Background: We present two cases of secondary pneumothorax after immunotherapy in two different clinics. Case summary: A 25-year old female patient with metastatic osteosarcoma, treated with atezolizumab. Grade 2 pneumonitis developed twice in the first year. Treatment was continued after recovery and areas of pneumonitis and pneumothorax were observed on computed tomography. No other reason could be found to cause pneumothorax. Pneumothorax resorbed spontaneously during follow-up. A 36-year old female patient treated with nivolumab for metastatic renal cell carcinoma (RCC), areas of pneumonitis and pneumothorax were only found as the cause of dyspnea. After treatment, remission was achieved on computed tomography findings. Pneumothorax was detected for the second time during continued therapy, and immunotherapy stopped permanently. Conclusion: These cases, indicate that immunotherapy can cause secondary immune-related pneumothorax based on immune pneumonitis.
Keywords: atezolizumab; immune-check point inhibitors; immune-related pneumonitis; immunotherapy; nivolumab; secondary pneumothorax.
Lay abstract Immune checkpoint inhibitors are used with increasing frequency in cancer therapy. New side effects associated with these drugs have been identified. Air accumulation between the pleural membranes, which envelop the lungs and protect them in the ventilation function, without trauma may occur after using these drugs. We present here two cases that were treated with these drugs and developed this side effect. Patients with newly developed shortness of breath during this treatment should be careful about side effects such as this.