INTRODUCTION
Dermatofibromas (DFs) are benign histiocytic fibrous nodules that arise in the skin and are more often seen on the legs and in women. They typically begin in young to middle age adults. Other names for DFs are histiocytoma, nodular subepidermal fibrosis, sclerosing hemangioma, fibroma durum, and fibroxanthoma.1 Clinically, dermatofibromas appear as firm nodules, varying in color from pink, purple, brown, or yellow. They may be single, or multiple, and range in size from 0.3 cm to 2.0 cm, but in our study were typically 0.6 cm. Many, but not all dermatofibromas will dimple in the skin with lateral pressure which can be used to assist in diagnosis. Dermatofibromas may be itchy, painful, unattractive, discolored, and have textural irregularities. Clinical diagnosis is usually simple, but occasionally biopsy is needed to distinguish them from carcinomas or melanocytic neoplasms. Pathologists have described dermatofibromas as having an increased number of fibrocytes in the dermis and subcutis,2 inflammatory cells including mostly macrophages and lymphocytes, coarse collagen bundles in haphazard array with peripheral entrapment,3 and hyperplasia of adjacent epidermis, hair follicles, and melanocytes.4 Zaballos et al studied the dermoscopic features of a series of 412 dermatofibromas. They reported that the most common dermoscopic pattern was a pigment network and a central white patch.5
The etiology of dermatofibromas is unknown, although they have been attributed to bug bites or trauma to the skin. There are recent reports of eruptive dermatofibromas arising in patients with a physiologic and immunologic change such as pregnancy or autoimmune diseases like lupus, myasthenia gravis, and pemphigus. There are other reports of multiple dermatofibromas arising in patients who are immunocompromised with hematologic malignancies, HIV, or in patients using medications such as methotrexate, antineoplastics, or biologics.6 Case reports of eruptive dermatofibromas following treatment with ustekinumab and efalizumab have been described.7 This association of eruptive dermatofibromas with such medications and in these systemic disease states has challenged any etiologic theory about dermatofibromas to include immunologic.
Prior to the use of lasers to treat dermatofibromas, dermatologists have typically treated symptomatic DFs with liquid nitrogen, intralesional triamcinolone acetonide injections, and excision; but all these options are considered less than ideal and pose significant risks for worsening the lesions with discoloration, scarring or atrophy. In addition, skin surgery wounds of the leg in adult women or men may be compromised in their healing due to circulation issues.
The etiology of dermatofibromas is unknown, although they have been attributed to bug bites or trauma to the skin. There are recent reports of eruptive dermatofibromas arising in patients with a physiologic and immunologic change such as pregnancy or autoimmune diseases like lupus, myasthenia gravis, and pemphigus. There are other reports of multiple dermatofibromas arising in patients who are immunocompromised with hematologic malignancies, HIV, or in patients using medications such as methotrexate, antineoplastics, or biologics.6 Case reports of eruptive dermatofibromas following treatment with ustekinumab and efalizumab have been described.7 This association of eruptive dermatofibromas with such medications and in these systemic disease states has challenged any etiologic theory about dermatofibromas to include immunologic.
Prior to the use of lasers to treat dermatofibromas, dermatologists have typically treated symptomatic DFs with liquid nitrogen, intralesional triamcinolone acetonide injections, and excision; but all these options are considered less than ideal and pose significant risks for worsening the lesions with discoloration, scarring or atrophy. In addition, skin surgery wounds of the leg in adult women or men may be compromised in their healing due to circulation issues.
