CT测量直肠癌体积评估N分期的初步研究

Preliminary study of rectal carcinoma volume measured by CT for N staging assessment

目的探讨多层螺旋CT测量直肠癌体积评估N分期的价值。方法对168例经病理证实的直肠癌患者术前行64排螺旋CT腹盆腔增强扫描,在门脉期CT图像上测量直肠癌体积,分析测量结果和N分期的相关性,应用R OC曲线区分不同N分期的诊断效能。结果 CT测量肿瘤体积具有较好的一致性(Kappa值分别为0.74、0.81、0.63,P<0.05),与N分期呈正相关(r=0.643,P<0.05)。分析ROC曲线,区分N0与N1-N2组、N0-N1与N2组曲线下面积分别为0.75、0.88,体积阈值为13.43cm^3、21.52cm^3,敏感度53%、63%,特异度92%、91%。结论 CT测量直肠癌体积与N分期相关,对评估N分期有一定的应用价值,有利于指导临床选择个体化的治疗方案。

Objective To investigate the value of volume measured by multi-slice spiral CT for assessing N staging of rectal carcinoma. Methods 168 cases of rectal carcinoma proved by pathology were administrated 64-slice spiral enhanced CT examination in abdominal and pelvic two weeks before surgery. Volume of the tumor was calculated in the CT images of portal venous phase,and the correlation between the results and N staging was analyzed. ROC curve was used to distinguish the diagnostic value of different N staging. Results The tumor volume measured by CT had good consistency. Intra-observer Kappa value was 0. 74（P〈0. 05）,0. 81（ P〈0. 05）,Inter-observer Kappa value was 0. 63（ P〈0. 05）. The tumor volume was positively correlated with different N stages（ r = 0. 643,P〈0. 05）. ROC curve showed that the rectal carcinoma volume could help differentiate between stage N0 and stage N1-N2（ area 0. 75,cutoff 13. 43 cm^3,sensitivity 53%,specificity 92%）,stage N0-N1 and stage N2（ area 0. 88,cutoff 21. 52 cm^3,sensitivity 63%,specificity 91%） respectively. Conclusion The volume of rectal carcinoma measured by CT is correlated with N staging and plays an important part in evaluating lymph node metastasis and N staging,and it helps to optimize individualized clinical strategy for patients.