BACKGROUND: Responses of esophageal cancer to neoadjuvant therapy and patient prognosis are difficult to predict preoperatively. This study aimed to determine the ability of fluorine-18 fluorodeoxyglucose ((18)FDG) positron emission tomography (FDG-PET) to predict outcomes of trimodal therapy on esophageal squamous cell carcinoma (ESCC). METHODS: The responses of 111 patients with ESCC were monitored using FDG-PET before and after neoadjuvant chemoradiotherapy (nCRT) followed by surgical treatment. Associations between the maximum standardized uptake value (SUVmax) and pathologic responses (PRs) and prognosis were analyzed. RESULTS: Responses were significantly associated with SUVmax after nCRT (post-SUVmax) and with the rate of decreases in the SUVmax (%ΔSUVmax) of the primary tumor. The optimal cutoffs for post-SUVmax and %ΔSUVmax determined from receiver operating characteristic (ROC) curves were 2.7 (area under the curve [AUC], 0.68; 95% confidence interval [CI], 0.58-0.78; p = 0.001) and 75 (AUC, 0.64; 95% CI, 0.54-0.75; p = 0.01) for predicting a pathologic complete response (pCR) and 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 a good response according to Japan Esophageal Society response criteria. These values reliably separated patients into groups with and without pCR and with and without a good response. Multivariate analysis showed that %ΔSUVmax (≤70 and >70) was an independent prognostic factor for disease-specific survival (hazard ratio [HR], 0.45; 95% CI, 0.21-0.98; p = 0.04). CONCLUSIONS: SUVmax is a valuable preoperative predictor of tumor response and survival among patients who undergo trimodal therapy for ESCC.
BACKGROUND: Responses of esophageal cancer to neoadjuvant therapy and patient prognosis are difficult to predict preoperatively. This study aimed to determine the ability of fluorine-18 fluorodeoxyglucose ((18)FDG) positron emission tomography (FDG-PET) to predict outcomes of trimodal therapy on esophageal squamous cell carcinoma (ESCC). METHODS: The responses of 111 patients with ESCC were monitored using FDG-PET before and after neoadjuvant chemoradiotherapy (nCRT) followed by surgical treatment. Associations between the maximum standardized uptake value (SUVmax) and pathologic responses (PRs) and prognosis were analyzed. RESULTS: Responses were significantly associated with SUVmax after nCRT (post-SUVmax) and with the rate of decreases in the SUVmax (%ΔSUVmax) of the primary tumor. The optimal cutoffs for post-SUVmax and %ΔSUVmax determined from receiver operating characteristic (ROC) curves were 2.7 (area under the curve [AUC], 0.68; 95% confidence interval [CI], 0.58-0.78; p = 0.001) and 75 (AUC, 0.64; 95% CI, 0.54-0.75; p = 0.01) for predicting a pathologic complete response (pCR) and 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 a good response according to Japan Esophageal Society response criteria. These values reliably separated patients into groups with and without pCR and with and without a good response. Multivariate analysis showed that %ΔSUVmax (≤70 and >70) was an independent prognostic factor for disease-specific survival (hazard ratio [HR], 0.45; 95% CI, 0.21-0.98; p = 0.04). CONCLUSIONS: SUVmax is a valuable preoperative predictor of tumor response and survival among patients who undergo trimodal therapy for ESCC.