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Esophageal cancer: biology, natural history, staging and therapeutic options.

The distribution of adenocarcinomas and squamous cell carcinomas in esophageal cancer (EC) has changed, and focus directed towards tumors of the distal esophagus and the esophagogastric junction. The genetic events leading to EC are not fully clarified, but important risk factors have been identified. Accurate pretherapeutic tumor evaluation should be provided for a multi-disciplinary and individually tailored patient management programme. Endoscopic ultrasonography (EUS) and PET-CT play an important role in the assessment of disease, evaluation of treatment response and during follow-up.