Despite negative bronchoscopic findings CT-guided core biopsies will deliver sufficient specimens for histopathological tests in 95% of patients with uncertain thoracic lesions. Infiltrations surrounding the vital part of the tumor may obscure the correct targeting and lead to false negative results in a few patients. Severe complications were not seen in this study, although they might happen in rare cases according to reports in the literature. Therefore CT-guided core biopsies represent an efficient and safe procedure in patients with thoracic lesions.