[Two-phase dynamic CT findings of gastric carcinoma and its value for tumor detection and gross classification].

OBJECTIVE: To analyze the two-phase dynamic CT features of gastric carcinoma and to assess its usefulness for tumor detection and gross classification. METHODS: Two-phase dynamic CT was performed in 63 cases of gastric carcinoma proved histologically by fibro-gastroscopic biopsy. CT features of gastric carcinoma, tumor detection, and gross classification were correlated with surgical and pathologic findings. RESULTS: The detectability by two-phase enhanced CT scanning of early and advanced gastric carcinoma was 100% and 98.2%, respectively. The overall accuracy of gross classification for advanced carcinoma was 65.4%, but for early gastric carcinoma, it was 0. The accuracy of Borrmann type II, III, IV was 85.7%, 100%, 55.6%, respectively. In the first phase (early enhancing phase) CT scan, the manifestation of early gastric carcinoma included local thickening of gastric wall, moderate or marked heterogeneous enhancement of lesions in 4 cases and mild enhancement in the other 4 cases. Local or extensive thickening of gastric wall, with or without ulceration, moderate or marked heterogeneous enhancement in early enhancing phase were shown in advanced gastric carcinoma. In the second phase, the degree of tumor enhancement in advanced carcinoma was slightly higher than that of the normal part of gastric wall. There were 4 cases with mucinous adenocarcinoma, a target or laminary appearance was present in 3 cases, and intramural calcification was present in 2 cases. CONCLUSION: 1. Enhanced dynamic CT scan plays a significant role in the diagnosis of gastric carcinoma, early enhancing phase scanning is the technique of choice nowadays for demonstrating tumor lesions. 2. Sophisticated scanning technique is mandatory in improving the diagnostic accuracy of gastric carcinoma.