16层螺旋CT对胰腺癌侵犯胰周血管可切除性判断标准的研究

目的：探索16层螺旋CT对胰腺癌侵犯胰周血管的可切除性评价的方法，试提出新的评判标准，分析该标准的敏感性、特异性及准确率。方法：搜集35例经病理证实的胰腺癌病例，行平扫及三期增强扫描，扫描后行CTA成像。术前根据胰周血管受累周径及长度拟定的新CT评判标准，采用1、2a、2b、3a、3b和4级共6个等级进行评判，并同手术结果对照。以不可切除作为阳性、可切除作为阴性，分别分析各等级敏感性和特异性，并绘制ROC曲线。比较以2级及2a级作为可切除性判断标准的差异，分析肿块不可切除的敏感性、特异性、阳性预测值、阴性预测值和准确率。结果：35例患者中，切除16例，另19例不可切除。与手术结果对照，以1级、2a、2b、3a和3b级作为可切除性判断标准，肿块不可切除的敏感性分别为80．1％、86．4％、69．5％、55．6％和45．2％。ROC曲线显示以2a级作为CT可切除性判断标准为最佳临界点。CT显示肠系膜上静脉出现“泪滴征”或胰周小静脉的扩张、侧支血管形成的共5例，其中仅有“泪滴征”1例能够切除。结论：新的CT评判标准对胰腺癌侵犯胰周血管的可切除性评价具有较高的临床应用价值，2a级可以作为CT可切除性判断标准为最佳临界点。

Pancreatic Carcinoma Invasion to Peripancreatic Vessels: The Criteria of Evaluation the Resectability with 16-detector-row-VCT

Objective:To evaluate newly introduced criteria for unresectability of pancreatic cancer with 16-detector-row-CT, and to analysis the sensitivity,specificity and accuracy of the new criteria.Methods:Thirty-five patients with pancreatic cancer underwent thin-section 16-detector-row-CT.The major peripancreatic vessels were categorized on a scale of 1,2a,2b,3a,3b and 4 grades,according to the degree of circumferential and the length involvement by tumor.The teardrop SMV,dilatation of peripancreatic veins and the compensatory circulation were also considered into the new criteria.Findings on CT were compared with the results of surgery in each patient.The sensitivity and specificity of each grade for vessels invasion were studied and receiver operator characteristic curve was obtained.The sensitivity,specificity,positive predictive value,negative predictive value and accuracy of unresectability for 2 degree and 2a degree were also calculated respectively.Results:Sixteen patients had surgically resectable tumors,and nineteen patients had surgically unresectable tumors.Compared with the findings of surgery, the sensitivity of unresectability was 80.1%,86.4%,69.5%,55.6% and 45.2%.Receiver operator characteristic curve demonstrated 2a degree was the optimal critical point.MSCT showed the teardrop SMV,dilatation of peripancreatic veins and the compensatory circulation in five patients;only one of these patients with the teardrop SMV had a surgically resectable tumor.Conclusion:The new criteria should be useful in predicting the respectability of pancreatic cancer.The degree of 2a was demonstrated as the optimal critical point by the ROC.