Assessment of conventional tomography and fibreoptic bronchoscopy in the diagnosis of potentially malignant chest opacities.

Conventional chest tomography and fibreoptic bronchoscopy were performed in 100 patients with a localised chest abnormality on their chest radiographs who had been referred with a possible diagnosis of bronchial carcinoma. Carcinoma was eventually confirmed in 74 cases and in 26 the lesion proved to be benign. The accuracy of tomography in the overall series was 83%, with a sensitivity of 92% and a specificity of 58%. These figures compare favourably with the results of other imaging techniques used in the diagnosis of bronchial carcinoma. In 50 patients bronchoscopy did not suggest carcinoma and in this group of patients 24 had a carcinoma and 26 a benign lesion. The accuracy of tomography in the bronchoscopy negative patients was 74%, the major source of error being the false positive category. The lesion eventually proved to be benign in 33% of the cases where tomography suggested malignancy, but when the tomograms suggested that the lesion was benign a tumour was found to be present in only 12% of cases.