Application of Bethesda System for Reporting Thyroid Cytopathology in Correlation with Histopathological Diagnosis

Application of Bethesda System for Reporting Thyroid Cytopathology in Correlation with Histopathological Diagnosis
Alaa Hussam AL-Abidy ^1*, Aseel Abd Al-Zahra Alqzweni², Imad Hakim Al-HiLo³

^{1.M.B.CH.B, Candidate of the Arab Board of Medical Specialties, Department of Histopathology, Al-Sadr medical city, AL-Najaf, Iraq.
2.M.B.CH.B, F.I.C.M.S (path), Department of Histopathology, Al-Sadr medical City, Al-Najaf, Iraq.
3.M.B.CH.B, Advanced Oncology Program ( Medical Oncology), Faculty of Medicine, University Hospital of ULM, Baden- Württemberg, Germany.}

Background: The classification system for thyroid by Bethesda employs six categories, accompanied by management recommendations and rates of malignancy. Its efficacy has been validated by reference centers, who have compared expected malignancy rates with those of their respective populations. However, there is currently a lack of comparable studies conducted in Iraq.
Objectives: To evaluate the accuracy and Likelihood Ratio of FNA in diagnosis of patients with thyroid swellings by comparing Bethesda System for Reporting Thyroid Cytopathology (BSRTC) with histopathology.|
Methods: A retrospective study conducted in Al-Najaf-Iraq. Reports of 2050 fine-needle aspiration (FNA) for the period from June 2018 - June 2022 were reviewed and analyzed. Data of 220 patients who underwent surgery were compared to the cytohistological findings.
Results: The risk of malignancy in BSRTC in this study was as follow; DC I non-diagnostic or unsatisfactory (40.0%), DCII benign (19.6%), DC III atypia of undetermined significance / follicular of undetermined significance (0.0%), DC IV follicular neoplasm or suspicious for a follicular neoplasm (30.4%), DC V suspicious for malignancy (44.1%), DC VI malignancy (97.4%), the prevalence of malignancy and benign lesions in BSRTC was (40.5%) and (59.5%), respectively. The, sensitivity was (78.3%), specificity (64.9%), positive predicted value (61.9%), negative predicted value (80.4%), and accuracy was (71.6%).
Conclusion: The Bethesda System is good diagnostic tool in thyroid swellings and can be applied to the Iraqi population, since the diagnostic values and Likelihood ratio were closely to other results in many different literatures and within reference ranges.