Abstract
Dasatinib, a second-generation tyrosine kinase inhibitor, is highly effective in chronic myeloid leukaemia (CML) but is associated with pleural complications in approximately 28%-37% of patients. We report four patients with CML who developed dasatinib-induced pleural effusion after prolonged treatment (2-10 years), including one case of chylothorax. All presented with dyspnea, and imaging with diagnostic thoracentesis confirmed exudative pleural effusions. One patient demonstrated triglyceride-rich fluid consistent with chylothorax. Dose reduction of dasatinib to 50 mg/day led to complete clinical and radiological resolution in three patients while maintaining molecular remission. The fourth patient encountered recurrent chylothorax despite dosage modification and supportive therapy, necessitating permanent discontinuation of dasatinib and transition to nilotinib, resulting in sustained radiological resolution and continued molecular response. This case series highlights the spectrum of late-onset dasatinib-related pleural complications and demonstrates that timely dose modification or TKI switching can effectively manage toxicity while preserving oncological outcomes.