Epithelioid sarcoma arising from the temporal space: A case report

INTRODUCTION: Epithelioid sarcoma is a malignant soft tissue tumor arising from mesenchymal tissue and usually occurs in the extremities. The tumor involving the head and neck region is extremely rare. We present radiologically well-documented case of an epithelioid sarcoma arising from the temporal space. CASE PRESENTATION: A 35-year-old woman presented with a slowly growing, painless palpable mass in the left temporal area. Ultrasound (US) revealed a lobulated hypoechoic mass with internal vascularity. On magnetic resonance (MR) imaging, the mass showed heterogeneous signal intensity with a central necrotic area and peritumoral infiltration. On the basis of the clinical and radiological characteristics, the lesion was considered to be a malignant tumor originating from soft tissue. An incisional biopsy was performed. The diagnosis of epithelioid sarcoma was based on microscopic examination and immunohistochemical analysis. (18)F-fluorodeoxyglucose positron emission tomography/computed tomography ((18)FDG-PET/CT) was used to stage the tumor and demonstrated intense FDG uptake in the mass without regional lymph node or distant metastasis. After the pathologic diagnosis of epithelioid sarcoma, the patient underwent total surgical resection of the tumor followed by postoperative irradiation. There was no evidence of recurrent disease during the follow-up period of 18 months. CONCLUSION: An epithelioid sarcoma should be considered in the differential diagnosis of a locally aggressive lesion occurring in the temporal space of head and exhibiting a heterogeneous appearance on imaging studies, including a central necrotic area and signal intensity suggestive of infiltration of soft tissue adjacent to the tumor. It is, however, true that head-and-neck involvement is very rare, and the radiological findings are not pathognomonic.