From 09/2007 to 05/2009, in Cho Ray Hospital, 45 patients including 35 lung tumors and 10 mediastinal tumors underwent transthoracic biopsies using 22G spinal needles and 16G Tru-cut needles. Results: 45 cases, including malignant: 42 cases (93.3%) (adenocarcinoma of lung: 66.7%); benign: 3 cases (6.7%).