胰腺中存在孤立纤维瘤（SFT）的报道越来越多，但仍然非常罕见。在此，我们首次报道了原发性胰腺SFT的一系列病例。分析了9例原发性胰腺SFT病例。平均年龄为60岁（36到76岁），无性别偏好。六例肿瘤位于头部，三例位于尾部。影像学研究显示，肿瘤被描述为高血管化的质地，有两例显示囊性区域，有三例被认为是神经内分泌肿瘤。活检结果显示，有两例被诊断为非典型的纺锤细胞肿瘤；一例误诊为可疑肉瘤，另一例误诊为转移性肾细胞癌。两例在冰冻切片上被诊断为低度恶性肉瘤和低度间质性肿瘤。肿瘤在外观上被分为界限清晰，中值大小为4厘米（0.9到15厘米）。显微镜下，肿瘤由卵圆形到纺锤形的肿瘤细胞组成，没有明显的有丝分裂活动，并按照细胞高与细胞低的区域交替排列。所有肿瘤中都检测到鹿角状血管和被困胰腺实质。在8例中，存在7例肿瘤细胞的核内STAT6表达弥漫/强阳性，9例中有7例CD34表达阳性，4例中有4例bcl-2表达阳性。一例检测到NAB2-STAT6融合。8名患者随访资料显示，平均随访时间为76个月（3到189个月），没有疾病复发。在胰腺间质性肿瘤的鉴别诊断中应考虑SFT的可能性。免疫组化核内STAT6表达是SFT的特征性特征。在我们的研究中，原发性胰腺SFT似乎具有良好的生物学行为。版权所有©2023 Wolters Kluwer Health，Inc.保留所有权利。

Solitary fibrous tumor (SFT) has been increasingly reported in various anatomic sites. However, it is still extremely rare in the pancreas. Herein, we present the first series of primary pancreatic SFTs. Nine cases of primary pancreatic SFTs were analyzed. The mean age was 60 years (36 to 76 y) with no sex predilection. Six tumors were in the head, 3 were in the tail. On imaging studies, tumors were described as a hypervascular mass, 2 revealed cystic areas, and 3 were favored to be neuroendocrine tumors. On biopsy, 2 cases were diagnosed as atypical spindle cell tumor; one was misdiagnosed as suspicious for sarcoma, and another case as metastatic renal cell carcinoma. Two were diagnosed as low-grade sarcoma and low-grade stromal tumor on frozen sections. Grossly, tumors were well-demarcated with a median size of 4 cm (0.9 to 15 cm). Microscopically, they were composed of ovoid to spindle tumor cells with no significant mitotic activity and were arranged in alternating hypercellular and hypocellular areas. Staghorn-like vessels and entrapped pancreatic parenchyma were also detected within all tumors. Tumor cells revealed diffuse/strong nuclear STAT6 expression in 7 of 8, CD34 in 7 of 9, and bcl-2 in 4 of 4 tested cases. One tested tumor harbored NAB2-STAT6 fusion. Eight patients with available follow-up data were free of disease at a mean follow-up of 76 months (3 to 189 mo). SFT should be considered in the differential diagnoses of mesenchymal neoplasms of the pancreas. Immunohistochemical nuclear STAT6 expression is a characteristic feature of SFT. Primary pancreatic SFTs seem to have favorable biological behavior in our series.Copyright © 2023 Wolters Kluwer Health, Inc. All rights reserved.