DOI: 10.32322/jhsm.2020735 ISSN: 2636-8579

Predictive value of preoperative Systemic Immune-Inflammation (SII) Index and Prognostic Nutritional Index (PNI) in differentiated thyroid cancer: a retrospective analysis

Orhan Aslan, Ramazan Topçu, Mahmut Arif Yüksek, Mehmet Oğuzhan Polat, Aşkın Kadir Perçem, Mustafa Şahin, Havva Hande Keser Şahin
Show PDF Cite
Aims: Differentiating between benign and malignant thyroid nodules preoperatively is of critical clinical importance. This study aims to evaluate the effectiveness of the Systemic Immune-Inflammation Index (SII) and the Prognostic Nutritional Index (PNI), derived from routine laboratory tests, in the differential diagnosis of thyroid nodules.Methods: A retrospective analysis was conducted on 345 patients (215 benign, 130 malignant) who underwent surgery at a university hospital’s general surgery clinic between 2015 and 2025 and had definitive histopathological diagnoses. SII and PNI values were calculated from preoperative blood parameters. Group comparisons, bias-reduced logistic regression, and receiver operating characteristic (ROC) analysis were utilized to assess diagnostic performance.Results: No, statistically significant differences were found between the benign and malignant groups regarding SII (p=0.728) or PNI (p=0.299). After adjusting for age, gender, comorbidities, and histologic thyroiditis in logistic regression models, Neither Index showed a significant association with malignancy. ROC analysis demonstrated near-chance discriminatory ability for both SII (AUC: 0.511) and PNI (AUC: 0.467), indicating that these markers lack sufficient diagnostic accuracy.Conclusion: In this surgical cohort, preoperative SII and PNI showed no detectable stand-alone discrimination between benign and malignant thyroid pathology; whether they add value to ultrasonography and cytology remains to be tested.

More from our Archive