Background Neoadjuvant chemoradiotherapy (nCRT) followed by surgery is a currently widely used strategy for locally advanced esophageal cancer (EC). However, the conventional imaging methods have certain deficiencies in the evaluation and prediction of the efficacy of nCRT. This study aimed to explore the value of functional imaging in predicting the response to neoadjuvant chemoradiotherapy (nCRT) in locally advanced esophageal squamous cell carcinoma (ESCC). Methods Fifty-four patients diagnosed with locally advanced ESCC from August 2017 to September 2019 and treated with nCRT were retrospectively analyzed. DW-MRI scanning was performed before nCRT, at 10–15 fractions of radiotherapy, and 4–6 weeks after the completion of nCRT. 18F-FDG PET/CT scans were performed before nCRT and 4–6 weeks after the completion of nCRT. These 18F-FDG PET/CT and DW-MRI parameters and relative changes were compared between patients with pathological complete response (pCR) and non-pCR. Results A total of 8 of 54 patients (14.8%) were evaluated as disease progression in the preoperative assessment. The remaining forty-six patients underwent operations, and the pathological assessments of the surgical resection specimens demonstrated pathological complete response (pCR) in 10 patients (21.7%) and complete response of primary tumor (pCR-T) in 16 patients (34.8%). The change of metabolic tumor volume (∆MTV) and change of total lesion glycolysis (∆TLG) were significantly different between patients with pCR and non-pCR. The SUVmax-Tpost, MTV-Tpost, and TLG-Tpost of esophageal tumors in 18F-FDG PET/CT scans after neoadjuvant chemoradiotherapy and the ∆ SUVmax-T and ∆MTV-T were significantly different between pCR-T versus non-pCR-T patients. The esophageal tumor apparent diffusion coefficient (ADC) increased after nCRT; the ADCduring, ADCpost and ∆ADCduring were significantly different between pCR-T and non-pCR-T groups. ROC analyses showed that the model that combined ADCduring with TLG-Tpost had the highest AUC (0.914) for pCR-T prediction, with 90.0% and 86.4% sensitivity and specificity, respectively. Conclusion 18F-FDG PET/CT is useful for re-staging after nCRT and for surgical decision. Integrating parameters of 18F-FDG PET/CT and DW-MRI can identify pathological response of primary tumor to nCRT more accurately in ESCC.

Background: Although the clinical complete response (cCR) for esophageal cancer patients after neoadjuvant chemoradiotherapy (nCRT) may be related to the good survival prognosis, the choice of conservative and surgical treatments is still controversial. This study sought to compare the clinical outcomes of these two treatments.Methods: A systematic search was conducted according to the guidelines of the Preferred Reporting Items for Systematic Reviews and Meta-Analyses of the PubMed, Embase, and Cochrane Library databases to retrieve articles published between January 1, 2010 and March 31, 2022 on the efficacy of conservative treatment or surgery in esophageal cancer patients who had achieved a cCR after nCRT The predominant endpoints were overall survival (OS), disease-free-survival (DFS), local recurrence, and distant metastasis.Odds ratios (ORs) were generated for the dichotomous variants by meta-analysis. The software implemented was Stata 16.0 MP. This research was prospectively registered under PROSPERO (registration number: CRD42022332143).Results: Ultimately, eight retrospective cohort studies and one randomized controlled trial, comprising 749 patients (nCRT group: 333 and nCRT + surgery group: 416), were included in the meta-analysis after two researchers independently assessed the risk of bias for all included studies. The 2-year OS [OR =1.239, 95% confidence interval (CI): 0.891 to 1.723] and 5-year OS (OR =1.369, 95% CI: 0.963 to 1.947) were comparable between the nCRT group and nCRT plus surgery (nCRT + S) group. Patients in the nCRT + S group had significantly longer DFS (2 and 5 years, OR ranging from 0.303 to 0.357) and lower local recurrence rate (OR =0.179, 95% CI: 0.104 to 0.291) than those in the nCRT group. However, the distant metastasis rate was similar between the nCRT group and the nCRT + S group.Conclusions: Esophageal cancer patients who achieved a cCR after nCRT and received an esophagectomy had better DFS and lower local recurrence than those who received conservative treatment; however, this DFS advantage did not lead to a significant difference in OS. Salvage surgery may be a feasible option for resectable patients who have local recurrence after achieving cCR.