DIAGNOSTIC PERFORMANCE OF 18F-FDG PET/CT FOR PRIMARY TUMOR DETECTION IN ESOPHAGEAL CARCINOMA

Abstract

Background: Detection of primary esophageal lesion is considered an essential step in initial disease assessment since treatment decisions depend on accurate staging. Although contrast-enhanced CT and endoscopic ultrasound continued to be the established imaging methods, 18F-FDG PET/CT provides additional metabolic information that facilitates tumor detection. This study evaluates the efficacy of 18F-FDG PET/CT for primary lesion identification in patients with esophageal carcinoma. Methods: Images of 100 patients with histologically proven esophageal cancer who underwent staging 18F-FDG PET/CT between 2019 and 2024 were reviewed retrospectively. PET findings were correlated with endoscopic and pathological results. Tumor detection rates were analyzed according to histologic subtype and tumor stage. Results: 18F-FDG PET/CT demonstrated the primary lesion in 91 patients. Detection rates were higher in squamous cell carcinoma than in adenocarcinoma (94.8% vs 85.7%; p = 0.03). Sensitivity was high in advanced disease but decreased in T1 tumors. Most missed lesions were superficial tumors or low-volume adenocarcinomas. Metabolic tumor size exceeded CT-defined tumor length in 37% of patients. Conclusion: 18F-FDG PET/CT is considered a reliable non-invasive diagnostic tool for evaluating the primary tumor in patients with esophageal carcinoma. Its major contribution is in locally advanced disease, where metabolic information may complement conventional imaging and assist in planning therapy management.