Published: 2022-02-21

Pneumonitis, a common adverse event of cyclin-dependent kinase 4/6 inhibitors: a case report

Fernanda E. Rivera-Sánchez, Carolina Moreno-Licea, Raúl Mellado-Orellana, Salvador González-Santiesteban, Roberto de la Peña-López


The cyclin-dependent kinase (CDK) 4/6 inhibitors are approved for women with hormone receptor-positive, human epidermal growth factor receptor 2-negative advanced breast cancer, these can develop common adverse events. We present the case of a woman diagnosed with metastatic hormone receptor-positive, HER2-negative breast cancer, who developed pneumonitis related to palbociclib. Pulmonary toxicity of CDK 4/6 inhibitors is not an uncommon adverse event that has been increasing in incidence.


CDK 4/6 inhibitors, Breast cancer, Pulmonary toxicity, Common adverse event

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