A Comparative Study: The Bethesda System and Italian System for Reporting Thyroid Cytopathology with Histopathological Correlation

Background: Thyroid nodules are considered common clinical findings that have a malignant evolution of 5% to 20%. The present study will try to compare the diagnostic effectiveness between the Bethesda System for Reporting Thyroid Cytopathology and the Italian Classification System on the diagnosis of thyroid nodules, considering the sensitivity, specificity, and overall diagnostic accuracy. Methods: This prospective analytic study was conducted at Pt. Jawahar Lal Nehru Memorial Medical College, Raipur, Chhattisgarh, between September 2022 and September 2024. Sixty-two patients with palpable thyroid nodules who underwent FNAC were included in the study. The results were classified cytologically based on the Bethesda System and the Italian Classification for cytohistological correlation. Results: Out of 62 patients, 25 were males and 37 were females. Maximum prevalence was found in the age group of 31-40 years, which accounted for 33.9%. Mainly, it was revealed that the majority of them were benign. Thus, Bethesda Category II had 54.8% and Italian TIR 2 – 56.5%. Generally, a good correlation was obtained between the two systems: 94.3% for benign, and 100% for the malignant categories. The Bethesda system was sensitive to 92% and specific to 88% cases to detect malignant cases and had a better performance in diagnosing the benign lesions (PPV: 78%, NPV: 95%). However, compared with the latter, the Italian system had a higher sensitivity of 96% to detect malignant cases, along with specificity of 84% (PPV: 82%, NPV: 97%). Conclusion: Both the Bethesda and the Italian systems are very effective in the classification of thyroid nodules, with a significant concordance between them. The Italian system performed really very well in the diagnosis of malignant lesions. Standardized reporting allows more accurate diagnoses, enabling better management of the patient. Larger studies will also be required to confirm such findings for further refinement of diagnostic criteria.