Commonly found on the legs, a dermatofibroma is a round, brownish to red-purple growth. It is also known as a histiocytoma. It seems to favor exposed areas but it can occur anywhere. Due to the parts of the body being more exposed you are more likely to contract this skin disorder during the summer months. Typically dermatofibromas will feel like hard lumps when felt under the skin. There is more under the skin than seen on the surface much like an iceberg. The conclusion that there is nothing major to worry about is often a result of this deception. Sometimes these will itch and they typically start out red but later turn brown. They can be a reaction to any minor injury including bug bite or splinter.


The site of a trauma such as an insect bite is generally the area where histiocytoma starts. The lesion typically starts as a firm papule or a button like tumor. Over time their size may vary slightly and they may be slightly tender. It may be confused with melanoma due to the rapid growth and brown pigmentation.

Upon lateral compression fibrous histiocytomas tend to dimple inward. This helps make them distinguishable from nodular melanomas which upon lateral compression protrude outward.


The lower legs is where dermatofibromas usually appear after developing slowly. The assisting characteristics are the sign through which you can distinguish this skin disorder. You will be able to seek immediate treatment by being aware of these characteristics. There are various characteristics of these small, hard, raised skin growths:

  • While they may appear on the arms or trunk they are typically found on the lower legs.
  • They may change colors over time including red, pink, purplish, gray or brown.
  • They rarely grow larger than a fingernail and may be as small as a BB pellet.
  • They may be tender, painful or itchy but this is rare since they are often painless.
  • When pinched they usually dimple inward.


By examining a nodule a physician can often diagnose a dermatofibroma. A biopsy is performed if a physician wants to be certain of the diagnosis, if the growth doesn’t look like a typical dermatofibroma or if a bleeding sore appears on the surface. A biopsy is examined under a microscope after either a portion or all of the nodule is removed. If you are unsure about the effects of treatment it is crucial to ask your physician questions. This way before treatment starts you will have peace of mind.


Since they do not pose any risk, dermatofibromas do not require any treatment. Dermatofibromas may be removed in some patients prefer. If the growth is unsightly this may be desirable, also if it is an inconvenient location or if it is painful or itchy. In the long run getting the dermatofibromas removed will work to the patient’s advantage.

  • It is best to ignore dermatofibromas. A piece may be removed for tissue analysis if the diagnosis is uncertain.
  • Since they are deep they will usually leave a scar if they are removed surgically.
  • Only the upper part of the growth is destroyed with liquid nitrogen freezing. As a result it may become noticeable again after some years. However, these regrowths can often be handled by another freezing since they are slight.

Surgically and freezing are two main ways to remove a dermatofibroma. Total surgical removal requires cutting it out below the surface level of the skin since they grow deep. A noticeable scar is usually left by this process. Shaving the top off with a surgical knife or by freezing it with liquid nitrogen is an alternative method that will make it flat to the surface of the skin. With these procedures the deeper layers of the skin remain but the top layers are destroyed. After several years the nodule may grow back again. This makes it apparent that there has not yet been a permanent solution discovered for this type of skin disorder.

Seeking Medical Attention

When you have any new skin growth it is always wise to see a physician to get an accurate diagnosis, especially if you have something that either changes color or is dark brown or black. If the growth bleeds, grows quickly or becomes painful then you should see a doctor immediately.


Dermatofibromas do not become cancerous and they are benign or no cancerous growths.

Leave a comment

Latest Articles

Any Query?