高场MRI对胃肠间质瘤的诊断

目的 分析高场MRI对胃肠间质瘤(GIST)影像表现,探讨其对该肿瘤的诊断价值.方法 对经病理证实的45例GIST的高场磁共振影像学资料进行回顾分析.结果 45例GIST中,发生于骶前2例,会阴部5例,小肠5例,直肠10例,胃内23例.其中有11例为术后复发,余34例为新发.高场MRI表现为不均匀的肿块信号影,体积小者信号均匀,体积大者信号不均匀,可出现囊变、坏死、出血等;增强后肿块实性部分异常强化信号影,坏死、囊变区无明显强化信号影.肿瘤边界清晰或不清晰,邻近组织受压,易发生转移或腹腔内种植.病理结果显示: 肿瘤大体,切面呈灰白、灰红色,可见包膜.镜下主要由形态多样、数量不等的梭形细胞构成.免疫组化CD34(+)为43例;CD117(+)为40例;Desmin(+)为18例;Vimentin(+)为15例.结论 高场MRI对GIST可以准确定位,对其诊断及鉴别诊断具有重要价值.

High-field MRI for diagnosis of gastrointestinal stromal tumor

Objective To study the high-field MRI findings of gastrointestinal stromal tumors(GIST), investigate the diagnostic value of the tumor.Methods The image findings and clinical date of 45 cases with GIST proved by pathology were analyzed retrospectively.Results In 45 cases of GIST,tumors were located in the sacroanterior 2 cases, in the perineum 5 cases, in the small bowel 5 cases, in the rectum 10 cases and in the stomach 23 cases.Of 45 cases, there were 11 cases of recurrence,and 34 cases of new-onset.High-field MRI showed the tumors with inhomogeneous signal intensity, the small lesions with even homogeneous signals, the larger with non-uniform signalwhich may be cystic degeneration, necrosis, hemorrhage.After enhanced scan,the solid part of the tumor were abnormal enhancement,necrosis andcystic degeneration no enhancement.Clear or not clear of tumor boundaries andadjacent tissue pressure were prone to metastasis or intraperitoneal planting.Pathology results showed: the tumors cut surface was gray, gray-red, visible envelope.The microscopic morphology was varied, ranging from the number of spindle cells.Immunohistochemical findings were as following: CD34(+) in 43 cases;CD117(+) in 40 cases;Desmin(+) in 18 cases;Vimentin(+) in 15 cases.Conclusion High-field MRI can accurately position gastrointestinal stromal tumor, and has great value for its diagnosis and differential diagnosis.