【摘要】 目的　探讨胃肠道间质瘤的组织起源和神经分化特征。方法　应用电镜和免疫组织化学对 2 0例胃肠道间质瘤的超微结构和神经分化相关抗原表达进行研究。结果　 2 0例胃肠道间质瘤c kit表达均阳性。其中 7例超微结构存在神经分化 ,12例未见神经或肌细胞分化 ,仅有 1例存在向平滑肌纤维分化。神经分化形态表现为瘤细胞胞质和胞质突起内可见散在或簇状分布的致密核心颗粒 ,并形成突触样结构。并可见神经元样突起、饮液空泡和团丝样纤维。神经分化伴有致密核心颗粒病例在良性、交界性和恶性组各有 1例、1例和 5例。神经分化组病例神经分化相关抗原神经元特异性烯醇化酶、CD99、S 10 0和CD5 6阳性表达分别有 7例、7例、5例和 4例 ,均高于未定分化组。结论　胃肠道间质瘤和所谓的胃肠道自主神经肿瘤在组织形态和免疫表型都存在相互重叠现象 ,神经分化超微结构观察和神经分化相关抗原分析有助于确定胃肠道间质瘤的神经分化改变以及潜在的生物学行为更多还原

【Abstract】 Objective To explore the histogenesis and neural differentiation of gastrointestinal stromal tumor(GIST). Methods The ultrastructural morphology and neural differentiated antigen expression were studied in 20 cases of GIST using electron microscopy and immunohistochemistry. Results All of the 20 cases mentioned were positive for c kit expression. The ultrastructural features of neural differentiation were observed in 7 cases, while no neural or myogenic differentiation seen in 12 cases. Myogenic differentiation to smooth muscle was observed in one case. The ultrastructural features of neural differentiation included scattered or cluster distribution of dense core granules in cytoplasm and cytoplasmic processes; formation of synaptic construction of cell processes; and neurogenic like processes. In some cases pinocytotic vesicles under the cell membrane and skenoid fibers were seen. Neural differentiation with dense core granules was seen in one case in benign, one case in borderline and five cases in malignant group. The positive reactivity of neural differentiated antigen NSE, CD99, S 100p and CD56 in cases of the neural differentiation group appeared in seven, seven, five and four cases respectively, which were significantly higher than that of the undifferentiated group. Conclusions It′s rather difficult to differentiate GIST accompanying with neural differentiation from gastrointestinal autonomic nerve tumor if depending only on its histology and immunophenotype appearance, since many features were overlapping in both tumors. Examination of the neural ultrastructures and neural differentiated antigen in GIST might be helpful to clarify the neural differentiation and potential behavior of GIST.更多还原