Diagnosis of early central lung cancer with CT. Correlation with bronchoscopic and histopathologic findings

Objective: To study the CT findings of early central lung cancer and correlative pathologic basis, and to evaluate the role of CT in the differential diagnosis of central lung cancer. Methods; Seventeen patients with early central lung cancer and 10 patients with benign lesions resembling the central lung cancer were analyzed. Thin-section CT was performed with a section thickness of 3 mm or 1.5 mm at Philips SR 7000 or GE Lightspeed Plus scanner. The visibility of the lesions was correlated with bronchoscopic and histopathologic findings. Results: All 17 lesions were visualized at CT. Three lesions showed focal bronchial wall thickening and internal bronchial wall irregularity, bronchial mucous coarsening, redness and swollen at bronchoscopy. Fourteen lesions showed focal narrowing or obliteration of the bronchial lumen, 4 complicated with subsegmental bronchial mucoid impaction, 10 with obstructive pneumonia or atelectasis. Corresponding bronchoscopic view disclosed intraluminal polyploid protrusions. The epithelia were involved in 1 case, subepithelia in 5, and cartilaginous involvement in 11 according to the depth of invasion of the bronchial wall at histopathology. Among 10 patients with benign lesions, 6 cases were suspected as bronchogenic carcinoma and the possibility of bronchogenic carcinoma was not excluded at CT in 4 cases. There were 5 patients with uneven thickening of internal bronchial wall, 2 with lumen blood clots, 1 with lumen nodule, and no abnormalities in 2 patients at bronchoscopy. Conclusion: Thin-section CT has been proved to be a reliable method for demonstrating the mild changes of the bronchi and to be a valuable tool for the diagnosis of early central lung cancer