Abstract
A 52-year-old man with a past medical history of chronic myeloid leukemia (CML) in remission developed progressive shortness of breath over a two-month period. He was initially treated with dasatinib for four years, until developing pulmonary arterial hypertension (PAH) with pleural effusions. His symptoms improved after stopping dasatinib. He was then switched to bosutinib for approximately one year, which was then stopped before admission due to worsening shortness of breath. His initial workup showed bilateral pleural effusions with severe PAH and cor pulmonale. He had symptomatic improvement with PAH-specific therapy following discontinuation of the bosutinib. The life expectancy of CML patients has increased in the era of the tyrosine kinase inhibitors (TKIs), and managing adverse events (AEs) of the TKIs and improving quality of life are becoming more important. Pulmonary hypertension (PH) and pleural effusions are rarely reported AEs of bosutinib. More reports with PH and pleural effusions arising after bosutinib use in patients previously treated with dasatinib is furthermore concerning. In this era with novel chemotherapeutic agents, physicians ought to be weary of the significant morbidity implicated by these agents in the lives of patients.