Work

Evaluating Ki-67 and PR as prognostic indicators in CDK4/6 inhibitor treatment for metastatic breast cancer

Year: 2025

Type: article

Abstract: Background: The treatment of choice as the first line for patients with metastatic breast cancer (MBC) who are hormone receptor-positive (HR+)/HER2-negative (HER2-) is the combination of endocrine therapy (ET) with cyclin-dependent kinase 4/6 inhibitors (CDK4/6i). Identifying prognostic or predictive factors of response could have important clinical implications. This study analysed the prognostic value of Ki-67 and progesterone receptor (PR) expression on progression-free survival (PFS) in this population. Methods: A retrospective cohort study was conducted in patients with HR+/HER2- MBC, who had received first-line treatment with CDK4/6i combined with ET. For the PFS analysis, the log-rank test was used and for the multivariate analysis, a Cox regression analysis was performed. Results: = 0.041) in patients with PR >20%. Conclusion: Patients with PR values <20% tended to have shorter PFS, unlike the Ki-67 value, which did not demonstrate an impact on PFS. This suggests a prognostic value of PR expression levels in this scenario.

Source: ecancermedicalscience

DOI: 10.3332/ecancer.2025.1963