Predictive Value of Lymphocyte-Related Blood Parameters at the Time Point of Lymphocyte Nadir During Radiotherapy in Breast Cancer

Purpose: Various reports found a relationship between lymphocyte-related blood parameters (LRBP), including absolute lymphocyte counts (ALC), neutrophil-to-lymphocyte ratio (NLR), and platelet-to-lymphocyte ratio (PLR) and prognosis of breast cancer. Most of the studies focused on LRBP pre-treatment. Seldom have studies focused on LRBP during radiotherapy. We intended to perform a retrospective cohort study on the prognostic value of LRBP at the time point of lowest ALC during radiotherapy for breast cancer. Patients and methods: A total of 158 female patients were included in radiotherapy group because of the strict limitation standards of complete routine blood test results at pre-treatment and pre-operation, and at least once a week during radiotherapy. Besides 221 patients, including the 158 patients of radiotherapy group, were adopted in pre-treatment group and pre-operation group. Results: ALC and PLR at the time point of lowest ALC during radiotherapy are prognostic predictors of breast cancer, and lower ALC and higher PLR are independent significant predictors of poor DFS. Besides, lower ALC, higher NLR and higher PLR at both pretreatment and pre-operation were found to be independent variables for predicting poor DFS. Conclusion: LRBP at pre-treatment, pre-operation, and during radiotherapy may serve as predictors of outcomes of breast cancer.