Nodular Fasciitis of the Face Following an Insect Bite: A Case Report

Nodular fasciitis (NF) is a rare, benign proliferation of fibroblasts that can mimic soft tissue sarcomas. It most commonly occurs in the upper extremities and trunk, while head and neck involvement in adults is uncommon. We report a case of a 50-year-old female presenting with a progressively enlarging right temporal lesion following an insect bite. Imaging revealed a well-circumscribed, low- to iso-dense lesion based in the temporal fascia with mild fluorodeoxyglucose (FDG) uptake on positron emission tomography-computed tomography (PET-CT), consistent with benign pathology. Histopathological examination demonstrated spindle-shaped myofibroblasts with a mixed inflammatory infiltrate and no evidence of malignancy. Immunohistochemistry was positive for Actin, supporting the diagnosis of NF. The lesion regressed spontaneously following corticosteroid therapy. This case highlights an unusual presentation of NF in the temporal region of an adult. Awareness of its clinical and radiologic features is essential to avoid misdiagnosis and unnecessary aggressive management.