Atypical Presentation of Dermatofibroma: A Rare Case

Atypical Presentation of Dermatofibroma

Abstract

Background: Dermatofibroma, also termed benign fibrous histiocytoma, is a common benign fibrohistiocytic
tumor that typically presents as a firm reddish-brown nodule on the extremities. Atypical variants—particularly
atrophic and giant plaque-like forms occurring on the face—are exceedingly rare and may be mistaken for
inflammatory or malignant dermatoses. We report a 47-year-old woman who presented with a four-month
history of an 8 × 4 cm hyperpigmented, indurated, atrophic plaque on the right side of her face, without
antecedent trauma. Clinical differentials included morphea, lupus panniculitis, lichen sclerosus et atrophicus,
and subcutaneous sarcoidosis. Histopathology revealed dermal spindle cells in a storiform pattern with collagen
entrapment, and immunohistochemistry was positive for CD68 and ASMA and negative for CD34 and S100,
confirming dermatofibroma. The lesion was completely excised with cervicofacial flap reconstruction.
Recognition of such atypical facial variants is essential to guide accurate histopathological diagnosis.