A Clue for the Diagnosis of Lung Cancer Looking Lobar Consolidation with Emphasis on Thickness and Enhancement Pattern of Bronchial Wall on CT

ABSTRACT

PURPOSE: To differentiate between lung cancer and pneumonia for cases of lobar consolidation, with an emphasis on the thickness and enhancement pattern of the bronchial wall viewed by a CT. MATERIALS AND METHODS: We retrospectively analyzed 17 patients with evidence of lobar consolidation, from a simple-chest radiograph, and divided them into groups by condition (lung cancer, n = 5; pneumonia, n = 12). CT scans were performed on all patients and bronchial wall thickness, which is the cranio-caudal length of the bronchial wall thickness and the enhancement pattern, were measured and analyzed at the mediastinal window setting. RESULTS: The thickness of the bronchial wall in the lung cancer group (2.46+/-0.37 mm) was significantly greater than the pneumonia group (1.73+/-0.36 mm) (p = 0.002). Moreover, the bronchial wall thickness was greater than 2.0 mm for all patients in the cancer group. Further, if a diagnostic criterion was set to be larger than 2.0 mm, 100% sensitivity and 66.7% specificity would be achieved for the study subjects. The cranio-caudal length of the bronchial wall thickness in the cancer group was 37.5+/-16.4 mm, which was significantly greater than the pneumonia group (16.3+/-6.6 mm) (p = 0.001). We found no significant difference for the degree of contrast enhancement between the two groups. CONCLUSION: A CT scan measurement of the bronchial wall thickness greater than 2 mm in CT scans can be an indicator for diagnosing lung cancer in patients with lobar consolidation.