Pneumothorax, pleural effusion, and chest tube placement after radiofrequency ablation of lung tumors: Incidence and risk factors

Purpose: To retrospectively evaluate the incidence of and risk factors for pneumothorax, pleural effusion, and chest tube placement for pneumothorax after radiofrequency (RF) ablation of lung tumors. Materials and Methods: Institutional review board approval was obtained, with waiver of informed consent. This retrospective study comprised 224 ablation sessions for 392 tumors in 142 patients (92 men, 50 women; mean age, 64.0 years). Multiple variables were analyzed by using the Student t test or the Mann-Whitney U test for numerical values and by using the χ² test or the Fisher exact test for categorical values in order to assess risk factors for pneumothorax, pleural effusion, and chest tube placement for pneumothorax. Results: The incidence of pneumothorax, pleural effusion, and chest tube placement for pneumothorax was 52% (117 of 224 sessions), 19% (42 of 224 sessions), and 21% (24 of 117 sessions), respectively. For pneumothorax, risk factors included male sex (P = .030), no history of pulmonary surgery (P < .001), a greater number of tumors ablated (P < .001), involvement of the middle or lower lobe (P = .008), and increased length of the aerated lung traversed by the electrode (P = .014). For pleural effusion, risk factors included the use of a cluster electrode (P = .008), decreased distance to the nearest pleura (P = .040), and decreased length of the aerated lung traversed by the electrode (P = .019). For chest tube placement for pneumothorax, risk factors included no history of pulmonary surgery (P = .002), the use of a cluster electrode (P < .001), and involvement of the upper lobe (P < .001). Conclusion: Pneumothorax and pleural effusion can occur after RF ablation in patients with lung tumors, and chest tube placement for pneumothorax is sometimes required.