Comparison of Two-dimensional CT with Virtual Gastrography Using Multi-detector CT in the Diagnosis of Early Gastric Cancer

ABSTRACT

PURPOSE: We compared the performance of virtual gastrography (VG) using multi-detector (MDCT) with two-dimensional (2D) CT in the diagnosis of early gastric cancer (EGC). MATERIALS AND METHODS: We performed conventional gastroscopy and MDCT examination after gaseous distension of the stomach in 50 consecutive patients who were confirmed as EGC by surgery and endoscopic mucosal resection. Unenhanced images were obtained in the prone position and contrast enhanced images were obtained in the supine position. Contrast enhanced imaging was done 70 seconds after intravenous injection of 150 mL of ionic contrast material at the rate of 3 mL/sec. 2D CT and VG images were analyzed by two radiologist with consensus to assess the location and gross morphologic type of EGC. Crosstabs were used to determine the diagnostic accuracy of EGC on 2D CT and VG. RESULTS: The diagnostic specificity for 50 patients with EGC was significantly higher with VG (72%) than with 2D CT (88%) (p<0.05). VG depicted EGC in eight patients (type I = 1; type IIa = 3; type IIb = 1; type IIc = 2; type IIa + IIc = 1) that were missed on the 2D CT. The lesions were located in the antrum (n = 6), angle (n = 1), and body (n = 1). However, VG frequently misdiagnosed EGCs of type IIb (n = 4), IIc (n = 1), and III (n = 1), as well as the location at the angle (n = 3), antrum (n = 1), and body (n = 1). CONCLUSION: VG showed excellent result in the detection of EGC compared with 2D CT. However, it had limitations in the diagnosis of EGC type IIb or gastric angle tumor.