Predicting recurrence and metastasis in thyroid cancer using the neutrophil- lymphocyte ratio: an accessible and innovative biomarker.

Abstract

Introduction: Thyroid carcinoma is usually indolent, although it exhibits marked biological variability. Up to 30% of cases may develop occult metastases, complicating preoperative stratification and limiting advance surgical and therapeutic decision-making. Traditionally, risk classification depends on the postoperative histopathological report, which delays the identification of aggressive tumors. In this context, the neutrophil-lymphocyte ratio (NLR), derived from a complete blood count, reflects systemic inflammatory status and immune response. Its preoperative evaluation could help identify patients at higher risk of recurrence and metastasis, especially in resource-limited settings. Objective: To determine the predictive capacity of preoperative NLR for recurrence and metastasis in adult patients with thyroid carcinoma treated at the head and neck unit of the La Trinidad Teaching Medical Center between January 2024 and January 2025, to associate NLR with clinical-pathological factors, TNM stages, and ATA risk categories, evaluating its viability as a complementary clinical tool. Methodology: Observational, two-stage cohort study in 26 patients ≥18 years of age with confirmed diagnosis and surgical treatment. Statistical analysis included hypothesis testing, correlations, and logistic regression. The sample showed a predominance of females and a mean age of 45.5 years. The mean NLR was 1.68. A significant association was found between NLR ≥2 and regional metastasis, as well as with advanced TNM stages. A recurrence was documented in a patient with an NLR of 5.13. Conclusion: Preoperative NLR showed potential as an accessible biomarker for improving risk stratification and optimizing clinical decisions in thyroid carcinoma, especially in resource-limited settings.