Diagnostic value of positron emission tomography in gastric malignancy

Objective: A study was performed to evaluate the diagnostic value of positron emission tomography(PET) using 18F-fluorodeoxyglucose(FDG) in patients with gastric malignancy and correlated with computed-tomography. Methods: 32 patients suspected of gastric malignancy underwent 18F-FDG PET scan, and CT was additionally performed in 22 patients. These results were compared with the histopathological staging to evaluate the accuracy and usefulness of PET in gastric malignant tumor. Results: There are 25 malignant tumors and 7 benign diseases in the 32 patients. The sensitivity and specificity in detecting primary foci by PET was 84% and 5/7 respectively. When CT was used, the sensitivity and specificity was 88.9% and 4/5 respectively. For lymphnode metastasis PET scan was accurate in 80% compared with 76.5% from CT. The accuracy in identifying distant metastasis by PET and CT was 7/8 and 2/7 respectively. Conclusion: PET scanning is accurate and sensitive in detecting primary lesions and distant metastasis in gastric malignancy. It can provide valuable reference in the diagnosis of gastric malignancy.