Association of Neutrophil-to-Lymphocyte Ratio and Lymphocyte-to-Monocyte Ratio with Clinicopathological Features and Short-Term Outcome in Well-Differentiated Thyroid Cancer

Abstract

Purpose of the Study: To assess the association of inflammatory markers with known risk factors and short-term outcome of well-differentiated thyroid cancer. Materials and Methods: Well-differentiated nonmetastatic thyroid cancer patients diagnosed and treated between September 2015 and December 2019 at Kasturba Hospital, Manipal, India, were retrieved for the study. Patients’ presurgical blood parameters were noted, and neurtrophil-to-lymphocyte ratio (NLR) and lymphocyte-to-monocyte ratio (LMR) were calculated. Clinicopathological details along with tumor markers at baseline and at 6 months’ follow-up were tabulated. Patients were categorized as complete disease clearance if their clinical examination was normal, stimulated thyroglobulin (Tg) was <1 ng/ml, Anti-thyroglobulin antibodies <65 IU/L or showing a decreasing trend, and follow-up I-131 whole-body scan was negative. The association of the inflammatory markers with known risk factors and short-term outcomes were compared. Results: A total of 272 patients were analyzed in the study. The median NLR in our study cohort was 2.55 (mean = 3.96 with standard deviation [SD] =4.20) and the median LMR was 3.72 (mean = 3.79 with SD = 1.94). The disease clearance rate of our study cohort was 73.9%. The median NLR (2.4 vs. 3.1) and LMR (3.13 vs. 3.93) were significantly different among the patients with complete disease clearance and those with persistent disease (P = 0.008 and P = 0.003, respectively). The known risk factors such as multifocality (P = 0.04), tumor size (P = 0.013), lymph node metastases (P = 0.001), and baseline Tg (P ≤ 0.001) were significantly associated with persistent disease at 6 months. The NLR showed a positive correlation and LMR had a negative correlation with the known risk factors, however, the associations were not statistically significant. Conclusions: The NLR and LMR are simple yet potential prognostic tools in well-differentiated thyroid cancer.