胸膜和胸膜外孤立性纤维性肿瘤临床病理分析

Pleural and extrapleural solitary fibrous tumor:clinical and pathological analysis

目的探讨胸膜和胸膜外孤立性纤维性肿瘤(solitary fibrous tumor,SFT)的临床病理学特点和鉴别诊断以及对预后的指导意义。方法采用光镜和免疫组织化学方法标志对6例胸膜SFT和8例胸膜外SFT进行分析。结果 14例(包括6例胸膜和8例胸膜外)SFT由比例不同的梭形和卵圆形肿瘤细胞组成,间质胶原纤维丰富伴有分支状血管。其中11例有典型的细胞稀少区和细胞丰富区交替分布特点,2例仅含细胞丰富区成分,1例为多发结节兼有上述两种形态特点。免疫组织化学染色结果显示14例肿瘤细胞均表达CD34、bcl-2和CD99,不表达desmin、S-100、EMA、CK(AE1/AE3)和p53。2例SMA呈部分弱阳性。SFT复发者2例,其中1例胸膜恶性SFT呈结节状播散性累及胸膜。结论胸膜和胸膜外孤立性纤维瘤在组织学形态、免疫表型和生物学行为上相似。免疫组织化学CD34、bcl-2和CD99表达阳性对SFT的诊断和鉴别诊断具有指导意义。

Objective To review the clinicopathological characteristics,differential diagnosis,treatment and prognosis of pleural and extrapleural solitary fibrous tumor（SFT） .Methods Tissue sections from 6 cases of pleural SFT and 8 cases of extrapleural SFT were examined by light microscopy and immunohistochemistry.Results Histologically,the lesions were composed of a varying admixture of spindle-shaped to round cells,variably collagenous stroma and branched hemangiopericytoma-like vessels.Eleven cases were characterized by alternating hypercellular and hypocellular areas,2 cases had moderate to high cellularity and little intervening fibrosis;1 case presented the combination of the two growth patterns with multiple masses.Immunohistochemically,all cases were positive for CD34,bcl-2 and CD99,and negative for desmin,S-100,EMA,CK（AE1/AE3） and p53.Two cases were focally and weakly positive for SMA.Two cases recurred,including 1 case of recurring malignant SFT with multiple masses attached to the visceral and parietal pleura.Conclusion Extrapleural SFT shares the clinical,pathologic and immunohistochemiacal features with pleural SFT.SFT shows a wide spectrum of histological features and has several variants.The tumor cells are diffusely or focally positive for CD34,bcl-2 and CD99,which may be of value for pathologic and differential diagnosis.