CT imaging of coexisting pulmonary tuberculosis and lung cancer

Objective To study the CT characteristics of coexisting pulmonary tuberculosis and lung cancer. Methods One hundred and four patients of coexisting pulmonary tuberculosis and lung cancer proved by histology,cytology or clinical underwent CT examination.All patients were divided into two groups,groupⅠwere the patients with the lung cancer after tuberculosis or both found simultaneously (groupⅠa with peripheral lung cancer and groupⅠb with central lung cancer),groupⅡwith tuberculosis during lung cancer chemotherapy (groupⅡa with peripheral lung cancer and groupⅡb with central lung cancer).Imaging characteristics of tuberculosis and lung cancer were compared.χ2test and t test were used for the statistical analysis. Results Of 104 patients,there were 92 patients (88.5%) in groupⅠand 12 patients (11.5%) in groupⅡ.Seventy patients (76.1%) of lung cancer and tuberculosis were located in the same lobe and 22 patients (23.9%) in the different lobes in groupⅠ.There was no significant difference in distribution of tuberculosis between groupⅠand groupⅡ (χ2=4.302,P=0.507).The fibrous stripes,nodules of calcification and pleural adhesion of tuberculosis were statistically significant between the two groups (χ2=22.737,15.193,27.792,P<0.05).There were 33 central lung cancers and 71 peripheral lung cancers.In groupⅠa (64 patients of peripheral lung cancers),39 patients (60.9%) had typical manifestations and most of the lesions were≥3 cm (n=49,76.6%),solid lesions showed variable enhancement. Conclusions Secondary tuberculosis during lung cancer chemotherapy has the same CT characteristics with the common active tuberculosis.The morphology,enhancement pattern of lesion and follow-up are helpful for the diagnosis of lung cancer after tuberculosis. Key words: Tuberculosis,Pulmonary; Lung neoplasms; Tomography,X-ray computed