<i>Pneumocystis jirovecii</i> pneumonia in a patient with HR⁺/HER2^- advanced breast cancer following abemaciclib combined with endocrine therapy: A case report.

ABSTRACT: This case report presents the first occurrence of Pneumocystis jirovecii pneumonia in a patient with breast cancer during CDK4/6 inhibitor therapy. Abemaciclib serves as a first-line therapeutic option for hormone receptor-positive/human epidermal growth factor receptor 2-negative advanced breast cancer. However, there are no documented cases in the literature linking abemaciclib to Pneumocystis jirovecii pneumonia. Notably, although rare, abemaciclib-induced severe lymphopenia may predispose patients to potentially life-threatening opportunistic infections. Optimal patient management requires multidisciplinary collaboration and strict compliance with American Society of Clinical Oncology/European Society for Medical Oncology guidelines to optimize the balance between therape

SUBMITTER: Hao W 

PROVIDER: S-EPMC12434459 | biostudies-literature | 2025 Nov

REPOSITORIES: biostudies-literature