Objectives: Neoadjuvant therapy for the treatment of oesophageal cancer was introduced in an effort to improve prognosis. Response assessment is crucial for the treatment of patients with oesophageal cancer. Currently, ¹⁸F-fluorodeoxyglucose positron emission tomography (¹⁸F-FDG PET) seems to be the best available tool to assess neoadjuvant therapy response in patients with oesophageal cancer. The purpose of this study was to assess the diagnostic value of ¹⁸F-FDG PET for the evaluation of neoadjuvant therapy responses in patients with oesophageal cancer using a meta-analysis. A unified procedure and evaluation standard for ¹⁸F-FDG PET in the assessment of neoadjuvant therapy response should be established.
Methods: All published English-language studies pertaining to the assessment of neoadjuvant therapy response in patients with oesophageal cancer using ¹⁸F-FDG PET in the MEDLINE and EMBASE databases were collected. The methodological quality of the included studies was evaluated according to the Quality Assessment of Diagnostic Accuracy Studies quality assessment tool. Pooled sensitivity, specificity, diagnostic odds ratios and summary receiver operating characteristic curves were obtained using statistical software.
Results: Thirteen studies included in the meta-analysis fulfilled the inclusion criteria of the Quality Assessment of Diagnostic Accuracy Studies quality assessment tool. The pooled sensitivity, specificity and diagnostic odds ratios for F-¹⁸FDG PET in the evaluation of neoadjuvant therapy response in patients with oesophageal cancer were 70.3% [95% confidence interval (CI): 64.4-75.8], 70.1% (95% CI: 65.1-74.8) and 9.389 (95% CI: 3.482-25.319), respectively. The area under the curve and the Q value for the summary receiver operating characteristic curve were 0.8244 and 0.7575, respectively.
Conclusion: ¹⁸F-FDG PET has some value in the assessment of neoadjuvant therapy response in patients with oesophageal cancer. A 50% reduction in standardized uptake value between pretherapy and posttherapy positron emission tomography scans performed in the first 2 weeks after the initiation of neoadjuvant therapy is the optimal condition for predicting a response to neoadjuvant therapy in patients with oesophageal cancer.