Resumen de Retrospective registry of patients with locally advanced/metastatic HR+/HER2− breast cancer treated in clinical practice in Andalusia
Natalia Chavarría Piudo, Isabel Blancas López-Barajas, E. González Flores, F. Henao Carrasco, Pilar López Álvarez, David Morales Pancorbo, Salvador Gámez Casado, María de la Cabeza Lomas Garrido, José Manuel Rodríguez García, Antonia Martínez Guisado, Adrián Sánchez Vegas, M. Ruiz Borrego
Background Limited data are available regarding the real-world efectiveness and safety of Cyclin Dependent Kinase 4/6 inhibitor (CDK4/6i) (palbociclib/ribociclib) just as a frst-line treatment for patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2‒) metastatic breast cancer (MBC).
Objective To assess whether clinical or demographic characteristics limit access to frst-line CDK4/6i treatment in clinical practice in the Autonomous Community of Andalusia (Spain) between November 2017 and April 2020. In addition, efectiveness will be described in an exploratory analysis.
Methods Physicians from 12 centers participated in selecting demographic and clinical characteristics, treatment, and outcome data from women with HR+/HER2- MBC treated with or without CDK4/6i in addition to hormonal in the frst-line setting, in a 3:1 proportion. Kaplan–Meier analysis estimated progression-free rates (PFRs) and survival rates (SRs).
Results A total of 212 patients were included, of whom 175 (82.5%) were in the CDK4/6i treatment group and 37 (17.5%) were in the non-CDK4/6i treatment group (control group). Patients in the CDK 4/6i treatment group were younger (p=0.0011), the biopsies of the metastatic site at the moment of the relapse were most commonly performed (p=0.0454), and had multiple metastatic sites (p=0.0025). The clinical beneft rate (CBR) was 82.3% in the CDK4/6i group and 67.8% in the control group. Median time to a progression event or death (PFS) was 20.4 months (95%CI 15.6–28) in the CDK4/6i group and 12.1 months (95%CI 7.9–not reached) in the control group.
Conclusions Younger patients, biopsies of metastatic disease and with multiple metastatic sites were more frequently treated with CDK4/6i in our daily clinical practice.
