DA dermatofibroma is a round, brownish to red-purple growth commonly found on the legs. It is also called a histiocytoma. It can occur anywhere, but seems to favor exposed areas. Dermatofibromas feel like hard lumps under the skin. They’re like an iceberg in that there is more under the skin than seen on the surface. Often these start out as red, turning later to brown, and sometimes itch. They probably are a reaction to a minor injury, such a bug bite or a splinter.

We do know that they are harmless and never turn cancerous. For this reason, they are best left alone. If the diagnosis is uncertain, a biopsy may be taken for confirmation. Usually, complete surgical removal leaves a scar that is worse than the Dermatofibroma.

Treatment of dermatofibromas should be considered when they get in the way of shaving or become irritated by clothing. In these cases surgical shaving of the top, punching out the center and maybe freezing with liquid nitrogen can be done. These treatments only destroy the upper part of the growth, and after a few years it may again become noticeable. If this happens, the treatment could be repeated again if desired or the lesion can be completely excised.

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