Advanced gastric carcinoma: the role of three-dimensional and axial imaging by spiral CT

Background: The purpose of this study was to assess the role of three-dimen sional (3D) and axial imaging by spiral computed tomography (CT) in the eva luation of advanced gastric carcinoma (AGC). Methods: Sixty patients with AGC underwent 3D and axial imaging by spiral C T. Among them, 40 cases were confirmed by surgery. The remaining 20 cases s howed typical findings of AGC with upper gastrointestinal series and gastro scopy that were proved by endoscopic biopsy. Spiral CT was performed with 3 -mm collimation, 4.5-mm/s table feed, and 1.5-mm reconstruction interval in the supine position after ingestion of gas. Three-dimensional images using the shaded surface display (SSD) technique were analyzed and graded (excel lent, good, or poor). A second dual-phase spiral CT scan was performed with 5-mm collimation, 7-mm/s table feed, and 5-mm reconstruction interval in t he prone position after ingestion of water. Results: Among 60 cases of AGC, there were two cases (3.4%) of Borrmann typ e 1, 12 cases (20.0%) of Borrmann type 2, 32 cases (53.3%) of Borrmann type 3, 11 cases (18.3%) of Borrmann type 4, and three cases (5.0%) of Borrmann type 5. Of the 60 cases of AGC, excellent 3D images were obtained in nine patients (15.0%), good 3D images in 39 (65.0%), and poor 3D images in 12 (2 0.0%). Among the 12 patients with poor images, cancers were located at the pyloric antrum in eight cases (66.7%), were AGC Borrmann type 4 in three ca ses (25.0%), and early gastric carcinoma (EGC)-mimicking lesion (AGC Borrma nn type 5) in one case (8.3%). Cancers involving the antrum tended to show poor images (p < 0.05). Using axial images, Borrmann's classification based on tumor morphology was accurately identified in 41 cases (68.3%); however , using 3D imaging, 52 cases (86.7%) were accurately classified (p < 0.05). In 40 cases receiving surgery, good correlation between axial CT image and pathology occurred in 70.0% of T class and 72.5% of N class. Conclusions: Three-dimensional images of AGC by spiral CT data were good or excellent in 80%, and combining 3D images with axial CT imaging improved t he accuracy in classifying Borrmann type and tumor staging.