Case report of severe pneumothorax due to lung cancer treated with anlotinib.

Anlotinib is a tyrosine kinase inhibitor that targets the vascular endothelial growth factor receptor for the treatment of lung cancer. Pneumothorax is a rare complication of anlotinib treatment. Here, the case of a male patient in his early seventies, with lung cancer combined with emphysema, who developed a pneumothorax during treatment with anlotinib, is described. The patient was admitted to hospital mainly for dyspnoea and was diagnosed with pneumothorax after digital radiography of the chest. The patient's symptoms improved significantly after closed chest drainage, and a repeat chest digital radiography showed a more resolved pneumothorax. The patient had no previous history of pneumothorax. After discontinuation of anlotinib, the latest follow-up chest computed tomography assessment in August 2023 showed no recurrence of pneumothorax, thus, the pneumothorax is presumed to have been associated with anlotinib in this patient. In addition, the authors speculate that emphysema may be a cause of pneumothorax in patients with lung cancer receiving anlotinib treatment. Therefore, clinicians should be alert to the risk of pneumothorax occurrence in patients with emphysema combined with lung cancer who are treated with anlotinib.