Neutrophil/lymphocyte and platelet/lymphocyte ratio and outcome after first chemotherapy of patients with breast cancer in a city of Minas Gerais

Abstract

Aim. To evaluate the factors associated with the pre and post-first chemotherapy inflammatory response in cancer patients, by determining the neutrophil-to-lymphocyte ratio (NLR) and the platelet-to-lymphocyte ratio (PLR) in the breast cancer population in Barbacena, and to verify their contribution to the observed outcome. Methods. Retrospective study, including 152 breast cancer patients in a reference hospital in Barbacena, MG, between 2016 and 2021. The results of complete peripheral blood counts before any therapeutic procedure (baseline blood count - surgery, radiotherapy, or chemotherapy) were collected, as well as follow-up exams. Additionally, data regarding the outcome of the first treatment and/or date of disease progression or death were also collected. The NLR was obtained by the ratio of the absolute neutrophil count to the absolute lymphocyte count. The PLR was calculated by dividing the absolute number of platelets by the absolute number of lymphocytes. The median NLR and PLR were calculated, and the data were processed using JASP statistical software v. 16.4.0. Results. It was observed that both alterations in NLR and PLR were predictors of outcome, with patients showing higher NLR (p = 0.034) and PLR (p = 0.043) in the post-first cycle of treatment blood count for disease progression or death. The effect size for both relationships was 0.218. Conclusion. NLR and PLR are useful as predictors of post-first treatment outcome in breast cancer patients.