CT volumetry for gastric adenocarcinoma: association with lymphovascular invasion and T-stages.

PURPOSE: To determine whether gross tumor volume of resectable gastric adenocarcinoma on multidetector computed tomography could predict presence of lymphovascular invasion and T-stages. RESULTS: Gross tumor volume increased with the lymphovascular invasion (r = 0.426, P < 0.0001) and T stage (r = 0.656, P < 0.0001). Univariate analysis showed gross tumor volume could predict lymphovascular invasion (P < 0.0001). Multivariate analyses indicated gross tumor volume as an independent risk factor of lymphovascular invasion (P = 0.026, odds ratio = 2.284). The Mann-Whitney U test showed gross tumor volume could distinguish T2 from T3, T1 from T2-T4a, T1-T2 from T3-T4a and T1-T3 from T4a (P = 0.000). In the development cohort, gross tumor volume could predict lymphovascular invasion (cutoff, 15.92 cm3; AUC, 0.760), and distinguish T2 from T3 (cutoff, 10.09 cm3; AUC, 0.828), T1 from T2-T4a (cutoff, 8.20 cm3; AUC, 0.860), T1-T2 from T3-T4a (cutoff, 15.88 cm3; AUC, 0.883), and T1-T3 from T4a (cutoff, 21.53 cm3; AUC, 0.834). In validation cohort, gross tumor volume could predict presence of lymphovascular invasion (AUC, 0.742), and distinguish T2 from T3 (AUC, 0.861), T1 from T2-T4a (AUC, 0.859), T1-T2 from T3-T4a (AUC, 0.875), and T1-T3 from T4a (AUC, 0.773). MATERIALS AND METHODS: 360 consecutive patients with gastric adenocarcinoma were retrospectively identified. Gross tumor volume was evaluated on multidetector computed tomography images. Statistical analysis was performed to determine whether gross tumor volume could predict presence of lymphovascular invasion and T-stages. Cutoffs of gross tumor volume were first investigated in 212 patients and then validated in an independent 148 patients using area under the receiver operating characteristic curve (AUC) for predicting lymphovascular invasion and T-stages. CONCLUSIONS: Gross tumor volume of resectable gastric adenocarcinoma at multidetector computed tomography demonstrated capability in predicting lymphovascular invasion and distinguishing T-stages.