Prognostic Value of Quantitative 18F-FDG PET/CT Parameters Measured in Primary Tumors and Suspicious Lymph Nodes in Patients With Esophageal Carcinoma

Abstract Objective:Quantitative 18F-FDG PET/CT parameters have been described as prognostic indicators in esophageal cancer. The objective of this study isto evaluate the prognostic value of the maximum standardized uptake value (SUVmax), metabolic tumor value (MTV) and total lesion glycolysis (TLG) measured in the primary tumor and suspicious lymph nodes.Methods: A cohort study was performed to assess the association of SUVmax, MTV and TLG measured prior to and post neoadjuvant therapywithoverall survival (OS) of patients with esophageal cancer who received trimodal therapy. The quantitative techniques were applied in the primary tumor and suspicious lymph nodes. The OS rates were analyzed. Results: Before neoadjuvant therapy, 106 patients underwent PET/CT, and 39 patients underwent post-neoadjuvant therapy PET/CT exams. Before neoadjuvanttherapy, PET/CT showed that all the variables of the evaluated lymph nodes were statistically significant in predicting OS. Postneoadjuvanttherapy, none of the PET/CT variables of lymph nodes were related to prognosis. On the other hand, all primary tumor volumetric variables were related to overall survival. The MTV (HR: 4.66; 95% CI: 1.54-14.08) and TLG (HR: 4.86; 95% CI: 1.66-14.26) of the primary tumor post neoadjuvanttherapy and the variations in MTV (HR: 2.95; 95% CI: 1.01-3.52) and TLG (HR: 3.49; 95% CI: 1.01-3.52) of the primary tumor pre-to-post-neoadjuvanttherapy were prognostic variables. Conclusion: In patients with esophageal cancer, the burden of disease in suspicious lymph nodes and the primary tumor prior to therapy and the residual burden of disease in the primary tumor post therapy assessed by PET/CT were associated with prognosis.