First described in 1889, this is a very interesting skin lesion which grows very rapidly, plateaus and stops growing and then starts to disappear.
It is said that it will grow for about 2 months, then stops growing for 2 months and then disappears after 2 months. As such one can think of it as a benign lesion or a low-grade malignancy, but it does mimic a skin cancer – squamous cell carcinoma. It can look like it visually and histology can be difficult. For this reason, most are excised.
It often looks like a volcano – i.e. a lump with hard matter in the middle or when this matter comes out, like the volcano with a hole in the middle.
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