多层螺旋CT对胰腺癌转移淋巴结的诊断能力初步分析

Reliability of multi-slice helical CT in diagnosis of nodal involvement in patients with pancreatic adenocarcinoma

目的:分析多层螺旋CT对胰腺癌转移淋巴结的诊断能力。方法:自2005年11月～2007年3月对87例临床疑诊为胰腺肿瘤的患者行多层螺旋CT薄层扫描,根据三维重建影像学结果确定腹部淋巴结肿大情况;17例行胰腺肿瘤根治手术,其中13例确诊为胰腺腺癌;切除标本由病理科医师确定淋巴结位置及是否转移,将影像学数据与病理结果对照分析。结果:按照外形特征及淋巴结位置,CT图像中共有41枚淋巴结可与病理结果对应,其中16枚(39.0%)转移阳性,短轴直径与非转移组淋巴结比较无统计意义(P=0.27)。分别以淋巴结短轴直径大于3mm、10mm及淋巴结长短轴直径比小于2为淋巴结转移阳性诊断标准,敏感度分别为93.8%、18.8%及50%,特异度分别为40%、88%及72%,阳性预测值分别为38.5%、50%及53.3%,阴性预测值分别为50%、62.9%及69.2%,准确度分别为39%、61%及63.4%。结论:使用多层螺旋CT以适当标准判断胰腺癌淋巴结有无转移,可以获得较高的敏感度或特异度,为选择恰当的治疗方案提供依据。

Objeetive：To identify the reliability of multi-slice helical CT in diagnosis of nodal involvement in patient with pancreatic adeno-eareinoma. Methods： Eighty-seven patients with suspected pancreatic tumor received a multi-slice helical CT preoperative scan from 2005 November to 2007 March, and 3-dimeusion CT images were interpreted in consensus by two radiologists. Seventeen patients reeeived radical resection and thirteen were identified as adeno-careinoma ultimately. The location and histological diagnosis of lymph nodes were also identified by pathologists, the CT image data of lymph nodes were compared with pathological results. Results： Totally, 41 lymph nodes in the CT image can be found eon＇espanding to the pathology based on the shape and location of the node, in which 16 （39.0%） were metastatic ones. The short-axis diameter of lymph nodes showed no statistic difference between metastatic and nonmetastatic ones （ P = 0.27）. Using different diagnostic threshold including short-axis diameter greater than 3 mm or 10 mm, the ratio of long-axis and short-axis diameter 〈 2, as the eriterions for nodal involvement, we found the sensitivity of 93.8%, 18.8% and 50% respectively, specificity of 40%, 88% and 72%, with positive predictive value of 38.5%, 50% and 53.3%, negative predictive value of 50%, 62.9 % and 69.2 %, overall accuracy of 39 %, 61% and 63.4 %. Conclusion： Using multi-slice helical CT to identify lymph nodal involvement of patients with pancreatic adenocarcinoma with certain criterion, high sensitivity or specificity would be achieved. Different criterions of high sensitivity or high specificity should be applied to different lymph nodes which had different clinical significance.