Histiocytoma (synonyms: Dermatofibroma lenticulare, nodulus cutaneus; ICD-10-GM D23.9: Other benign neoplasms of the skin: skin, unspecified) are benign (benign) reactive fibroblasts (principal cells of connective tissue) that resemble hard fibroma. It is also called dermatofibroma.
Age of manifestation (first age of onset of disease): adults in the 3rd-6th decade of life; less commonly, children.
Sex ratio: women more often than men
The prevalence (disease incidence) for histocytomas is more than 60% of patients in larger dermatologic collectives.
Symptoms – Complaints
They are tight and painless papules (nodules; or nodules/nodules) measuring a maximum of 0.3-1.5 cm in size and occurring singly or multiply (multiple). They may be brownish to bluish due to hemosiderin (dye) deposition, reddish or yellowish due to fat deposition.
This skin change occurs mostly on the extremities.
Differential diagnoses
- Angiohistiocytoma with giant cells;
- Disseminated connective tissue nevus.
- Cutaneous mastocytoma – mast cell accumulations in a large thick patch.
- Cutaneous myofibroma
- Leiomyoma – benign tumor of smooth muscle.
- Malignant melanoma (black skin cancer).
- Perineurioma – benign tumor of the nerves.
- Rheumatoid nodule (rheumatoid nodule) – subcutaneous (located under the skin), coarse, shifting nodules that form in front of all pressured areas.
- Schwannoma – benign and usually slow-growing tumor of the peripheral nervous system, which originates from the Schwann cells.
- Xanthogranuloma juvenile
- Xanthoma – harmless, shimmering orange-yellowish, nodular to plaque-like fatty deposits in the skin.
Pathogenesis (disease development) – etiology (causes)
The cause of a histiocytoma is usually inflammation resulting from a small injury to the skin (for example, after an insect bite).
Therapy
Histiocytomas can be removed surgically or by CO2 laser.
