Predictive Value of 18F-Fluorodeoxyglucose Positron Emission Tomography/Computed Tomography (18F-FDG PET/CT) Imaging for Prognosis in Patients with Gastric Cancer Undergoing Surgery

doi:10.16458/j.cnki.1007-0893.2025.20.017

Abstract：Objective: To investigate the predictive value of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) imaging for the prognosis of patients with gastric cancer undergoing surgery. Methods: A retrospective analysis was conducted on the medical records of 80 patients with gastric cancer admitted to Gaozhou People's Hospital from January 2021 to June 2023. All patients underwent 18F-FDG PET/CT examination before surgery. Patients were followed up for 2 years to observe their prognosis. The maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), maximum diameter, and gastric wall thickness of the primary lesion were compared between patients with different prognoses. The predictive value of each indicator individually and in combination for the prognosis of patients after gastric cancer surgery was evaluated, and the correlation between SUVmax of the primary lesion and MTV, maximum diameter, and gastric wall thickness was analyzed. Results: After 2 years of follow-up, 29 out of 80 patients died (36.25%) and were classified into the death group, while 51 patients survived (63.75%) and were classified into the survival group. The average survival time was (18.67±3.62) months. The SUVmax of the primary lesion in the death group was (17.98±2.63), MTV was (18.38±2.41) cm³, maximum diameter was (7.61±1.26) cm, and gastric wall thickness was (22.49±4.63) mm, all of which were higher than those in the survival group [(6.67±1.24), (7.52±1.19) cm³, (5.10±1.04) cm, (15.28±3.15) mm], with statistically significant differences (P<0.05). The receiver operating characteristic (ROC) curve showed that the combined test had an area under the curve (AUC) of 0.907, sensitivity of 0.897, and specificity of 0.667, all higher than those of any single test. Pearson correlation analysis showed that SUVmax of the primary lesion had no significant correlation with the maximum diameter of the primary lesion (r=0.241, P=0.138), but was positively correlated with MTV and gastric wall thickness (r=0.779, 0.782, both P<0.001). Conclusion: SUVmax, MTV, maximum diameter, and gastric wall thickness of the primary lesion were highly expressed in 18F-FDG PET/CT imaging for patients with gastric cancer. Combined testing has a high predictive value for the prognosis of patients after gastric cancer surgery and can provide important reference for clinical doctors to further assess the progression of the disease.