Palbociclib-Induced Pneumonitis: A Reported Case and Review of the Literature

The treatment of metastatic breast cancer has undergone significant changes in recent years. Palbociclib, a selective cyclin-dependent kinase 4/6 (CDK4/6) inhibitor, has become a cornerstone in the treatment of hormone receptor-positive, HER2-negative advanced breast cancer, in addition to endocrine therapy. While palbociclib is generally well-tolerated, pneumonitis has emerged as a rare but serious adverse effect. This article presents a case of palbociclib-induced pneumonitis leading to death, followed by a comprehensive review of the literature to outline the clinical features, diagnosis, and management strategies for this condition.