Updated evidence on the accuracy of 18F-fluorodeoxyglucose positron emission tomography/computed tomography in esophageal cancer staging: a systematic review of studies published between 2017 and 2024

Background: Appropriate staging of esophageal cancer is crucial for optimizing treatment planning and enhancing patient outcomes. 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) has emerged as a key imaging technique for assessing lymph node and distant metastases in esophageal cancer. In this systematic review, we aimed to assess the diagnostic performance of 18F-FDG PET/CT in staging esophageal cancer, including its sensitivity, specificity, and clinical utility in tumor detection, lymph node status, treatment response, and prognostication. Methods: A systematic literature search was conducted between 2017 and 2024 using MEDLINE, Embase, LILACS, and ClinicalTrials.gov databases. Studies assessing the diagnostic accuracy of 18F-FDG PET/CT for esophageal cancer staging were included. The Quality Assessment of Diagnostic Accuracy Studies version 2 (QUADAS-2) tool was used to assess risk of bias. Data extraction focused on the sensitivity, specificity, predictive value, and relative accuracy compared with other imaging methods. Results: A total of 22 studies were included in this review out of 182 initially selected studies. The sensitivity of 18F-FDG PET/CT for tumor staging ranges from 70% to 94%, and the specificity ranges from 60% to 78%. PET/CT sensitivity for lymph node metastases ranged from 60% to 85%, and the specificity ranged from 70% to 95%. PET/CT was also effective in detecting distant metastases (sensitivity: 85–95%) and in identifying responses to treatment by measuring the reduction in maximum standardized uptake value (SUVmax). However, false-positive findings have been observed due to inflammatory changes and limitations in detecting tiny metastases. Conclusions: 18F-FDG PET/CT is an important adjunct for esophageal cancer staging with excellent sensitivity for tumor and nodal staging. However, it has certain limitations in detecting tiny lesions and post-treatment inflammatory changes. Future research should aim to standardize imaging protocols, combine PET/CT with techniques like endoscopic ultrasound (EUS) and magnetic resonance imaging (MRI), and optimize SUVmax cutoff points to improve diagnostic accuracy.