Keloid-like dermatofibroma

Abstract

Dermatofibroma is a common benign skin tumor, mainly occurring in young to middle-aged females. It is frequently localized in the lower extremities. A typical dermatofibroma usually presents itself as a single firm papule or nodule, of variable color, bluish, brownish, or pinkish. Its clinical, dermoscopic, and histological features usually allow easy diagnosis [1]. However, it is possible to observe some variations of these typical features. Keloid-like dermatofibroma is one of these atypical presentations rarely reported in the literature [2]. A 40-year-old patient with no previous medical history presented to our dermatology department with a lumbosacral lesion evolving for several months. A physical examination revealed a firm, well-demarcated, asymptomatic erythematous nodule, 5 × 12 mm in size, localized in the lumbosacral area (Fig. 1). The patient denied any trauma preceding the onset of the lesion. There was no personal or familial history of keloidal scars. A dermoscopic examination revealed erythema, telangiectatic vessels, a shiny white streak, and a brownish-yellow pigmentation (Fig. 2). A biopsy was performed. A histological examination revealed an atrophic epidermis. The dermis contained a fibroblastic proliferation of low cell density haphazardly arranged, located on a fibromatous background (Figs. 3 and 4). Dermatofibroma with a keloidal presentation was the diagnosis.