磁共振与多层螺旋CT在胃癌术前分期中的诊断价值

目的利用磁共振(MRI)与多层螺旋CT(MSCT)前瞻性地对胃癌进行术前TNM分期并与病理结果对照,确定其在胃癌术前分期中的作用。方法对经活检证实的48例胃癌患者行MRI和MSCT比较研究。结果MRI对T分期的判断准确率为91.6%,MSCT为72.9%;MRI鉴别T2和T3期胃癌的准确率为90.1%,MSCT为69.8%。MRI对T分期与MSCT在各期上的比较除鉴别T2和T3期胃癌有显著统计学差异外(P<0.05),其他均无统计学差异(P>0.05)。MRI对胃癌术前N分期的判断敏感性、特异性和准确性为62.8%、69.2%和64.5%,MSCT为82.8%、76.9%和81.4%,其中准确性分别为N069.2%(9/13)和77.0%(10/13);N165.1%(15/23)和82.8%(19/23);N258.3%(7/12)和83.3%(10/12);对N分期的总体判断上有显著性差异(P<0.05)。MRI对胃癌M分期的判断准确率及对远处转移的敏感性和特异性分别为90.6%、75.0%和92.5%,与MSCT相同;两者对术前TNM分期的判断准确率分别为75.0%和79.2%,其中对早期胃癌的准确率分别为83.3%和66.7%,对进展期胃癌准确率为73.3%和70.8%,两者比较无统计学差异(P>0.05)。结论与MSCT相比较,MRI动态增强加脂肪抑制以及延迟扫描对于早期病变的显示,区分T2和T3、T3和T4都有其潜在的优势,对T分期诊断的准确性也高于MSCT。

Diagnostic value of MRI and MSCT in preoperative TNM staging of gastric cancer

Objective To investigate the value of multislice CT(MSCT)and magnetic resonance imaging(MRI)in the preoperative TNM staging of gastric cancer.Methods Both MRI and MSCT were performed in 48 cases with gastric cancer confirmed by biopsy.Results The accuracy for T staging detected with MRI and MSCT were 91.6% and 72.9%,respectively(P>0.05,except T2 and T3 staging),and for T2 and T3 90.1%(MRI)and 69.8%(MSCT)(P<0.05).The accuracy for N staging were 64.5% for MRI,81.4% for MSCT,with N0 69.2%(9/13)and 77.0%(10/13),N1 65.1%(15/23)and 82.8%(19/23),and N2 58.3%(7/12)and 83.3%(10/12).The sensitivity for N staging were 62.8%(MRI)and 82.8%(MSCT),and specificity 69.2%(MRI)and 76.9%(MSCT).There was significant difference in the overall accuracy for N staging between MRI and MSCT(P<0.05).The accuracy for M staging and sensitivity and specificity for distant metastasis with MRI were 90.6%,75.0%and 92.5%,respectively,the same as those of MSCT.MRI and MSCT achieved the accuracy for TNM staging with 75.0% and 79.2%,83.3% and 66.7%,respectively for early gastric cancer,and 73.8% and 70.8%,respectively for advanced gastric cancer,with no significant difference between them(P>0.05).ConclusionCompared with MSCT,dynamically enhanced and delayed MRI with fat suppression was superior for revealing early stage of invasiveness and providing more evidences in T2 from T3 or T3 from T4 staging.Besides,MRI are more accurate than MSCT in T staging.