咽部淋巴结外滤泡树突细胞肉瘤诊治分析

Study on Diagnosis and Treatment of Pharyngeal Extranodal Follicular Dendritic Cell Sarcoma

目的:探讨咽部淋巴结外滤泡树突细胞肉瘤(Follicular dendritic cell sarcoma,FDCS)的临床病理特点、生物学行为及诊断与治疗要点。方法:对1例咽部结外FDCS进行临床病理观察、免疫组织化学及原位杂交检测,并结合文献进行分析。结果:肿瘤组织位于咽部粘膜下,呈巢团状、片状排列,瘤组织间见多少不一的淋巴细胞浸润;免疫组化显示瘤细胞CD21、CD35、CXCL-13弥漫阳性,CD23、Podoplanin(D2-40)灶性阳性;EBER原位杂交阴性。结合文献分析发现咽部结外FDCS多发生于中青年,无明显性别差异。大多数肿瘤病变比较局限,体积相对较小,可能属于一类低度恶性肿瘤。由于对其认识不足,常常疏于考虑而误诊。据现有病例资料推荐采用根治性手术切除,目前尚没有证据支持术后的辅助放化疗可以改善预后。结论:咽部结外FDCS是一种罕见且容易误诊的低度恶性肿瘤,加深临床及病理医师对该肿瘤的认识有助于减少误诊。

Objective： To investigate the clinicopathologic features,biologic behavior,and key points of diagnosis and treatment of pharyngeal extranodal follicular dendritic cell sarcoma（FDCS）.Methods： A case of pharyngeal extranodal FDCS was studied by light microscopy,immunohistochemistry and in situ hybridization,and the relevant literatures were reviewed.Results： The tumor was located beneath the stratified squamous epithelium of parapharyngeal space,and had a nested or diffuse growth pattern,sprinkled with small lymphocytes.Immunohistochemical stain for CD21,CD35,CXCL-13 were intensely positive and for CD23,for podoplanin（D2-40） it was focal positive,while EBV-encoded RNA by in situ hybridization were negative.The tumor tended to affect young to middle-aged adults without a sex difference.The tumors were generally localized when they were found or diagnosed and are usually smaller than 5 cm in greatest dimension,regarded as a low-grade sarcoma.It was often not considered at the initial evaluation and might be misdiagnosed as other tumors.Radical surgery was recommended,but no evidence to support postoperative adjuvant therapy.Conclusions： Pharyngeal extranodal FDCS was a rare low-grade malignancy that is often misdiagnosed.Increased awareness of the existence of FDCS may help to reduce the potential for diagnostic error.