ZocdocAnswersWhy is there a black spot on my toe?

Question

Why is there a black spot on my toe?

I'm a 29 year old male. A few days ago, I noticed a black spot on top of my right "index" toe about the diameter of a pea. There was a callus or corn in that area where the skin had dried up and became hard and flaky. I was worried it might be gangrene, but so far it's isolated to that area and hasn't spread. It could be an internal blood blister, but I do not remember injuring my toe. I do not feel any pain in that area, and there is no swelling. Any idea what it might be?

Answer

It's not possible to establish a diagnosis without seeing your toe in person, and you should have it evaluated by a doctor. I can give you, however, some ideas about things it might be. The most concerning potential diagnosis would be a cancer called melanoma. These cancers tend to occur in sun-exposed areas and are characterized by looking like a mole. They can be distinguished by darker color, larger size and irregular borders, but diagnosis is only possible after evaluation by a doctor, sometimes using a biopsy. They can be life-threatening, and should be evaluated by a doctor. Other possible diagnoses include infection, which would be characterized by pain, redness, swelling or tenderness around the area. Loss of sensation can also occur later when the nerves that send pain and touch signals have been destroyed. Warts, although they are usually the same color as your skin, can also be discolored and painless. Finally, it is not uncommon after a local injury such as a cut, scrape, scab or bruise to have discoloration in the skin that can last for several weeks to months. These typically resolve without any intervention. From the description you have given, I would advise you to have the area looked at by your primary care doctor, to rule-out the more serious causes.

This answer is for general informational purposes only and is not a substitute for professional medical advice.

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