孤立纤维瘤是一种罕见的肿瘤，可影响身体的任何部位，包括头颈区域。其病因尚不清楚。男性发病率略高于女性，年龄范围为11至79岁。这是我国首例左侧腮腺孤立纤维瘤病例，通过局部腮腺切除并保存面神经进行了手术。组织学检查显示弥散性梭形细胞增生，适度的多形性，低有丝分裂指数（每10个高倍视野内<4个有丝分裂），部分被纤维囊膜包围。免疫组织化学显示STAT6、CD34、CD99阳性。六个月的随访未显示复发迹象。孤立纤维瘤是一种在软组织中广泛存在的间充质梭形细胞肿瘤，其头颈区域参与患者的占6％。其病因尚不清楚。可能的发病机制是NAB2-STAT6基因融合。它可以是无症状的，或症状与占位性肿块有关。诊断工作包括影像学、免疫组织化学和组织学。放射学检查结果可能导致对肿块的错误评估：相同的影像特征也出现在多形性腺瘤中，这是唾液腺最常见的肿瘤。本病例报告旨在强调，尽管罕见，但在慢性唾液腺肿块的鉴别诊断中应考虑孤立纤维瘤，因为可能需要更加侵袭性的治疗方法（如全腮腺切除、辅助放疗）。我们希望凸显多学科团队在确定最佳治疗方案时的作用，以针对患者量身定制治疗，并提高人们对这种罕见但有时具有侵袭性的肿瘤的认识。版权所有©2023作者。由Elsevier Ltd.出版。保留所有权利。

Solitary fibrous tumor is a rare neoplasm that can affect any part of the body, also head and neck region. Etiology is unknown. The incidence is slightly higher in males, the age ranges from 11 to 79 years.It's the first case in our country of left parotid solitary fibrous tumor, removed by partial parotidectomy with facial nerve preservation. Histology examination showed diffuse spindle-shaped cells proliferation, moderate polymorphism, low mitotic index (<4 mitoses per 10 HPF), partially bordered by fibrous capsule. Immunohistochemistry showed STAT6, CD34, CD99 positivity. Six-months follow-up didn't show sign of recurrence.Solitary fibrous tumor is a mesenchymal spindle cell neoplasm with fibroblastic differentiation ubiquitous in soft tissues, that involved the head and neck region in 6 % of cases. Etiology is unknown. The possible pathogenesis is NAB2-STAT6 gene fusion. It's asymptomatic or symptoms are related to space-occupying mass. Diagnostic work up involves imaging, immunohistochemistry, histology. Radiographic finding may lead to incorrect assessment of the mass: the same imaging features are present in pleomorphic adenoma, the most frequent tumor of salivary glands.This case report aims to stress that, although rare, solitary fibrous tumor should be considered in differential diagnosis in case of indolent salivary gland mass, since it may require more invasive approach (e.g., total parotidectomy, adjuvant radiotherapy). It would like to highlight the role of multidisciplinary team to define the best therapy, tailored for the patient, as well as to give awareness to a rare but sometimes aggressive tumor.Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.