Department of Otorhinolaryngology - Head and Neck Surgery, Ospedale Sant'Anna, Como, Italy.
Department of Otorhinolaryngology - Head and Neck Surgery, University of Insubria, Italy.
Am J Otolaryngol. 2022 Sep-Oct;43(5):103588. doi: 10.1016/j.amjoto.2022.103588. Epub 2022 Aug 6.
Solitary fibrous tumor (SFT) is a rare spindle-cell neoplasm [1]. Although typically originating from pleura, head and neck presentation accounts for about 6-18 % and very few cases have been described in paravertebral and posterior neck spaces [2]. Both computed tomography (CT) scans and magnetic resonance imaging (MRI) help in differential diagnosis of such lesion [3]. However, only histological and immunohistochemical studies give a conclusive diagnosis: CD34, BCL-2, and in particular STAT6 stainings are strongly orientative [4]. Radical surgery with free margin excision is the first treatment option, rarely requiring adjuvant therapy [2]. Prognosis is typically good and strictly related to histological risk assessment [5]. Rare cases of local recurrence and distant metastasis have been described in literature [2].
The purpose of this video is to describe the operative technique of a transcervical removal of a rare case of right paravertebral SFT. We present the diagnostic flowchart, management strategies, surgical technique and we provide anatomical dissection parallelism, which might be of interest to the readers.
A 59-years-old man with a one-year right cervical asymptomatic swelling was referred to our department. A contrasted MRI documented an expansive 6.5 cm capsulated lesion in the deep posterior neck spaces with diffuse contrast enhancement and inhomogeneous appearance. A core needle biopsy was performed, and the results from the initial immunohistochemical panel were not univocal showing positivity for cytokeratins AE1/AE3, PAX8, and no reactivity for CD34. A second immunohistochemical panel was then performed, displaying diffuse nuclear positivity for STAT6, which is a surrogate marker for the NAB2-STAT6 gene fusion, a specific driver mutation of SFT. Therefore, a radical excision was performed via transcervical approach (Video 1). No post-operative complications neither cranio-cervical neurological deficit occurred.
In comparison to pre-operative histopathologic study, the definitive histological examination of the whole mass revealed a more classical morphology of SFT. It was classified as an intermediate risk SFT [5]. A complete free margin excision was confirmed. After a multidisciplinary discussion, no adjuvant therapies were suggested. A six- and twelve-months radiological follow-up with MRI showed no evidence of disease.
SFT may represent a misdiagnosed entity in head and neck spaces and a correct diagnosis through immunohistochemistry is mandatory. Radical excision with free surgical margins should be pursued as adequate goal. Since SFTs show variable risk of metastatic disease, adjuvant radiotherapy should be contemplated in high-risk diseases and a clinico-radiological follow-up with MRI is required.
孤立性纤维瘤（SFT）是一种罕见的梭形细胞肿瘤[1]。尽管 SFT 通常起源于胸膜，但头颈部表现约占 6-18%，而非常少的病例发生于椎旁和颈后间隙[2]。计算机断层扫描（CT）和磁共振成像（MRI）有助于此类病变的鉴别诊断[3]。然而，只有组织学和免疫组织化学研究才能做出明确诊断：CD34、BCL-2，特别是 STAT6 染色具有很强的指向性[4]。根治性手术切除并保证切缘无肿瘤累及是首选治疗方法，很少需要辅助治疗[2]。预后通常较好，与组织学风险评估密切相关[5]。文献中也有局部复发和远处转移的罕见病例报道[2]。
本视频旨在描述一例罕见的右侧椎旁 SFT 经颈前路切除术的手术技术。我们提供了诊断流程图、管理策略、手术技术，并提供了解剖学平行性，这可能对读者有帮助。
一名 59 岁男性，1 年来右侧颈部无症状肿胀，来我院就诊。增强 MRI 显示颈后深部间隙有一 6.5cm 大小的包膜性扩张性病变，弥漫性强化，不均匀。进行了粗针穿刺活检，初始免疫组化结果不确定，显示细胞角蛋白 AE1/AE3、PAX8 阳性，CD34 阴性。然后进行了第二次免疫组化检测，显示 STAT6 弥漫性核阳性，STAT6 是 NAB2-STAT6 基因融合的替代标志物，是 SFT 的特定驱动突变。因此，我们采用经颈前路（视频 1）进行了根治性切除。患者术后无并发症，也无颅颈神经功能缺损。
与术前组织病理学研究相比，整块肿瘤的最终组织学检查显示出更经典的 SFT 形态。它被归类为中风险 SFT[5]。确认实现了广泛切缘无肿瘤累及。经多学科讨论后，未建议进行辅助治疗。6 个月和 12 个月的 MRI 影像学随访未见疾病证据。
SFT 可能是头颈部间隙中一种易误诊的疾病，通过免疫组化进行明确诊断是必要的。应追求广泛切缘无肿瘤累及的根治性切除。由于 SFT 转移疾病的风险不同，高危疾病应考虑辅助放疗，需要 MRI 进行临床影像学随访。
