Abstract: Objective To study the differential imaging diagnosis of solitary tuberculosis and peripheral lung cancer.Methods CT images of 15 cases of tuberculosis and 24 cases of peripheral lung cancer confirmed by surgical pathology and clinical analysis were retrospectively analyzed. Among the 15 tuberculosis,7 cases had chest CT plain scans, 8 cases had chest CT plain scans and enhanced scans, and 3 cases were examined by 18F-FDG PET/CT. Among the 24 lung cancer cases, 4 cases had chest CT plain scans 20 cases had chest CT plain scans and enhanced scans and 2 cases were examined by 18F-FDG PET/CT. The CT and PET/CT signs were comprehensively analyzed. Results The probabilities of calcification and smooth edges among tuberculosis patients (7/15, 4/15) were higher than peripheral lung cancer patients (1/24, 0/24)(P<0.05、P<0.05). The probabilities of lobulation signs, speculation signs and enhancement>20HU among tuberculosis patients (4/15, 5/15, 2/15) were lower than peripheral lung cancer patients (18/24, 17/24, 17/24) (P<0.05、P<0.05、P=0.001).There were no significant differences in lesion diameters, cavities,and pleural indentation or thickening between tuberculosis patietns and peripheral lung cancer patients (P>0.05). The SUVmax of tuberculosis was lower than that of peripheral lung cancer, however, the differences were not significant. Conclusion CT signs of tuberculosis and peripheral lung cancer are characteristic, and some of them overlap. Reasonable combination of PET/CT is of great value for the diagnosis of tuberculosis and peripheral lung cancer.

Key words: Tuberculosis, Lung cancer, Tomography/X-ray computed, Positron emission tomography