Microwave Ablation of Benign Thyroid Nodules: Effects on Systemic Inflammatory Response.

Objective: To explore the alterations of neutrophil-to-lymphocyte ratio (NLR) as a systemic inflammatory marker after microwave ablation for benign thyroid nodules. Study Design: A descriptive study. Place and Duration of Study: Department of Radiology, Antalya Training and Research Hospital, from December 2018 to June 2019. Methodology: Demographic data of the patients, ultrasonographic features of the nodules, thyroid function tests of the patients, leukocyte, neutrophil, lymphocyte values, and thyroid nodule volumes of the patients before and after the procedure were recorded. NLR and volume reduction ratio (VRR %) of 35 patients with thyroid nodules were compared before and after microwave ablation therapy of the thyroid nodules. Results: The nodule volume decreased from 23.89 +/- 15.44 cc to 11.57 +/- 8.65 cc at two months and to 7.79 +/- 5.74 cc at six months. The VRR% increased from 38.65 +/- 16.82 to 63.16 +/- 14.19 at three months and to 68.29 +/- 11.80 at six months. The mean value of NLR decreased from 2.28 +/- 0.86 to 1.78 +/- 0.54. ROC curve analysis suggested that the optimum pre-NLR cut-off point for 50% VRR success was 2.50 with the specifity and sensitivity of 0.67 and 0.50. Conclusion: After ultrasound-guided microwave ablation of benign thyroid module, VRR percentage increased significantly, while the inflammatory marker NLR value decreased.