New TNM staging system for esophageal cancer: what chest radiologists need to know

Esophageal cancer is a leading cause of cancer-related deaths worldwide, and the 5-year relative survival rate remains less than 20% in the United States. The treatment of esophageal cancer should be stage specific for better clinical outcomes. Recent treatment paradigms tend to involve a multimodality approach to management, which includes surgical resection and preoperative or definitive chemoradiation therapy. Accurate pretreatment staging of esophageal cancer is integral for assessing operability and determining a suitable treatment plan. The American Joint Committee on Cancer (AJCC) and the Union for International Cancer Control (UICC) have published the seventh edition of the staging manual for cancer in the esophagus and esophagogastric junction. Unlike the sixth edition, the revised staging manual is data driven and harmonized with the staging of stomach cancer. Improvements include new definitions for the anatomic classifications Tis, T4, regional lymph node, N, and M and the addition of nonanatomic cancer characteristics (histopathologic cell type, histologic grade, and cancer location). Given the recent increase in the incidence of adenocarcinoma of the distal esophagus, esophagogastric junction, and gastric cardia, the staging of tumors in the esophagogastric junction has been addressed. Radiologists must understand the details of the seventh edition of the AJCC-UICC staging system for esophageal cancer and use appropriate imaging modalities, such as computed tomography (CT), endoscopic ultrasonography, and positron emission tomography/CT, for initial staging.