A New Diagnostic Approach Using the <scp>NLR</scp> / <scp>LMR</scp> Ratio in the Differential Diagnosis of Neck Masses: Hematologic Evaluation of Patients With Cervical Lymphadenopathy

OBJECTIVE: To evaluate the diagnostic utility of hematologic ratios derived from routine complete blood count parameters in differentiating malignant, granulomatous, and reactive cervical lymphadenopathies, with a particular focus on the novel neutrophil-to-lymphocyte ratio to lymphocyte-to-monocyte ratio (NLR/LMR). METHODS: This retrospective study included 406 adult patients who underwent excisional cervical lymph node biopsy between 2015 and 2024 and had histopathologically confirmed diagnoses. Patients were classified into five groups: reactive lymphadenopathy, Hodgkin lymphoma (HL), non-Hodgkin lymphoma (NHL), granulomatous non-caseating (Gran-NC), and granulomatous caseating (Gran-C). Pre-biopsy hematologic parameters (WBC, neutrophil, lymphocyte, monocyte, platelet, RDW) and derived ratios (NLR, LMR, PLR, RDW/PLT, NLR/LMR) were compared among groups. ROC curve analyses were used to assess the diagnostic performance of these parameters in distinguishing lymphoma from non-lymphoma cases. RESULTS: WBC, neutrophil, monocyte, and RDW levels were significantly higher in lymphoma groups than in reactive and granulomatous groups (p < 0.001). Among derived ratios, NLR, LMR, PLR, and NLR/LMR demonstrated significant intergroup differences (p < 0.001). ROC analysis identified NLR (AUC = 0.702, cut-off = 2.02, OR = 4.92) and NLR/LMR (AUC = 0.707, cut-off = 0.81, OR = 4.59) as the strongest discriminators for lymphoma. Multivariate logistic regression confirmed both NLR (OR = 1.49, 95% CI 1.24-1.79, p < 0.001) and NLR/LMR (OR = 1.94, 95% CI 1.46-2.57, p < 0.001) as independent predictors of malignancy. CONCLUSION: Simple hematologic ratios such as NLR and especially the combined index NLR/LMR can serve as reliable, low-cost, and noninvasive diagnostic indicators for differentiating lymphoma from benign lymphadenopathies. Incorporating these ratios.