In many cases, dermatofibromas are asymptomatic. However, the following are the signs and symptoms may be present:

• Dermatofibromas usually develop as single nodules mostly in the lower legs.
• These are firm to touch, whereas some nodules may also get hard.
• These measure 0.5–1 cm in diameter similar to size of a small lentil.
• The surface of the affected skin can appear scaly. The overlying skin can get tethered.
• The size of the nodule tends to remain intact after the initial growth.
• The affected area is tender to touch and can cause pain and itchiness in some cases.
• When touched, the nodule may appear to be freely moving and feels like pebble.
• The affected area can turn grey, pink, orange, red, purple, blue, black or brown in color.
• Atypical variants may present similarly with melanoma, vascular tumors and psoriasis [8].

• Fishing

  Recently, CD99 was shown to be diffusely expressed in DF thus providing another potential option for distinguishing the two tumors. [7] Advanced techniques for distinguishing the tumors include fluorescent in situ hybridization (FISH) probe analysis for [idoj.in]

• Insect Bite

  It arises spontaneously without a known cause or after a minor trauma, such as an insect bite. A 39-year-old Asian woman complained of a palpable mass and tenderness in the right upper eyelid. [ncbi.nlm.nih.gov]

  Some physicians believe dermatofibromas form as a reaction to previous injuries such as insect bites or thorn pricks. [yourkidsdoctor.com]

  Aside from insect bites, they may be caused by a pin prick, the jab of a thorn or after receiving an injection. What’s the best treatment option? Dermatofibromas are best ignored. [skinsite.com]

  The cause is unknown but some believe it arises at the site of a minor injury, especially an insect bite or thorn prick. Once developed, they usually persist for years. [randyjacobsmd.com]

  It has no exact cause, but may appear after a minor skin gash or laceration, like an insect bite, splinter, or a thorn prick. Dermatofibroma may appear on any part of the body, but usually it is found on the arms or legs. [pchrd.dost.gov.ph]

• Skin Lesion

  A case with a pigmented skin lesion that was diagnosed as a blue naevus on clinical and dermoscopic grounds and histopathologically confirmed as a dermatofibroma is presented. [ncbi.nlm.nih.gov]

  The real reason for formation of these skin lesions is unknown. Microtrauma of the skin can be cited as one of the possible causes. [orshospital.rs]

• Papule

  Dermatofibroma is a firm, skin-colored or reddish-brown sessile papule or nodule. It arises spontaneously without a known cause or after a minor trauma, such as an insect bite. [ncbi.nlm.nih.gov]

• Erythema

  Dermatofibroma Differential Diagnosis The differential diagnosis for Dermatofibroma consists of distinguishing the disease from other disorders like Piloleiomyoma, Neurofibroma, Tophus, Hypertrophic Scar, Erythema Elevatum Diutinum and Neurilemmoma that [hxbenefit.com]

  : The most common vascular structures This glossary term has not yet been described. are erythema, dotted vessels tiny pinpoint vessels, comma vessels linear curved short vessels dermal nevi, and hairpin vessels This glossary term has not yet been described [dermoscopedia.org]

  Erythema or hyperpigmentation is typical in colored skin and can lead to anxiety in some patients. The more serious complications that can occur are infection, delayed hypopigmentation, persistent erythema, and prolonged healing. [faoj.org]

  Less frequently, an atypical pattern may be seen, including peripheral atypical pigment network, erythema, vascular structures, central red-bluish homogeneous area and chrysalis.[3] Recently, Ferrari et al. described a group of atypical "non DF like" [ncbi.nlm.nih.gov]

  Dermatologic Manifestations of Juvenile Xanthogranuloma Cutaneous Lipomas Dermatologic Manifestations of Merkel Cell Carcinoma Dermatologic Manifestations of Metastatic Carcinomas Dermatologic Manifestations of Neurilemmoma (Schwannoma) Epithelioid sarcoma Erythema [drugsdetails.com]

• Skin Disease

  Keywords: Histiocytoma, benign fibrous; Histiocytoma, malignant fibrous; Skin diseases Abstract O dermatofibroma é um tumor fibrohistiocitário benigno, comum e facilmente diagnosticado quando apresenta os achados clinicopatológicos clássicos. [ncbi.nlm.nih.gov]

  Non-malignant skin disease. References ↑ Humphrey, Peter A; Dehner, Louis P; Pfeifer, John D (2008). The Washington Manual of Surgical Pathology (1st ed.). Lippincott Williams & Wilkins. pp. 492. [librepathology.org]

• Irritability

  Usually, they don’t cause any other symptoms but occasionally, if they are in a location where they are easily irritated, they may cause some itching or slight pain. [skinsite.com]

  Some people find it irritating or unattractive and want to get it removed. A dermatologist can usually perform this procedure in-office under local anesthesia. [buoyhealth.com]

  Biopsy: If the growth is bleeding, abnormally shaped, or irritated, or it has a sore on top of it, doctors may want to do a biopsy. [medicalnewstoday.com]

  DF with balloon cell change, likely secondary to persistent irritation, should be added to the differential diagnosis of cutaneous primary and metastatic neoplasms showing balloon cell degeneration such as balloon cell melanocytic nevi and renal cell [ncbi.nlm.nih.gov]

• Confusion

  When these changes occur, they may be confused with melanoma. Therapy In general, 90% of the time, no biopsy or therapy is necessary for classic dermatofibromas. [randyjacobsmd.com]

  Sometimes a dermatofibroma is confused with a mole. The way to tell the difference between the two is to pinch the bump. If you pinch a dermatofibroma, it creates a dimple because it is attached to the underlying subcutaneous tissue. [verywell.com]

  Eruptive xanthomas are characterized by a lacelike infiltrate of extravascular lipid deposits between collagen bundles (Figure 3). 2 Granular cell tumors are composed of sheets and/or nests of large cells with abundant eosinophilic cytoplasm and may be confused [mdedge.com]

  Dermatofibromas are classed as benign skin lesions, meaning they are completely harmless, though they may be confused with a variety of subcutaneous tumours. [7] Deep penetrating dermatofibromas may be difficult to distinguish, even histologically, from [en.wikipedia.org]

Careful examination of the nodule forms the basis of the diagnosis. A pinch test is performed that gives an idea about the nature of the fibromas. In this test, the area of the lesion is squeezed from the sides which causes dimpling of the overlying skin.

The dermatofibromas are also studied under the dermatoscope. When viewed through a dermatoscope, a typical fibroma appears as a pigmented network with a white patch in the center.

A biopsy of the fibroma may be required if the above tests do not give any definite conclusion. The use of Positron Emission Tomography (PET) with radiotracer FDG can demonstrate dermatofibroma within the chest wall effectively [9].

Dermatofibromas usually do not require any treatment. These do not go away by themselves and therefore, individuals may want to get it removed for cosmetic purposes. In addition, certain individuals may also experience pain and pruritus and may thus want to get rid of it. These nodules are harmless and do not cause any life threatening conditions. The following are the procedures employed for removing:

• Elliptical excision or punch biopsy is the most desired method as the chances of recurrence of the nodule after such procedures is rare.
• Methods such as shave excision or cryotherapy present high risk of recurrence.
• Carbon dioxide laser treatment for multiple dermatofibroma lesions [10].

Dermatofibromas are benign in nature and usually harmless. They stay for several years together without causing much of problem. Rare variants of dermatofibroma like the atypical, aneurysmal and cellular variants can rarely metastasize though [6]. These variants have an average recurrent rate of 20% [7]. Such a condition does not turn fatal and the prognosis is generally good with treatment. However, in certain cases, the nodules can grow back even post treatment. The success rate of the treatment procedures vary with the type of method employed to remove the growth.

Complications

Dermatofibromas usually do not give rise to any complications. The growth been benign in nature does not cause harm to the individual. In rare cases, fibromas can cause the following complications:

• Subcutaneous nodules
• Hyperpigmentation

The exact cause of dermatofibromas is still unclear. Whether the growths occur due to neoplasm or any reactive processes is still an unanswered question. However, it has been reported that such growth can develop at the site of injury caused by insect bite or thorn prick.

Dermatofibromas are a common condition mostly affecting the women than men with the ration of women to men of 4:1. Such a condition can strike women at any age with the incidence rates higher in the younger population.

Dermatofibromas rarely affect children. A statistical study show that dermatofibromas are diagnosed within the age group of 20-49 years old in 80% of cases [3].

The exact mechanism behind the development of dermatofibromas is still unclear. However, by studying the nature of the fibrous growth it appears than such a condition occurs due to a neoplastic process rather than a reactive tissue change [4]. It can also occur due to distorted protein kinase activity [5]. In majority of the cases, dermatofibromas appear as a single nodule. But, in some cases it may develop into several nodules and is most common in individuals with a suppressed immune system. Dermatofibromas are also associated with the following disease conditions:

• Systemic lupus erythematosus
• Dermatomyositis
• Down syndrome
• Graves’ disease
• Leukemia
• Multiple myeloma
• Crohn disease
• Atopic dermatitis
• Myasthenia gravis
• Myelodysplastic syndrome
• Cutaneous T–cell lymphoma

Individuals with the above mentioned diseases may also develop dermatofibromas as a secondary complication.

So far no methods have been developed for preventing the occurrence of dermatofibromas. Since the etiology behind the development of such a condition is unclear, there is no way its onset can be prevented.

Dermatofibroma also known as superficial benign fibrous histiocytoma is a benign tumor that develops on the skin’s surface. It is also regarded a clonal proliferative tumor due to its distinct methylation patterns seen in the polymorphic X chromosomes [1].

The common site for such benign fibrous growth is the lower legs. In addition, they can also occur in the bone, gastrointestinal tract, airways, genitourinary and intracranial locations. This condition typically affects more women than men.

Dermatofibromas can stay for several years and not produce any symptoms. These are harmless growth characterized by firm nodules that are yellow–brown in color. Dermatofibromas are considered the most common painful tumor in man [2]. In dark colored individuals, the nodules may appear even pink in color.

Definition

Dermatofibromas are defined as development of small fibrous growth on the skin surface. These are benign in nature and harmless. This is a common condition and is in no way associated with cancers of the skin. Usually these growths are not painful and do not cause any discomfort. Dermatofibromas usually develop as single growth on the skin surface; whereas in some cases, it may present as multiple growth.

Cause

The exact mechanism that triggers the development of dermatofibromas is unclear. These can develop at small site of injury due to insect bite or thorn prick.

Symptoms

Dermatofibromas measure about 0.5–1 cm in diameter. The affected area turns pink, brown, black or red in color. The area is tender to touch and may cause pain and itchiness in some cases. When the nodule is touched it feels like pebble and is freely movable.

Diagnosis

The examination of the nodule is usually the first diagnostic procedure. The fibrous growth is observed under a dermatoscope. A typical nodule appears as a group of pigmented network with white patch in the center region. A biopsy of the nodule may be required when no appropriate diagnosis can be made.

Treatment

Dermatofibromas usually do not require any treatment unless individuals want to get it removed for cosmetic purpose. In addition, such nodules may be a cause of great discomfort requiring immediate removal. The method of punch biopsy is preferred over cryotherapy as with the former procedure the rate of recurrence of the nodule is very rare.

1. Chen TC, Kuo T, Chan HL. Dermatofibroma is a clonal proliferative disease.J Cutan Pathol. 2000; 27(1):36-9
2. Naversen DN, Trask DM, Watson FH, Burket JM. Painful tumors of the skin: "LEND AN EGG". J Am Acad Dermatol. Feb 1993; 28(2 Pt 2):298-300.
3. Han TY, Chang HS, Lee JH, Lee WM, Son SJ. A clinical and histopathological study of 122 cases of dermatofibroma (benign fibrous histiocytoma). Ann Dermatol. May 2011; 23(2):185-92.
4. Kubo M, Ihn H, Yamane K, Tamaki K. The expression levels and the differential expression of transforming growth factor-beta receptors in dermatofibroma and dermatofibrosarcoma protuberans. Br J Dermatol. May 2006; 154(5):919-25.
5. Plaszczyca A, Nilsson J, Magnusson L, Brosjö O, Larsson O, Vult von Steyern F, et al. Fusions involving protein kinase C and membrane-associated proteins in benign fibrous histiocytoma. Int J Biochem Cell Biol. Apr 8 2014.
6. Kaddu S, McMenamin ME, Fletcher CD. Atypical fibrous histiocytoma of the skin: clinicopathologic analysis of 59 cases with evidence of infrequent metastasis. Am J Surg Pathol. Jan 2002; 26(1):35-46.
7. Gleason BC, Fletcher CD. Deep "benign" fibrous histiocytoma: clinicopathologic analysis of 69 cases of a rare tumor indicating occasional metastatic potential. Am J Surg Pathol. Mar 2008; 32(3):354-62.
8. Ferrari A, Argenziano G, Buccini P, Cota C, Sperduti I, De Simone P. Typical and atypical dermoscopic presentations of dermatofibroma. J Eur Acad Dermatol Venereol. 2013; 27(11):1375-80
9. Bingham BA, Hatef DA, Chevez-Barrios P, Blackmon SH, Kim MP. Increased FDG activity in a dermatofibroma in esophageal cancer patient. Clin Nucl Med. 2013; 38(3):e140-2 
10. Krupa Shankar DS, Kushalappa AA, Suma KS, Pai SA. Multiple dermatofibromas on face treated with carbon dioxide laser. Indian J Dermatol Venereol Leprol. May-Jun 2007; 73(3):194-5.