Real-life data of palbociclib with endocrine therapy in HR positive HER2- negative advanced breast cancer ; Analyse de données de vie réelle sur l’utilisation du palbociclib combiné à l’hormonothérapie dans le cancer du sein métastatique RH+/HER2-

Introduction: Cyclin-dependent kinase 4/6 (CDK4/6) inhibitors are the treatment in hormone receptor positive (HR+) and HER2 positive (HER2+) locally advanced or metastatic breast cancer (ABC/MBC) in combination with endocrine therapy (ET). Palbociclib was the first CDK4/6 inhibitor approved in Europe for use in combination with aromatase inhibitors in the first line setting, or with an anti-estrogen, fulvestrant, after progression on ET. The objective of this study was to analyze real-life data regarding the efficacy, predictive factors, and the safety of palbociclib.Material and methods: A retrospective unicentric study was conducted from January 2016 to January 2019. Clinical, biological, and radiological data of patients treated with palbociclib for HR+/HER2- ABC/MBC were collected. Survival data and predictive factors of response were also analyzed.Results: 191 patients were included in the study. Palbociclib therapy was prescribed in first line in 83 patients (43.5%), in 2nd or 3rd line in 59 patients (30.9%) and after 3 lines in 49 patients (25.6%). The median follow-up was 36 months. Progression-free survival (PFS) and overall survival (OS) in the global population were 12 months (95% CI [9-17]) and 39 months (95% CI [35-NA]) respectively. In multivariate analysis, several factors were identified as poor prognostic factors for PFS: a high neutrophil/lymphocyte ratio, elevated CEA or CA 15-3 levels at palbociclib initiation, and a history of ET in ABC/MBC setting. High Allred score for estrogen receptor and palbociclib dose reduction during treatment were predictive for better PFS. Thetoxicity profile was similar to published data.Conclusion: These real-life data are consistent with previously published pivotal and real-life studies. Dose reduction of palbociclib does not impact the benefit of treatment and might be a good predictive factor of response. ; Introduction : Les inhibiteurs de CDK4/6 sont indiqués en association avec l’hormonothérapie pour le traitement des cancers du sein localement avancés ...