Inflammatory markers related to survival in breast cancer patients: Peru.

Introduction: Breast cancer is a disease with high global prevalence. Clinical inflammatory biomarkers have been proposed as prognostic indicators in oncology. This research aims to determine the relationship between inflammatory markers and overall survival in breast cancer patients from four representative hospitals in Lima, Peru.

Methods: This is a multicentric, analytical, longitudinal retrospective cohort study with survival analysis in female patients with breast cancer, from 2015 to 2020, who had received at least one complete treatment regimen. The dependent variable was overall survival, and the independent variables were inflammatory markers neutrophil lymphocyte ratio, platelet lymphocyte ratio (PLR), albumin, and red cell distribution width; intervening variables included age, clinical stage, molecular subtype, and other known prognostic factors. The Kaplan-Meier method was applied to generate survival curves with the Log-Rank test, and finally, Cox regression, to find crude and adjusted hazard ratios (HR).

Results: Of 705 evaluated patients, 618 were analyzed. The mean age was 56.6 ± 12.3 years, 18.0% of patients were pure HER2 positive, 39.3% luminal A, 29.9% luminal B, 11.0% triple-negative, and 81.4% showed overweight and obesity. The average overall survival was 51.1 months. In the multivariate analysis, factors significantly related to lower overall survival were PLR > 150 (adjusted HR: 2.33; 95% confidence interval (CI): 1.22, 4.44) and stage III (adjusted HR: 4.15; 95% CI: 1.35, 12.83).

Conclusions: The Elevated Platelet-Lymphocyte Index and advanced clinical stage were associated with lower overall survival in breast cancer patients. Furthermore, PLR >150 proved to be an independent prognostic factor for mortality.