Cuộc xâm lược màng ngoài tim được đề xuất bởi màng ngoài tim dày lên và / hoặc tràn dịch, sự lang quên của chiếc máy bay chất béo giữa khối u và màng ngoài tim, hoặc hàng loạt hiệu ứng trên màng ngoài tim | 72 N. R. Bogot and L. E. Quint Figure In a 57-year-old woman with esophageal adenocarcinoma CT shows a mid esophageal mass that compresses the left mainstem bronchus arrow . Bronchial invasion was confirmed bronchoscopically. sensitivity for tracheobronchial involvement ranges from 31 to 100 specificity from 68 to 98 and accuracies range from 74 to 97 25 . Imaging features suggesting invasion should be further evaluated with bronchoscopy and confirmed with biopsy. Pericardial invasion is suggested by pericardial thickening and or effusion obliteration of the fat plane between the tumor and the pericardium or mass effect upon the pericardium 10 26 . Extensive invasion is unresectable and minimal invasion may be resectable. Regional lymph node N staging Diagnosing metastatic disease to regional lymph nodes with CT is limited for two major reasons. First a bulky primary esophageal mass may obscure adjacent involved lymph nodes 26 . Second diagnosis of lymph node disease is based solely on size criteria. However enlarged nodes may be benign and reactive in nature whereas small nodes may harbor microscopic metastases. Several size criteria for lymph node enlargement have been suggested. Traditionally 10 mm has been considered the upper normal limit for paraesophageal lymph nodes. For subdiaphrag-matic nodes an upper normal threshold of 8 mm has been used with nodes between 6 and 8 mm considered as indeterminate 27 . However more recently Schroder and colleagues have found these figures to be overestimations 28 . In a histopathological study of specimens from 40 patients with esophageal squamous cell carcinoma 1196 lymph nodes were analyzed finding 129 lymph nodes with metastatic infiltration. CT in Esophageal Cancer 73 a b Figure In a 43-year-old man with newly diagnosed distal esophageal adenocarcinoma CT shows distal esophageal thickening representing the primary tumor a . There was metastatic disease to regional lymph nodes in the gastrohepatic ligament .