Correlation Between Tumor Uptake on FDG-PET and Malignant Features in Esophageal Squamous Cell Carcinoma After Neoadjuvant Chemotherapy Followed by Surgery

Background/Aim: To identify the correlations between the 18F-fluorodeoxyglucose (FDG) uptake on positron emission tomography (PET) images and the pathological features and recurrence among patients with esophageal squamous cell carcinoma (ESCC) who were administered neoadjuvant chemotherapy (NAC) followed by surgery. Patients and Methods: We assessed the correlations between the maximum standardized uptake value (SUVmax) of primary tumors as reflected on preoperative FDG-PET images, the pathological features, and cancer recurrence in 124 patients with locally advanced ESCC, who were treated with NAC and esophagectomy. Results: The pre-NAC SUVmax significantly differed for the ypT status and venous invasion (VI). The post-NAC SUVmax (post-SUVmax) significantly differed for the ypT and ypN status, VI, lymphatic invasion (LI), pathological tumor response, down-staging, and recurrence. The decrease in SUVmax before and after NAC (ΔSUVmax) significantly differed for ypT status, LI, VI, pathological tumor response, down-staging, and recurrence. The survivals were significantly stratified according to the optimal cutoffs of SUVmax for predicting recurrence (post- and ΔSUVmax cutoffs: 4.2 and 30, respectively; all p<0.0001). Moreover, multivariate analysis showed that the post- and ΔSUVmax were independent predictive factors for recurrence-free survival. Conclusion: The SUVmax on preoperative FDG-PET can predict the degree of aggressiveness of the tumor in locally advanced ESCC treated with NAC.