The Role of Preoperative Radiological, Cytological, and Systemic Inflammatory Markers in Predicting Incidental Papillary Microcarcinoma in Patients with Multinodular Goiter: A Retrospective Single-Center Study.

Objective: Preoperative prediction of incidental papillary thyroid microcarcinoma (PTMC) in patients undergoing surgery for multinodular goiter (MNG) is a clinically significant challenge. This study aimed to evaluate the association of preoperative radiological (TI-RADS), cytological (Bethesda), and systemic inflammatory markers (neutrophil/lymphocyte ratio [NLR] and systemic immune-inflammation index [SII]) with incidental PTMC. Methods: This retrospective study included patients who underwent total thyroidectomy due to multinodular goiter. Preoperative ultrasonography findings (TI-RADS), fine needle aspiration biopsy results (Bethesda), and inflammatory markers (NLR and SII) were analyzed. Patients were grouped according to the presence of PTMC based on postoperative pathology results. Independent associations with PTMC were evaluated using multivariable binary logistic regression analysis with TI-RADS and Bethesda classifications entered as categorical variables. Results: A total of 283 patients who underwent total thyroidectomy for multinodular goiter were included in the study. The mean age was 52.75 ± 11.39 years, and 78.1% of the patients were female. Postoperative histopathological examination revealed incidental papillary thyroid microcarcinoma (PTMC) in 67 patients (23.6%). PTMC was detected in 67 patients (23.6%). In multivariable binary logistic regression analysis, high-risk TI-RADS categories (TR4-5 vs. TR1-3) and Bethesda III-IV categories (vs. Bethesda I-II) were independently associated with PTMC, whereas NLR and SII were not independently significant. Conclusions: High-risk TI-RADS and Bethesda categories were independently associated with incidental PTMC in patients with multinodular goiter, whereas inflammatory markers including NLR and SII were not independent predictors. Radiological and cytological evaluation appear to remain the primary components of preoperative assessment in incidental PTMC.