• MDCT
• non-cardial gastric cancer

Purpose. The aim of this study was to evaluate diagnostic accuracy of currently used MDCT criteria in the tumor and nodal staging of non-cardial gastric cancer and to identify more accurate criteria, especially in order to reach a better accuracy in the nodal staging, comparing MDCT evaluation with pathological results.

Materials and methods. Nineteen patients with non-cardial gastric cancer underwent to MDCT for staging in our department and then to surgery within the next 7 to 72 days (average 20 days). Only patients with an optimal gastric distension at the MDCT and who did not take neoadjuvant therapy were considered. The gold standard was the pathological evaluation. MDCT was performed using a 64-detector row CT scanner; images were obtained before and after the intravenous administration of non-ionic contrast material, exactly in the arterial and venous phases; if necessary, a later phase and/or an acquisition in lateral or prone position were made. T and N-staging were blinded evaluated according to currently used CT criteria; subsequently another not blinded N-staging evaluation was made, in order to identify new criteria to improve staging diagnostic accuracy.

Results. Tumor volume significantly correlates with pT and maximum tumor thickness with pT2 and pT3; none of these variable have shown a relation with pN.
T-staging overall diagnostic accuracy ranges from 0.62 and 0.89 and was comparable between a series of imaging of 2.5mm slice thickness/2.5mm reconstruction interval and a series of 2.5mm slice thickness/1.25mm reconstruction interval.
According to different evaluation systems applied, N-staging accuracy ranges between 0.68 and 0.84, sensitivity between 0.69 and 0.93, specificity between 0.50 and 0.67, PPV between 0.79 and 0.82, NPV between 0.50 and 1.

Conclusions. MDCT has a good diagnostic accuracy in T and N-staging of non-cardial gastric cancer that can be improved using volumetric MDCT acquisition with isotropic or near-isotropic voxel and subsequent Multiplanar Reformation (MPR).