Clinical significance of neutrophil-to-lymphocyte ratio, lymphocyte-to-monocyte ratio, platelet-to-lymphocyte ratio and prognostic nutritional index in low-risk differentiated thyroid carcinoma.

Objective: Inflammation and nutritional status play an important role in the prognosis of cancer. Lymphocyte-to monocyte ratio (LMR), neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR) and prognostic nutritional index (PNI) are independent prognostic scores in numerous cancers. However, any study showed their prognostic role in low-risk differentiated thyroid carcinoma (DTC). We aimed to clarify and identify the prognostic value of inflammation indices in low-risk DTC patients.

Methods: We analysed data from 116 patients, dividing the population into two groups, according to AJCC staging system (8th edition). The LMR, NLR, PLR and PNI cut-off value were determined using receiver operating characteristic (ROC) curve. Disease-free survival (DFS) was calculated with Kaplan-Meyer and Log-Rank tests and the risk of recurrence was calculated with univariate and multivariate Cox regression. Statistical significance was p < 0.05.

Results: We found a baseline NLR value ≥ 1.750 (75% sensitivity, 40.2% specificity) and a baseline LMR value of 3.83 (66.7% sensitivity, 48.9% specificity). Overall DFS was 74.995 ± 3.236 with a p value of 0.678. NLR showed a hazard ratio for recurrence with almost twice the risk of recurrence (Adjusted Hazard Ratio /HRA): 1.828, p-value = 0.019).

Conclusions: NLR can be considered a prognostic score with twice the risk of recurrence in low-risk DTC patients with NLR < 1.750.