摘要目的 探讨滤泡树突细胞肉瘤(FDC肉瘤)的临床病理特征及其鉴别诊断.方法 对10例FDC肉瘤行HE染色、免疫组织化学EnVision法染色,对其中5例进行原位杂交,并对7例进行了随访.结果 10例患者中男5例,女5例,平均年龄42岁.发生于结内的6例,主要位于颈部和腹膜后淋巴结;发生于结外的4例,分别位于扁桃体、盆腔、胰尾部和脾脏.镜下观察瘤细胞呈旋涡状、席纹状或片块状排列.肿瘤细胞呈合体状、胖梭形或上皮样,胞质红染,边界不清,细胞核圆形或卵圆形,空泡状,核仁清楚,核分裂象多少不等.偶见核内假包涵体及多核瘤巨细胞.小淋巴细胞或中性粒细胞夹杂于瘤细胞间或围绕血管周围.瘤细胞CD21、CD23、CD35及D2-40呈弥漫或灶状阳性,少数病例瘤细胞上皮细胞膜抗原、CD68、S-100蛋白阳性,白细胞共同抗原、CD20、CD3、CD1a、HMB45、细胞角蛋白均阴性.EBER原位杂交,1例炎性假瘤样FDC肉瘤阳性,另外4例经典型FDC肉瘤为阴性.随访7例,随访2～39个月(平均14个月).2例伴有副肿瘤性天疱疮的患者分别于确诊半年和7个月后死于肺部感染,其余5例经手术切除或辅以放疗和化疗后,无复发和转移.结论 FDC肉瘤是一种少见类型的低至中度恶性肿瘤.CD21、CD35及D2-40的应用有助于其正确的诊断和鉴别诊断.多数病例局部手术切除或辅以放疗和化疗,预后较好,伴有副肿瘤性天疱疮的患者预后差.

abstractsObjective To study the clinicopathologic features of follicular dendritic cell sarcoma(FDCS) and its differential diagnosis. Methods Ten cases of FDCS were studied by light microscopy,immunohistochemistry and in-situ hybridization. The clinical features and follow-up information were of the patients was 42 years. Six of them were located in cervical and peritoneal lymph nodes and four in extranodal sites (including tonsil, pelvic cavity, tail of pancreas and spleen). Histologically, the tumor cells had whorled, storiform or diffuse growth patterns. They were spindle in shape and contained syncytial eosinophilic cytoplasm, with round or oval nuclei, vesicular chromatin, distinct nucleoli and a variable number of mitotic figures. Multinucleated tumor giant cells and intranuclear pseudoinclusions were occasionally seen. There was a sprinkling of small lymphocytes and neutrophils within the tumor as well as in the perivascular region. Immunohistochemical study showed that the tumor cells were diffusely or focally positive for CD21, CD23, CD35 and D2-40, but negative for LCA, CD20, CD3, CD1a, HMB45 and CK.Some of them showed EMA, CD68 and S-100 reactivity. In-situ hybridization for Epstein-Barr virus-encoded RNA (EBER) showed positive signals in only one case (which was diagnosed as inflammatory pseudotumor-like FDCS). Of the 7 patients with follow-up information available (duration: 2 months to 39 months; mean: 14 months), 2 cases with paraneoplastic pemphigus died of pulmonary infection at 5 and 7 months respectively. The remaining 5 patients were alive and disease-free after surgical excision ( +/-chemotherapy and radiotherapy). Conclusions FDCS is a rare low to intermediate-grade malignant tumor. Appropriate application of FDC markers, such as CD21, CD35 and D2-40, would be helpful for arriving at a correct diagnosis. Most cases are associated with good prognosis after surgical treatment, with or without chemotherapy and radiotherapy. Patients with paraneoplastic pemphigus carry a less favorable prognosis.