【作者】 赵晓俊；

【导师】 浦金贤；

【作者基本信息】 苏州大学 ， 外科学， 2010， 硕士

【摘要】 目的:通过分析小肾癌与肾错构瘤的多层螺旋CT表现,探讨使用多层螺旋CT鉴别小肾癌与肾错构瘤的方法,特别是探讨测量肿瘤大范围CT值的方法在鉴别小肾癌与肾错构瘤中的应用。方法:回顾性分析2006年3月至2009年6月在苏州大学附属第一医院治疗的93例肾脏小肿瘤(直径≤4cm)患者的CT图像,其中肾癌78例,肾错构瘤15例,均由术后病理证实。具体方法分为:1、分析肿瘤的多层螺旋CT表现特点,并在肿瘤的感兴趣点测量CT值,评价内容包括:①肿瘤的平扫密度;②肿瘤强化是否均匀;③肿瘤的强化程度;④肿瘤的强化形式;⑤肿瘤的边界;⑥肿瘤是否存在钙化;⑦肿瘤是否存在假包膜;同时包括病人的年龄和性别,并对结果进行统计学分析。2、分别于平扫期、皮质期、实质期测量整个肿瘤大范围的CT值,包括平均值、最大值、最小值及最大值与最小值之间的差;同时计算肿瘤的相对CT值。比较良恶性肿瘤组间各个指标的差异,并根据各个指标的受试者工作特征曲线(receive operating characteristic curve,ROC)下面积,分析诊断特异性与敏感性,得出有较高价值的鉴别良恶性肾肿瘤的指标。将得出的各个指标应用于2009年6月至2010年3月在苏州大学附属第一医院治疗的24例肾脏小肿瘤,手术前初步判断其良恶性,根据术后病理结果,进一步验证其实际应用价值。结果:1、肿瘤的平扫密度、强化形式、假包膜在鉴别小肾癌与肾错构瘤时具有统计学意义(P<0.05),其中,肾错构瘤的平扫密度低于肾癌(P=0.001);就强化形式而言,肾错构瘤多表现为延迟强化,而肾癌大多数表现为早期强化、快进快出的特点(P=0.001);肾癌部分存在假包膜,而肾错构瘤不存在假包膜(P=0.015)。肿瘤的强化程度、边界、钙化与否、强化是否均匀在鉴别肾脏小肿瘤的良恶性时均无统计学意义(P﹥0.05)。2、在肿瘤的感兴趣点测量CT值,仅平扫期CT值在小肾癌与肾错构瘤组间差异有统计学意义(P<0.05),其ROC曲线下面积仅为0.633;在整个肿瘤大范围测量CT值,其平扫期平均值、平扫期最小值、平扫期差值、皮质期最小值、实质期平均值、实质期最小值共6个指标在两组间差异均有统计学意义(P<0.05),每个指标的R0C曲线下面积均大于0.633;肿瘤的相对CT值在两组间差异均有统计学意义(P<0.05),R0C曲线下面积也均大于0.633。R0C曲线下面积前三位依次为平扫期肿瘤大范围最小CT值(0.849)、皮质期肿瘤大范围最小CT值(0.793)、实质期肿瘤大范围最小CT值(0.712)。当平扫期肿瘤大范围最小CT值≤-32Hu时,诊断肾错构瘤的敏感性与特异性最高,分别为76.7%、98.7%,将其作为最佳临界值判断另外24例肾脏肿瘤良恶性时,正确率最高,达83.3%。结论:对于CT上脂肪成分不明显的肾错构瘤,肿瘤的平扫密度、强化形式、是否存在假包膜是其与小肾癌鉴别的有价值的CT表现特点。CT值的增强幅度即肿瘤的强化程度在鉴别少脂肪错构瘤与肾癌时没有意义。在肿瘤大范围测量CT值的方法可以有效地提高小肾癌与肾错构瘤的诊断与鉴别水平,较传统的测量肿瘤感兴趣点CT值的方法具有更高的价值,其中肿瘤大范围最小CT值能够反映少脂肪肿瘤内部脂肪成分的存在。肿瘤大范围平扫期最小CT值为-32Hu可作为鉴别小肾癌与肾错构瘤的临界值。更多还原

【Abstract】 0bjective:To investigate the role of multi-slice computed tomography (MSCT) in the differential diagnosis of small renal cell carcinoma (RCC) and angiomyolipomas (AML).Methods:①.93 patients with small renal mass (≤4.0 cm) were retrospectively analyzed, 78 were RCC and 15 were AML by pathologic diagnosis through postoperative examination of specimen. Analyze the features of MSCT during unenhanced, corticomedullary phase (CMP) and early excretory phase (EP) scanning. CT number in ROI (region of interest) of these masses was recorded, CT number in ROW (region of whole mass)and Relative CT number of these masses was recorded at the same time, CT number in ROW includes the mean、maximum、minimum and the range between the maximum and minimum. CT features of RCC and AML were compared. Comparison between groups RCC and AML CT number, analyses the difference of each index in the area under the ROC.②. The diagnostic threshold for AML was applied to other 24 patients.Results:①.The results of comparison of AML and RCC in terms of tumor attenuation on unenhanced scans was valuable predictor for differentiating AML from RCC (P <0.05), High tumor attenuation was more common in cases of RCC than in cases of AML. Enhancement pattern was valuable predictor for differentiating AML from RCC (P <0.05), a prolonged enhancement pattern was observed in more than half (53%) of the patients with AML, whereas an early washout pattern was observed in most (59%) of the patients with RCC. Pseudocapsule was valuable predictor for differentiating AML from RCC too (P <0.05), none of the patients with AML had pseudocapsule, but 30% of the patients with RCC had pseudocapsule. CT number in ROI had difference between groups RCC and AML Only on unenhanced scans (P <0.05), 6 indexes of CT number in ROW and all of Relative CT number had difference between groups RCC and AML (P < 0.05).The area under ROC curve of CT number in ROI on unenhanced scans was 0.633, every area under ROC curve of 6 indexes of CT number in ROW and Relative CT number was beyond 0.633. Top3 of these indexes in descending order was Minimum in ROW on unenhanced scans (0.849), Minimum in ROW on CMP(0.793),Minimum in ROW on EP(0.712).When the most optimal diagnostic threshold for AML using Minimum in ROW on unenhanced scans≤-32Hu,its sensitivity was 76.7%、specificity was 98.7%; Minimum in ROW on CMP≤-22.5Hu, its sensitivity was 54.5%, specificity was 98%; Minimum in ROW on EP≤-7.5Hu, its sensitivity was 73.3%, specificity was 83.8%.②. The diagnostic threshold for AML (Minimum in ROW on unenhanced scans≤-32Hu) was applied to other 24 patients, the precision was 83.3%.Conclusions: MSCT may be useful in differentiating AML from RCC, with low tumor attenuation, prolonged enhancement pattern and no pseudocapsule being the most valuable CT findings. The way of measuring CT number of tumor in this study can effectively improve the sensitivity and specificity in diagnosing AML and small RCC. It may be a kind of new way in the differential diagnosis between AML and RCC, Minimum in ROW on unenhanced scans≤-32Hu may be accurate diagnostic threshold for AML. Further prospective work is needed before including this complicated counting system into practice.更多还原