肺及纵隔原始神经外胚层肿瘤的临床病理学特点

Clinicopathological features of primitive neuroectodermal tumors of the lung and mediastinum

目的探讨肺原始神经外胚层肿瘤(PNET)的病理学特征。方法收集郑州大学第一附属医院2012年4月至2018年7月间7例诊断为肺、纵隔原始神经外胚层肿瘤的病例,采取常规HE染色,免疫组化检测及荧光原位杂交检测,总结其临床病理学、免疫组织化学及相关基因的特点,提高对此疾病的认识。结果7例病例中,男性6例,女性1例,年龄3~34岁,中位年龄14岁。左肺及纵隔2例,右肺5例。肿块大小5.7~15.9cm,中位数9.7cm。光镜下观肿瘤细胞为形态较一致的小圆形细胞,呈弥漫或被血管纤维组织分隔为巢状、梁状分布,胞质较少,核椭圆形或短梭形,可见菊形团结构,核分裂像易见,可有坏死。免疫组化示:肿瘤细胞表达CD99、Fli-1、Syn、Vimentin、CD56,而不表达CK(AE1/AE3)、TTF-1、EMA、LCA。荧光原位杂交法检测EWSR1基因均发生断裂。结论原始神经外胚层肿瘤是主要发生于青少年的罕见小圆细胞恶性肿瘤,免疫组织化学染色及EWSR1基因检测对其诊断有重要作用。

Objective To investigate the pathological features of primitive neuroectodermal tumors of the lung. Methods Seven cases of primitive neuroectodermal tumors of the lung and mediastinum diagnosed in the First Affiliated Hospital of Zhengzhou University from April 2012 to July 2018 were collected. Routine HE staining, immunohistochemical detection and fluorescence in situ hybridization were used to summarize the characteristics of clinicalpathology, immunohistochemistry and related genes, to improve the understanding of the disease. Results Among the 7 cases, 6 were males and 1 female, aged 3 to 34 years, with media age of 14 years. There were 2 cases of left lung and mediastinum and 5 cases of right lung. The size of the mass ranged from 5.7 cm to 15.9 cm, with media size of 9.7 cm. Under light microscopy, the tumor cells were small round cells with similar morphology, diffuse or separated by vascular fibrous tissues into nest-like and beam-like distribution, with less cytoplasm, oval or short fusiform nucleus, chrysanthemum-like structure could be seen, mitotic image could be seen easily, and necrosis may occur. Immunohistochemistry showed that the tumor cells expressed CD99, Fli-1, Syn, Vimentin, CD56, but CK (AE1/AE3),TTF-1, EMA and LCA were negtive. Fluorescence in situ hybridization detected the breakage of EWSR1 gene. Conclusion Primitive neuroectodermal tumors is a rare small round cell malignant tumor mainly occurring in adolescents. Immunohistochemical staining and EWSR1 gene detection play an important role in its diagnosis.