多层螺旋CT检查在胃肠道间质瘤危险度分级中的应用

Clinical value of multislice spiral computed tomography examination on risk assessment of gastrointestinal stromal tumor

目的总结胃肠道间质瘤（GISTs）多层螺旋CT（MSCT）检查的特征，探讨不同级别危险度GISTs的MSCT检查征象与其危险度的关系。方法回顾性分析2011年7月至2014年2月天津医科大学肿瘤医院收治的110例GISTs患者临床病理资料。采用64排螺旋CT或16排螺旋CT进行扫描。扫描后将所有图像传人PACS工作站，进行薄层轴位、冠状位及矢状位等多平面重组分析。所有患者经手术取得肿瘤标本，通过对肿瘤标本的组织学形态观察和免疫组织化学染色检测进行病理学诊断，将极低、低及中等危险度问质瘤作为较低危险度，高危险度间质瘤作为高危险度。对于患者影像学特征和危险度情况进行分析，采用矿检验进行单因素分析，将有统计学意义的变量纳入多元Logistic回归模型进行多因素分析。结果肿瘤发生于胃8l例，小肠26例，结直肠3例；肿瘤直径为0．8～25．0cm，肿瘤较小者，多呈圆形或椭圆形，边界清楚，较大者形态多不规则，边界欠清晰；25例患者呈腔内型生长，35例患者呈腔内外型生长，50例呈腔外生长。增强扫描后105例患者肿瘤呈中度、明显强化；74例患者肿瘤呈不均匀强化；60例患者肿瘤内可见无强化低密度囊变坏死区；23例患者肿瘤表面可见浅表型、裂隙状或深大溃疡；钙化、转移和腹腔积液少见。根据不同危险度GISTs的MSCT检查表现，单因素分析结果显示：肿瘤部位、肿瘤直径、形态、边界、生长方式、强化方式、囊变坏死、溃疡及转移是影响肿瘤危险度分级的危险因素（χ^2=7．442，49．966，31．513，46．038，13．836，16．626，23．489，8．280，6．811，P〈0．05）；多因素分析结果显示：肿瘤直径〉10cm和溃疡是影响肿瘤危险度分级的独立危险因素（OR=9．927，0．070；95％可信区间：1．888～52．180，0．012—0．398，P〈0．05）。结论GISTs的肿瘤部位、肿瘤直径、形态、边界、生长方式、强化方式、囊变坏死、溃疡及转移等具有特征性，其中肿瘤直径〉10cm和溃疡是影响GISTs危险度分级的独立危险因素。

Objective To summarize the features of muhislice spiral computed tomography （MSCT） examination of gastrointestinal stromal tumors （ GISTs）, and investigate the relationship between predictors and risk of MSCT examination for GISTs. Methods The clinical data of 110 patients with GISTs who were admitted to the Tianjin Medical University Cancer Institute and Hospital from July 2011 to February 2014 were retrospectively ana- lyzed. All the patients received 64-slices spiral CT （64S-SCT） or 16-slices spiral CT （16S-SCT） scan, and the data were transported to the PACS work station for multiplanar reconstruction. All the tumor samples were collected during operation and diagnosed by morphological manifestation and immunohistochemistry of tumors. Very low, low, and medium risk of GISTs were regarded as lower risk grade, and high risk of GISTs as high risk grade. The univariate analysis and multivariate analysis about features of imaging and risk were done by chi-square test and multivariate logistic regression model. Results Tumors located at the stomach in 81 cases, small intestines in 26 cases and colorectum in 3 cases. Diameter of tumors was 0.8-25.0 cm. Smaller tumors were in round or oval shape with well demarcated boundary, and larger tumors were irregular with unclear boundary. Endo-luminal growth of Iessions was detected in 25 cases, duplex growth in 35 cases and extra-lunfinal growth in 50 cases. Enhanced CT scan showed that most of tumors in 105 patients demostrated moderate and high enhancement,heterogeneous enhancement in 74 cases, low density sacvariable necrosis area without enhancement in 60 cases and superficial, cracked-like and deep ulcer without calcification, metastasis and ascites in 23 cases. According to the features of GISTs by MSCT examination, location of tumor, diameter, shape, boundary, growth , enhancement, cystic necrosis, ulcer and metastasis were risk factors affecting risk classification of tumors by univariate analysis （χ^2=7.442, 49. 966, 31. 513, 46. 038, 13. 836, 16. 626, 23. 489, 8. 280, 6. 811, P 〈0.05）. Diameter of tumor more than 10 cm and ulcer were independent risk factors affecting risk classification of tumors by multivariate analysis （ OR = 9. 927, 0. 070 ; 95 % confidence interval： 1. 888-52. 180, 0. 012-0. 398, P 〈 0.05 ）. Conclusion There is a characterization in the location, diameter, shape, boundary of tumor, growth, enhancement, cystic necrosis, ulcer and metastasis, and diameter of tumor more than 10cm and ulcer are independent risk factors affecting the risk classification of GISTs.