吻合血管瘤是具有吻合血管通道的良性肿瘤，可能类似于血管肉瘤。虽然吻合血管瘤在不同部位都有描述，特别是腹部/脊柱旁区域，但纵隔吻合血管瘤的数据仍然有限。我们报告了最大的单机构纵隔吻合血管瘤系列的临床病理学、放射学和分子特征。在我们 2011-23 年的病理档案中，我们回顾了所有涉及纵隔的血管病变，并确定了 7 个吻合血管瘤。临床信息是从病历中提取的；审查了现有的放射成像。对 5 例进行了基于 DNA 的靶向二代测序（447 个基因，包括 GNAQ 和 GNA11）。这 7 名患者包括 5 名女性和 2 名男性，年龄范围为 55-77（中位数 = 72）岁。在可用放射学检查的六个肿瘤中，各有两个位于血管前纵隔、内脏纵隔和椎旁纵隔，所有经过对比增强检查的肿瘤均具有分叶状外周强化。六名患者接受了肿瘤切除术；一名患者接受了质子放射治疗。在显微镜下，每个肿瘤都是孤立的，其特征是有吻合的毛细血管大小的血管，内衬平头钉内皮细胞。纤维蛋白微血栓、透明球和髓外造血很常见。在通过新一代测序分析的 5 个肿瘤中，在一个肿瘤中鉴定出了 GNAQ p.Q209P；其余案件中没有发现其他可报告的变更。切除后随访 3-58（中位=9.5）个月，四名患者未发现复发。虽然纵隔吻合血管瘤在显微镜下可以模仿血管肉瘤，但对该实体的认识和放射学相关性可能有助于规避这一诊断陷阱。 © 2023 约翰·威利

Anastomosing haemangiomas are benign tumours with anastomosing vascular channels that may mimic angiosarcoma. While anastomosing haemangiomas have been described in diverse locations, particularly the abdominal/paraspinal region, data on anastomosing haemangiomas in the mediastinum remain limited. We report the clinicopathological, radiological and molecular characteristics of the largest single-institutional series of mediastinal anastomosing haemangiomas.In our pathology archives in 2011-23, we reviewed all vascular lesions involving the mediastinum and identified seven anastomosing haemangiomas. Clinical information was abstracted from medical charts; available radiological imaging was reviewed. Targeted DNA-based next-generation sequencing (447 genes, including GNAQ and GNA11) was performed on five cases. The seven patients included five women and two men, with an age range of 55-77 (median = 72) years. Of the six tumours with available radiology, two each were in the prevascular, visceral and paravertebral mediastinum, with lobulated peripheral enhancement in all tumours examined with contrast enhancement. Six patients underwent tumour resection; one patient received proton radiotherapy. Microscopically, each tumour was solitary and characterised by anastomosing capillary-sized vessels lined by hobnail endothelial cells. Fibrin microthrombi, hyaline globules and extramedullary haematopoiesis were common. In the five tumours analysed by next-generation sequencing, GNAQ p.Q209P was identified in one tumour; no additional reportable alterations were identified in the remaining cases. No recurrence was noted in the four patients with available follow-up of 3-58 (median = 9.5) months after resection.While mediastinal anastomosing haemangiomas can microscopically mimic angiosarcoma, awareness of this entity and radiological correlation may help to circumvent this diagnostic pitfall.© 2023 John Wiley & Sons Ltd.