ABSTRACT
Objective To evaluate the value of volume measured by multi-slice spiral CT in preoperative N staging of gastric canc-er.Methods CT data of 1 93 cases of gastric cancer proven pathologically were collected and analyzed.Volume of the tumor was cal-culated in the portal phase,and the correlation between the results and N staging was evaluated.ROC curve was used to get diagnos-tic value to differentiate N stages.Results Intra-observer Kappa value was 0.77 (P < 0.05 ),0.72 (P < 0.05 ),Inter-observer Kappa value was 0.69 (P <0.05).The tumor volume data was positively correlated with different N stages (r=0.568,P <0.05). ROC curve showed that the volume could help differentiate between stage N0 and stage N1 - N3 (cutoff 12.06 cm3 ,sensitivity 55%,specificity 95%),stage N0-N1 and stage N2-N3 (cutoff 22.35 cm3 ,sensitivity 66%,specificity 86%),stage N0-N2 and stage N3 (cutoff 25.95 cm3 ,sensitivity 62%,specificity 89%)respectively.Conclusion The volume of gastric cancer measured by CT plays an important part in predicting lymph node metastasis staging and optimizing individualized clinical strategy for patients.