Squamous cell carcinoma (SCC) and adenocarcinoma account for over 95 percent of esophageal malignant tumors. For most of the twentieth century, SCC has predominated. In the 1960s, SCC accounted for more than 90 percent of all esophageal tumors in the United States, and adenocarcinomas were considered so uncommon that some authorities questioned their existence. For the past two decades, however, the incidence of esophageal adenocarcinoma has increased dramatically in Western countries, such that the adenocarcinoma now accounts for >60 percent of all esophageal cancers in the United States. In contrast, worldwide, squamous cell cancer still predominates [1]. (See “Epidemiology, pathobiology, and clinical manifestations of esophageal cancer”.)
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Diagnosis and staging of esophageal cancer