Incremental value of 18F-FDG PET/CT in therapeutic decision-making of potentially curable esophageal adenocarcinoma

AIMS AND OBJECTIVES: The aim of the study was to estimate the incremental value of fluorine-18 fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) in aiding treatment decisions in a specific cohort of patients with lower esophageal and gastroesophageal junction adenocarcinoma who were considered for potentially curative treatment on the basis of conventional imaging. MATERIALS AND METHODS: The study included patients referred for a staging F-FDG PET/CT who were considered for potentially curative treatment (neoadjuvant therapy followed by surgery or definitive chemoradiotherapy) by a multidisciplinary tumor board. The proportion of patients with M1b disease (American Joint Committee on Cancer, 6th ed.) detected on F-FDG PET/CT was calculated. The sensitivity, specificity, positive and negative predictive values, and accuracy of F-FDG PET/CT for M1b disease were calculated. PET/CT findings were verified with histopathological analysis; when it was not possible to obtain pathological confirmation, correlative imaging or follow-up imaging studies were used for validation. RESULTS: A total of 156 patients who fulfilled the inclusion criteria were analyzed. F-FDG PET/CT detected M1b disease in 25 patients (16%), changing the intent of treatment from potentially curative to palliative. In five patients, PET/CT failed to detect distant metastases. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of F-FDG PET/CT for detecting M1b disease were 83.3, 98.4, 92.5, 96.1, and 95.3%, respectively. Additional surgical procedures (hemicolectomy and polypectomy) were performed in three patients because of the detection of a second primary cancer in the colon in two patients and a colonic dysplastic polyp in one patient. CONCLUSION: In patients who are considered to be potentially curable after conventional imaging, F-FDG PET/CT can detect unsuspected sites of distant metastases (M1b) in a significant number of cases and thus contribute to the clinical decision-making process. PET/CT should be an integral part of the staging workup of patients with esophageal adenocarcinoma.