Abstract
Benign fibrous histiocytoma (FH) is a benign neoplasm of a mixture of fibroblastic and histiocytic cells. The tumor occurs most frequently on the skin of the extremities but rarely in deep soft tissues of the head and neck. The diagnosis of benign FH may be clinically difficult, and is frequently confirmed after excision. The most important diagnostic distinction is the separation of this tumor from malignant FH. A 22-year-old male presented with a painless swelling mass on the left cheek. Detailed clinical and laboratory examinations were performed. The patient received angiography with embolization and underwent an intraoral excision of the mass under general anesthesia with primary closure. The histopathology revealed a benign FH. The complete image survey and appropriate treatment of benign FH of the cheek are emphasized.
1
Introduction
Benign FH represents a diverse group of neoplasms which exhibit both fibroblastic and histiocytic differentiation. The cell of origin is believed to be the histiocyte, but the varied microscope appearances of the lesion have led to the use of numerous alternative diagnostic terms, including dermatofibroma, sclerosing hemangioma, xanthogranuloma, fibroxanthoma, and nodular subepidermal fibrosis.
This tumor most frequently occurs in the dermis of the extremities, but is also sporadically found in soft tissue and parenchymal organs. The benign FH usually originates in sun-exposed skin but has rarely been reported in deep soft tissues of the head and neck. We report an unusual case of benign FH of the cheek in a young patient and show the related clinical features, complete image study, pathological characteristics and appropriate management.
2
Case report
A 22-year-old male presented at our ENT outpatient clinic, with an apparently painless swelling on his left cheek, which had been present for approximately one year. His medical history was noncontributory. Physical examination revealed a well-circumscribed, moderately mobile, non-tender fibroelastic mass of approximately 3 cm in diameter ( Fig. 1 ). The mucosal surface appeared smooth and intact. Color duplex echography of the tumor revealed a well-defined mass with feeding artery about 3.32 × 3.11 cm in size ( Fig. 2 .1). The T2-weighted magnetic resonance imaging sequence showed a well-demarcated mass with high-level signal intensity over the left buccal space ( Fig. 2 .2). Angiography showed the feeding artery from facial artery and embolization was performed ( Fig. 2 .3). The buccal mass decreased in size after embolization and was mobile better. The patient underwent intraoral excision of the mass under general anesthesia with primary closure. Dissection of the tumor from the surrounding tissues was relatively easy with minimal bleeding and complete surgical excision of the mass was performed smoothly.
Histologic analysis of the specimen revealed a macroscopically smooth, well-circumscribed encapsulated lesion of 3.3 × 2.8 cm in dimension. The mass was grossly oval-shaped in appearance ( Fig. 3 ). Microscopically the tumor was composed of fibroblast-like spindle cells with fascicular and focally storiform arrangement ( Fig. 4 ). There were no mitotic figures, cellular pleomorphism, multinuclear giant cells, nuclear atypia or necrosis. The stroma was collagenised and demonstrated a rich vascularity. There was a scattered inflammatory infiltrate predominantly composed of lymphocytes and plasma cells. The tumor cells showed strong immunoreactivity for vimentin, weak and focal immunoreactivity for CD34. There was negativity for desmin, alpha smooth muscle actin (α-SMA), S-100 protein. The final diagnosis was benign FH. The patient was free of locoregional disease after 10-months of follow-up.
