直肠癌直肠系膜浸润程度的术前螺旋CT与术后病理对照研究

目的 结合大组织切片技术,评价螺旋CT预测直肠癌直肠系膜浸润程度和环周切缘状态的价值.方法 对2007年3月至12月经纤维结肠镜及病理证实的直肠癌患者57例术前行64层螺旋CT增强扫描,预测直肠系膜浸润程度和环周切缘状态.全直肠系膜切除术后,利用大组织切片技术观察直肠系膜浸润程度和环周切缘状态,并与CT预测结果比较.计算螺旋CT预测直肠系膜浸润程度和环周切缘状态的准确率、敏感度、特异度、阳性预测值和阴性预测值.结果 肿瘤按直肠系膜浸润深度分级为Ⅰ度、Ⅱ度、Ⅲ度;螺旋CT预测系膜浸润程度总准确率为93.0%(53/57),其中Ⅰ度、Ⅱ度、Ⅲ度预测准确率分别为94.7%、94.7%、96.5%,与术后病理结果之间有较好的一致性(K=0.89,P<0.01).螺旋CT预测直肠癌环周切缘状态准确率93.0%(53/57),敏感度80.0%(12/15),特异度97.6%(41/42),阳性预测值92.3%(12/13),阴性预测值93.2%(41/44),与术后病理结果之间有较好的一致性(κ=0.76,P<0.05).结论 螺旋CT可准确预测直肠癌直肠系膜浸润程度和环周切缘状态.可作为术前影像学评估的常规手段.

Study on the tumor infiltration in mesorectum of rectal cancer by spiral computed tomography and histopathology

Objective To evaluate the value of spiral computed tomography in the preoperative assessment of the degree of tumor infiltration in mesoreetum and circumferential resection margin status of rectal cancer compared with large tissue shee technique. Methods Fifty-seven patients with rectal cancer diagnosed by fibercolonscopy and pathology from March 2007 to December 2007 underwent preoperative 64-layers spiral CT examination. The degree of tumor infiltration in mesorectum and circumferential resection margin status were evaluated. Large tissue slice technique was applied in the pathologic study after the total mesoreetal excision of the rectum to determine the degree of tumor infiltration in mesorectum and the circumferential resection margin status. The spiral CT findings were compared with pathologic results. The accuracy, sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) of the CT results were assessed respectively. Results The overall spiral CT accuracy was 93.0% (53/57) for the degree of tumor infiltration in mesorectum, and it was 94. 7%, 94. 7% and 96. 5% for degree Ⅰ,Ⅱ, Ⅲ infiltration, respectively. Fifty-three cases (93.0%) were accurately predicated with the circumferential resection margin status. The sensitivity, specificity, PPV and NPV of spiral CT measurement was 80. 0%, 97. 6%, 92. 3% and 93.2%, respectively, and was consistent well with the histopathological diagnosis. Conclusions Spiral CT provides accurate preoperative assessment for the degree of tumor infiltration in mesorectum and circumferential resection margin status of rectal cancer.