Role of FDG-PET/CT in prediction of pathological tumor response and survival after trimodality therapy for esophageal squamous cell carcinoma.

Results We compared the SUVmax between good (Japan Esophageal Society response evaluation criteria grades 3/2; n = 87, 78.4 %) and poor (grade 1; n = 24, 21.6 %) responders. The SUVmax after nCRT (post-SUVmax) in good and poor responders were 2.7 ± 0.9 and 4.4 ± 2.2, respectively (p < 0.0001). The rates of the SUVmax decrease after nCRT (ΔSUVmax) in these patients significantly differed (71 ± 14% vs. 60 ± 21%, respectively, p = 0.003). The area under receiver operating characteristic curves (AUC) showed that the optimal cut-off for post-SUVmax and ΔSUVmax were 3.7 (AUC, 0.76; 95% CI, 0.63-0.89; P < 0.001) and 70% (AUC, 0.65; 95% CI, 0.52-0.78; P = 0.02) for predicting good responder, respectively, and that the patients could be separated into groups with and without good response using these cut-off values. The 5-year overall survival rate was significantly higher for patients with ΔSUVmax > 70% than ≥ 70 % (66% vs. 42%, p = 0.04), and multivariable analysis including preoperative factors also revealed ΔSUVmax (≥ 70/> 70%) as an independent prognostic factor for disease-specific survival (OR, 2.22; 95%CI, 1.02 4.76; p = 0.04).