ABSTRACT
Objective: This research aim was to evaluates the role of the pre-ablation neutrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) as predictors of distant metastases in patients with differentiated thyroid cancer (DTC). Methods: A retrospective analysis was given to 140 patients with DTC who received 131I remnant ablation after surgery. The patients were divided into two groups based on the existence of distant metastasis. Results: The two groups showed no significant difference in age, gender, WBCs, neutrophils, monocytes, eosinophils, basophils and whether the tumor was multifocal. In the univariate analysis, significant differences were found in tumor size (p=0.021), lymphocyte (p=0.012), NLR (p=0.027), and LMR (p=0.007). According to the ROC curves, NLR had an AUC of 0.612 ± 0.097 with a cut-off value of 1.845, sensitivity of 60.0%, and specificity of 66.2% (p=0.027). LMR had an AUC of 0.638 ± 0.095 with a cut-off value of 4.630, sensitivity of 84.6%, and specificity of 35.4% (p=0.007). In the multivariate analysis, larger tumor size (OR=5.246, 95% CI 1.269-10.907, p=0.009) and higher NLR (OR=2.087, 95% CI 0.977-4.459, p=0.034) were statistically significant for distant metastases. Conclusion: This research reveals that pre-ablation NLR and tumor size are significantly statistically correlated with distant metastases in patients with DTC.