Objective: The purpose of this study is to retrospectively evaluate the diagnostic accuracy and complications of C-arm cone-beam CT (CBCT)-guided percutaneous transthoracic needle biopsy (PTNB) for small (≤ 20 mm) lung nodules and their possible influencing factors.
Materials and methods: From March 2009 to July 2010, 161 consecutive patients (77 men and 84 women; mean [± SD] age, 61 ± 11.8 years; range, 29-85 years) with 173 small (≤ 20 mm) lung nodules underwent CBCT-guided PTNB performed by an experienced chest radiologist in a tertiary referral hospital. The diagnostic accuracy, sensitivity, specificity, and complication rates were statistically evaluated, and influencing factors were assessed using univariate and subsequent multivariate analysis.
Results: Of 173 nodules (mean size, 15 ± 3.7 mm), 94 (54.3%) were diagnosed as malignant, 69 (39.9%) as benign, and 10 (5.8%) as indeterminate. On PTNB, 160 nodules were correctly diagnosed and three were false-negatives. Diagnostic accuracy, sensitivity, and specificity were 98.2%, 96.8%, and 100%, respectively. No factors significantly decreased diagnostic accuracy. As for complications, pneumothorax, hemoptysis, and chest pain occurred in 55 (31.8%), 25 (14.5%), and two (1.2%) patients, respectively. Multivariate analysis revealed that the presence of emphysema along the needle pathway was a significant risk factor (odds ratio [OR], 10.11), and the occurrence of hemoptysis was a significant protective factor (OR, 0.28) against pneumothorax. Ground-glass nodules were found to be a significant independent risk factor for hemoptysis (OR, 5.10).
Conclusion: C-arm CBCT-guided PTNB is highly accurate for small lung nodules, and the diagnostic accuracy does not significantly decrease even in technically challenging conditions.