PET imaging of esophageal cancer

Esophageal cancer is the 8th most common cancer worldwide, and its mortality remains unacceptably high, with an overall 5-year survival rate of 20%. Males are more affected than females, and the peak incidence is in the sixth decade of life. Symptoms tend to arise late in the course of the disease, and commonly include dysphagia, odynophagia, and weight loss. Its main histological subtypes are squamous cell carcinoma (SCC) and adenocarcinoma. SCC is the most prevalent histology, but it has been surpassed in developed countries by adenocarcinoma over the last few decades subsequent to the rise in obesity and the decline of smoking and alcohol use. Imaging is essential to the management of esophageal cancer, as it guides clinical staging. Initial staging is multimodal, usually comprising endoscopic and cross-sectional imaging. 2-Deoxy-2-[18F]fluoroglucose ( 18 F- FDG) PET/CT plays an important role in metastases detection of distant disease, measurement of treatment response, and in the surveillance for recurrences post-esophagectomy. The metabolic information provided by the 18 F- FDG PET adds to the anatomic data CT yields, resulting in a synergistic modality capable of influencing clinical management in esophageal cancer. Moreover, there is mounting evidence supporting the use of 18 F- FDG PET standardized uptake value as an objective way to measure treatment response and even as a prognostic resource. More recent developments in the use of hybrid imaging combining nuclear medicine and radiology techniques culminated in PET/magnetic resonance imaging (MRI), which shows promising results in preliminary studies. Similar efforts have been put into the development of new radiopharmaceuticals that might enhance the diagnostic efficacy of PET imaging. Nuclear medicine is currently essential to provide the oncologist with fundamental information to guide esophageal cancer management and will continue to do so as new technologies are constantly being refined and tested.