Comparison of thyroid fine needle aspiration cytology results before and during the COVID-19 pandemic: the impact of the pandemic

Purpose: The aim of this study was to compare the Bethesda classification to report the distribution of thyroid cytology diagnostic categories and total thyroid fine needle aspiration cytology numbers before and during the pandemic. 
Materials and Methods: This study was planned in two phases: (1) before the pandemic, from March 15, 2018, and 29 February 2020, and during the pandemic period, from 1 March 2020 to 12 March 2022. Each period consisted of 24 months. The total number of thyroid fine needle aspiration cytology performed before the pandemic and during the pandemic dates and histopathological data were obtained from the hospital database. 
Results: 432 thyroid fine needle aspiration biopsies were performed in the pre-pandemic period and 351 during the pandemic. There was no significant difference considering age and gender in patients who underwent thyroid fine needle aspiration cytology before and during the pandemic. According to the Bethesda classification, those who were benign were 70.8% (n:306) and 59.0% (n:207) respectively before pandemia and during the pandemia. According to the Bethesda classification, malignant lesions were 4.4%(n:19), and 9.1%(n:32) before and during the pandemia, respectively. During the pandemic, malignant lesions were detected significantly more than before the pandemic. 
Conclusion: Malignant lesions were detected significantly more in the thyroid fine needle aspiration cytology results according to the Bethesda classification during the pandemic period compared to before the pandemic period.