Nail melanoma most commonly affects the big toe, thumb, or index finger. One of the first signs of nail melanoma is a ...

When Maria Delgado noticed a dark streak under her big toenail ... identified it as an early sign of melanoma, a discovery that transformed her view of toenail health forever.

Unlike other skin cancers, subungual melanoma isn’t linked to sun exposure. It’s most likely to develop in your big toe, thumb or index finger. It usually has a distinct shape, which some may ...