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Abstract
Introduction. the optimal treatment line for cyclin-dependent kinase 4/6 (CDK4/6) inhibitors in patients with hormone receptor-positive (HR+), HER2-negative breast cancer (BC).
Aim. To compare the efficacy of CDK4/6 inhibitor therapy when administered as first-line versus second-line treatment in patients with HR+, HER2-negative BC.
Materials and Methods. The study analyzed data from 163 patients with various disease stages and metastatic sites. Patients were stratified into two groups: those receiving CDK4/6 inhibitors as first-line therapy (n = 116) and those receiving them in subsequent lines (n = 47).
Results. First-line combination therapy with CDK4/6 inhibitors and aromatase inhibitors was associated with a significantly higher rate of partial responses (31.5 vs. 15.4%, p = 0.034). In contrast, second-line and subsequent use was associated with a significantly higher rate of disease stabilization (53.8 vs. 35.2%, p = 0.036).
Conclusion. The use of CDK4/6 inhibitors in combination with endocrine therapy is a reasonable strategy for both first-line and second-line treatment of HR+, HER2-negative BC.
References
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