Value of 18 F-FDGPET/CT in detecting recurrence and metastasis in gastric carcinoma

Abstract

Objective PET with 18F-fluorodeoxyglucose (FDG) has been used to beth detect and stage a variety of malignancies. The aim of this retrospective study was to evaluate the clinical value of 18F-FDG PET/CT for recurrence and metastasis in gastric carcinoma patients after total gastrectomy. Methods A total of 45 gastric carcinoma patients who underwent total gastrectomy were included. PET/CT scans were obtained for restaging. The gold standard of 18F-FDG PET/CT diagnostic accuracy was based on either histopathology or clinical follow-up. By using the t-test from SPSS 11.5, the cut-off of maximum standard-ized uptake values (SUVmax) from 18F-FDG to differentiate benign from malignant lesion at stomach were determined and calculated. Results (1) Of the 45 patients, 22 were suspicion recurrent lesion at stomach. Of the 22 patients, 12 were confirmed to have recurrent lesions. The diagnostic accuracy were 100.0% (12/ 12) for sensitivity, 70.0% (7/10) for specificity, and 86.4% (19/22) for accuracy, respectively. A higher SUVmax in malignant than benign lesion was noted (6.27 ± 3.42 vs 3.92 ± 2.24), though not reached to the significance (t = 1. 862, P > 0.05). (2) For extra-gastric lesion detection, the sensitivity, specificity, and accuracy for region lymph nodes were 78.9% (15/19), 92.3% (24/26), and 86.7% (39/ 45), for peritoneal spreading were 6/9, 97.2% (35/36), 91. 1% (41/45), and for distant sites were 86.7%(13/15), 93.3% (28/30), 91.1% (41/45). (3) False positive were found in eight sites. All were either inflammatory or physiological uptake at intestine. False negative were found in nine sites. Either due to small in size (less than 1.0 cm in diameter), well differentiation of the tumor cell or with a nature of signet ring. Conclusion 18F-FDG PET/CT had a potential to detect local, regional, and distant metastasis in gastric cancer. Key words: Stomach neoplasms ; Neoplasm reccurence,local ; Neoplasm metastasis ; Tomography,emission-computed ; Tomography,X-ray computed ; Deoxyglucose ;