Nomogram model to predict pneumothorax after computed tomography-guided coaxial core needle lung biopsy

Purpose: To develop a predictive model to determine risk factors of pneumothorax in patients undergoing the computed tomography (CT)1-guided coaxial core needle lung biopsy (CCNB). Methods: A total of 489 patients who underwent CCNBs with an 18-gauge coaxial core needle were retrospectively included. Patient characteristics, primary pulmonary disease, target lesion image characteristics and biopsy-related variables were evaluated as potential risk factors of pneumothorax which was determined on the chest X-ray and CT scans. Univariate and multivariate logistic regressions were used to identify the independent risk factors of pneumothorax and establish the predictive model, which was presented in the form of a nomogram. The discrimination and calibration of the model were evaluated as well. Results: The incidence of pneumothorax was 32.91 % and 31.42 % in the development and validation groups, respectively. Age, emphysema, pleural thickening, lesion location, lobulation sign, and size grade were identified independent risk factors of pneumothorax at the multivariate logistic regression model. The forming model produced an area under the curve of 0.718 (95 % CI = 0.660-0.776) and 0.722 (95 % CI = 0.638-0.805) in development and validation group, respectively. The calibration curve showed good agreement between predicted and actual probability. Conclusions: The predictive model for pneumothorax after CCNBs had good discrimination and calibration, which could help in clinical practice.