Assessment of Independent Risk Factors of Developing Pneumothorax During Percutaneous Core Needle Lung Biopsy: Focus on Lesion Depth

BACKGROUND Previous studies identifying risk factors for pneumothorax in percutaneous core needle lung biopsies reported inconsistent and contradictory results. OBJECTIVES We aimed to identify independent risk factors for pneumothorax associated with computed tomography (CT)-guided percutaneous core needle lung biopsy (PCNB). PATIENTS AND METHODS We retrospectively reviewed 591 biopsy procedures for focal lung lesions. Risk factors for pneumothorax as a complication after lung biopsy were determined by univariate and multivariate analyses of variables including the patient's age, gender, lesion depth from the pleural surface, lesion size, lesion location, presence or absence of fissure crossing by the needle, emphysema in the same lobe where the biopsy was performed, and the final diagnosis of the biopsy lesion. RESULTS Pneumothorax occurred in 100 (16.9%) of 591 procedures. Based on univariate analyses, significant risk factors affecting the incidence of pneumothorax were patient gender (P = 0.039), lesion depth from the pleural surface (P < 0.001), fissure crossing by the needle (P = 0.002), and the presence of emphysema (P = 0.009). From the multivariate analysis, an increased rate of pneumothorax was strongly correlated with lesion depth from the pleural surface (odds ratio [OR], 1.71; 95% confidence interval [CI], 1.50 - 1.96; P < 0.001) and the presence of emphysema (OR, 2.95; 95% CI, 1.73 - 5.04; P < 0.001). CONCLUSION Lesion depth from the pleural surface and the presence of emphysema were strongly correlated with the increasing incidence of pneumothorax after CT-guided PCNB. Our results may be applicable for the risk management of PCNBs to reduce pneumothorax as a complication.