[Value of computed tomography in the diagnosis of the intrathoracic extension of bronchial cancer].

In 76 patients the diagnosis of the mediastinal extension of a bronchial cancer, assessed by computed tomography (CT), was compared to histological specimens obtained by mediastinoscopy and surgery (58/76). The extension to mediastinal nodes was present in 26 subjects (34.2%) and yet was not recognised 15 times on CT. There were 15 false negatives (FN) and 3 false positives (FP). Sensitivity 43%, specificity 94%, predictive value for positives (VPP) 70%, predictive value for negatives (VPN) 75%. Extension was present in 18 patients. These were recognised 14 times by CT. There were no false positives. (Sensitivity 70%, specificity 100%, VPP 100%, VPN 94%). We conclude That CT is useful for diagnosing direct mediastinal extension and allows the juxta-hilar extension of the cancer to be assessed. CT has no place in the diagnosis of mediastinal gland involvement. Mediastinoscopy (5.2% FN; no FP) is better than TDM for the diagnosis of extension to the mediastinal nodes both for peripheral and central cancers.