CT volumetry for gastric carcinoma: association with TNM stage

We evaluated the feasibility of performing CT volumetry of gastric carcinoma (GC) and its correlation with TNM stage.

This institutional review board-approved retrospective study was performed on 153 patients who underwent a staging CT study for histologically confirmed GC. CT volumetry was performed by drawing regions of interest including abnormal thickening of the stomach wall. Reproducibility of tumour volume (Tvol) between two readers was assessed. Correlation between Tvol and TNM/peritoneal staging derived from histology/surgical findings was evaluated using ROC analysis and compared with CT evaluation of TNM/peritoneal staging.

Tvol was successfully performed in all patients. Reproducibility among readers was excellent (r = 0.97; P = 0.0001). The median Tvol of GC showed an incremental trend with T-stage (T1 = 27 ml; T2 = 32 ml; T3 = 53 ml and T4 = 121 ml, P < 0.01). Tvol predicted with good accuracy T-stage (≥T2:0.95; ≥T3:0.89 and T4:0.83, P = 0.0001), M-stage (0.87, P = 0.0001), peritoneal metastases (0.87, P = 0.0001) and final stage (≥stage 2:0.89; ≥stage 3:0.86 and stage 4:0.87, P = 0.0001), with moderate accuracy for N-stage (≥N1:0.75; ≥N2:0.74 and N3:0.75, P = 0.0001). Tvol was significantly (P < 0.05) more accurate than standard CT staging for prediction of T-stage, N3-stage, M-stage and peritoneal metastases.

CT volumetry may provide useful adjunct information for preoperative staging of GC.

CT volumetry of gastric carcinoma is feasible and reproducible. Tumour volume <19.4 ml predicts T1-stage gastric cancer with 91% sensitivity and 100% specificity (P = 0.0001). Tumour volume >95.7 ml predicts metastatic gastric cancer with 87% sensitivity and 78.5% specificity (P = 0.0001). CT volumetry may be a useful adjunct for staging gastric carcinoma.