Assessment of the association between inflammatory markers and nodule characteristics in patients with thyroid nodules

Objective: Thyroid nodules are a common endocrine system pathology arising within the thyroid gland. This study aimed to evaluate the relationship between inflammatory biomarkers and the risk scoring system developed by the American College of Radiology (ACR) Thyroid Imaging Reporting and Data System (TIRADS) for thyroid nodule characterization. Materials and Methods: This retrospective study reviewed the demographic data, medical records, comorbid conditions, laboratory results, and ultrasound findings of patients who visited the Internal Medicine and Endocrinology and Metabolism outpatient clinics at Afyonkarahisar Health Sciences University Faculty of Medicine between June 1, 2018, andJune 5, 2024. A total of 411 individuals were included in the study. They were divided into two groups: patients with thyroid nodules group (n=290) and patients without thyroid nodules as controlgroup (n=121). Patients with thyroid nodules and control group were compared for levels of C-reactive protein (CRP), Platelet/Lymphocyte Ratio (PLR), Neutrophil/Lymphocyte Ratio (NLR), Lymphocyte/MonocyteRatio (LMR), Platelet/AlbuminRatio (PAR), CRP/AlbuminRatio (CAR), Systemic Inflammatory Index (SII) and Pan-Immune Inflammation Value (PIV). Subgroups within the thyroid nodules group were defined based on the ACR-TIRADS risk scoring system, and the relationship between nodule characteristics and inflammatory biomarkers was analyzed. In ourstudy, the ACRTIRADS scoring system classified the TR1 and TR2 groups as the low-risk category, in which thyroid fine-needle aspirationbiopsy (FNAB) was not required, and the TR3, TR4, and TR5 groups as the high-risk category, where FNAB was deemed necessary. The relationship between inflammatory parameters and the groups requiring or not requiring FNAB was analyzed. Results: A total of 411 cases, 327 femalesand 84 males, with 554 patients with thyroid nodules were included. The mean age was 43.02 ± 11.75 years in the patients with thyroid nodules group and 33.46 ± 9.69 years in the control group without thyroid nodules (19-65 years range). Significantly higher CRP and CAR levels were in the thyroid nodules group, compared to the control group (p = 0.005 and p = 0.011, respectively). In the ACR-TIRADS classification, thyroid nodules were categorized into low-risk and high-risk groups. There was no significant difference between the internal structure, echogenicity, shape, echogenic focus characteristics and inflammatory parameters in the thyroid nodule (p>0.05). NLR, SII and PID were statistically higher in the group with higher margin irregularity, compared to the group with lower margin irregularity (p<0.001, p<0.001, p=0.004, respectively). Higher vii margin irregularity positively correlated with NLR (r=0.25, p=0.001), SII (r=0.213, p=0.001), and PIV (r=2.61, p=0.011) levels. LMO level was significantly higher in the group where FNAB was recommended (≥3 points), compared to the group where FNAB was not recommended (<3 points) (p=0.026). LMO and PAO (p=0.04 and p=0.002, respectively) were significantly higher in the nodule with a width of ≥ 10 mm and above, compared to the nodule width below 10 mm group. PAO was significantly higher in the nodule with a length of ≥10 mm and above, compared to a nodule below 10 mm group (p=0.002). Conclusion: In our study, a significant relationship was found between the presence of thyroid nodule and CRP and CAO. According to ACR-TIRADS scoring, an increase in inflammatory parameters was observed in thyroid nodules with increased margin irregularity. As the malignancy risk score increases in thyroid nodules, the inflammatory markers in the nodule also increase. These findings show that there are significant relationships between some inflammatory biomarkers such as CRP, CAO, NLO, SII, PID, LMO, PAO and the presence and characteristics of thyroid nodules; emphasizes their potential role in assessing the risk of malignancy. Comprehensive studies need to be carried out to generalize the relationship between the characterization of sonographically detected thyroid nodules and inflammatory markers. Keywords: CRP, Systemic Immune Inflammatory Index, Pan Immune Inflammation Value, Thyroid Ultrasonography