Neutrophil-to-Lymphocyte Ratio as a Factor Predicting Radiotherapy Induced Oral Mucositis in Head Neck Cancer Patients Treated with Radiotherapy

Background: The objective of this research conducted in head and neck cancer (HNC) patients was the assessment of the relationship between neutrophil-to-lymphocyte ratio (NLR) and the incidence of severe radiotherapy (RT) induced oral mucositis (OM), as well as overall survival (OS). Methods: The study involved 207 patients in advanced stages (III–IV) of HNC. RTOG/EORTC scale was used to assess OM. The pre-treatment NLR was specified as the absolute neutrophil count divided by the absolute lymphocyte count. Results: Starting from second to seventh week of RT, we observed a significant, positive correlation between NLR values and OM grade. From the second to seventh week of RT, higher NLR values were related with significant increases (from 2- to over 24-fold) in the risk of occurrence of more severe OM (multivariate analysis confirmed its independent influence). Moreover, multivariate analysis for survival revealed that both higher TNM stage (HR = 1.84; p = 0.0043) and higher NLR values (HR = 1.48; p = 0.0395) were independent prognostic factors. Conclusion: NLR is a simple and accurate parameter that is useful in the evaluation of the risk of more severe OM, as well as an independent prognostic factor of OS in patients subjected to RT due to HNC.