Prognostic value of quantitative parameters for esophageal squamous cell carcinoma determined by preoperative FDG-PET after trimodal therapy

Abstract

BackgroundAssociations between tumor metabolic and volumetric parameters determined by preoperative 18F-fluorodeoxyglucose–positron emission tomography and survival in patients with esophageal squamous cell carcinoma who underwent trimodal therapy have not been fully investigated. MethodsWe evaluated relationships between reductions in maximal standardized uptake value, metabolic tumor volume, and total lesion glycolysis in primary tumors on 18F-fluorodeoxyglucose–positron emission tomography images between before and after neoadjuvant chemoradiotherapy and the survival of 120 patients with esophageal squamous cell carcinoma who underwent neoadjuvant chemoradiotherapy followed by surgery. ResultsThe optimal cutoffs of Δ maximal standardized uptake value, Δ metabolic tumor volume, and Δ total lesion glycolysis were defined to statistically yield the largest differences in recurrence-free survival for good and poor positron emission tomography responders to neoadjuvant chemoradiotherapy (cutoffs: 70%, 85%, and 90%, respectively). These cutoff values significantly stratified overall survival (Δ maximal standardized uptake value, P = .004; Δ metabolic tumor volume, P = .001; Δ total lesion glycolysis, P < .0001). Univariate analysis showed that Δ maximal standardized uptake value (hazard ratio, 0.50; 95% confidence interval, 0.32–0.79; P = .003), Δ metabolic tumor volume (hazard ratio, 0.50; 95% confidence interval, 0.31–0.81; P = .004), and Δ total lesion glycolysis (hazard ratio, 0.37; 95% confidence interval, 0.23–0.61; P < .001) were statistically significant for recurrence-free survival. Furthermore, Δ metabolic tumor volume (hazard ratio, 0.45; 95% confidence interval, 0.27–0.76; P = .003) and Δ total lesion glycolysis (hazard ratio, 0.37; 95% confidence interval, 0.22–0.63; P < .001) were independent factors for recurrence-free survival in multivariate analyses that included preoperative and pathological factors. ConclusionTogether with significant pathological prognostic factors, Δ metabolic tumor volume and Δ total lesion glycolysis were valuable for patients with esophageal squamous cell carcinoma who received trimodal therapy. Thus, preoperative 18F-fluorodeoxyglucose–positron emission tomography is a useful and noninvasive diagnostic tool that might facilitate tailoring optimal therapies for locally advanced esophageal squamous cell carcinoma.