The mediastinum in non-small cell lung cancer: CT-surgical correlation.

Computed tomography was used to evaluate the mediastinum preoperatively in 60 patients with non-small cell lung cancer; 49 of these patients had thorough surgical-pathologic determination of mediastinal node status. Mediastinal lymph nodes were located by CT using the node-mapping scheme suggested by the American Thoracic Society and were considered abnormal when larger than 100 mm2 in cross-sectional area. The sensitivity of CT was 95% in detecting malignant mediastinal adenopathy; however, specificity was only 64%. Receiver operating characteristic (ROC) curve analysis showed that the optimal size criterion for diagnosing malignant mediastinal adenopathy is 1.0-1.5 cm when the short axis of a node is measured. CT staging of the mediastinum in patients with non-small cell lung cancer is clinically useful; negative mediastinal CT makes mediastinoscopy unnecessary, whereas positive CT should lead to biopsy of the enlarged node.