing but there is a type of melanoma called subungual melanoma which develops under the fingernail. Dr. Kevin Berman describes this type of melanoma in one of his posts:
"Another type of melanoma that is often overlooked is subungual melanoma, which is melanoma under the fingernails or toenails. This type of melanoma can appear as a nodule, often appearing like the amelanotic melanoma described above. In this case, it is often destructive to the nail plate and can cause pain. More commonly, subungual melanoma appears as a dark longitudinal band running the length of the nail. It can be several millimeters wide or can affect a much wider width of the nail. This melanoma is often overlooked because it is very common for people with dark colored skin to have darkly pigmented longitudinal streaks (termed benign melanonychia) in the nail. These are not dangerous."
So yes definitely get this checked out. Let us know how things go for you. Thank you for your question.
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