Purpose: Several studies have found an association between peripheral inflammatory cells and outcome. However, no study has explored their impact specifically in elderly patients. We have retrospectively examined pretreatment peripheral neutrophil/lymphocyte ratio (NLR), platelet/lymphocyte ratio (PLR), lymphocyte/monocyte ratio (LMR), and neutrophil/monocyte ratio (NMR) in 113 elderly breast cancer patients and correlated our findings with disease-free survival (DFS) and overall survival (OS).
Methods: All patients ≥ 65 years diagnosed from 2004 to 2018 with locally advanced breast cancer were included and classified as high vs low NLR, PLR, LMR, and NMR based on previously identified cutoffs. Estimated 1-, 3-, and 5-year DFS and OS were compared by Chi square analysis.
Results: Among 104 evaluable patients, only PLR was significantly associated with estimated 3-year DFS (85.1% vs 63.6%; P = 0.04) and OS (89.3% vs 68.1%; P = 0.03). Among 69 patients with three or more years of follow-up, PLR (P = 0.05), absolute lymphocyte count (ALC) (P = 0.01), polychemotherapy (P = 0.04), number of comorbidities (P = 0.02), polypharmacy (P = 0.005), and clinical stage (P = 0.03) were associated with 3-year DFS. Polypharmacy (OR 4.9; P = 0.02) and ALC (OR 4.6; P = 0.04) retained their significance in the multivariate analysis.
Conclusions: We have found an association between low PLR and longer DFS in elderly breast cancer patients that is in line with findings in patients with a wider range of ages. Our findings on NLR contrast with those of other studies, indicating a potential differential effect in elderly patients. In addition, the effect of polypharmacy on outcome in elderly patients warrants further investigation.
Keywords: Breast cancer; Elderly; Neutrophil-to-lymphocyte ratio; Platelet-to-lymphocyte ratio; Polypharmacy.