Search for nutritional and inflammatory marker ratios to predict neutropenia in FEC therapy for breast cancer: A retrospective observational study.

OBJECTIVE: Nutritional and inflammatory marker ratios are known to predict response to chemotherapy in breast cancer, but whether they predict adverse effects caused by chemotherapy remains unclear. We investigated whether nutritional and inflammatory marker ratios before starting FEC therapy (5-fluorouracil, epirubicin, and cyclophosphamide) predict grade 4 neutropenia as a serious adverse effect. MATERIALS AND METHODS: 61 patients with breast cancer who started FEC therapy for the first time as preoperative or postoperative chemotherapy were studied. Relevant nutritional and inflammatory marker ratios were compared between patients who developed grade 4 neutropenia (n = 44) and those who did not (n = 17). RESULTS: In univariate analysis, occurrence of neutropenia was related significantly (p < 0.05) to pre-FEC-therapy white blood cell count, platelet count, neutrophil count, lymphocyte-to-monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), and modified Glasgow prognostic score. Analysis using cutoff values obtained from receiver operating characteristic curves showed that LMR, NLR, and PLR predicted grade 4 neutropenia. However, multivariate logistic regression analysis identified no independent factor associated with grade 4 neutropenia. A post-hoc power analysis revealed an inadequate sample size. CONCLUSION: Inflammatory marker ratios, especially PLR, may predict grade 4 neutropenia caused by FEC therapy for breast cancer. Although multivariate analysis identified no independent predictive markers in this study due to inadequate sample size, further prospective large-scale research is needed to examine the usefulness of nutritional and inflammatory marker ratios for predicting adverse effects.