Epidemiology and Gender Variation in Thyroid Malignancies: A Retrospective Study of a Tertiary Care Center

Abstract Background: Thyroid malignancies are among the most common endocrine cancers, ranking ninth in incidence. In Saudi Arabia, thyroid cancer rates have significantly increased in both genders. Despite the rising incidence, mortality rates have declined. The evolving epidemiology of thyroid malignancies in Saudi Arabia reflects changes in demographics, culture, and clinical practices. This study aims to update the epidemiological data and examine gender variations in thyroid malignancies. Materials and Methods: This retrospective study included cases admitted to an academic tertiary care center from January 2023 to June 2024. Data on demographic variables (gender, age, and nationality) and clinical diagnosis categories (ranging from nondiagnostic to malignant) were collected. Histopathological details of thyroid lesions were also recorded. Clinical, cytological, and histopathological data were as per the Bethesda system, and they were analyzed accordingly. Results: The average age of 300 patients in our study cohort was 45.56 years, with 81.3% of them being female. The majority of patients were Saudi nationals (87.7%). According to the Bethesda system, the most common findings for lesions were benign (category II), followed by malignant (category VI) and atypia of undetermined significance (AUS; category III). Histopathologically, 52.7% showed benign features, with hyperplastic thyroid lesions (20.7%) and follicular adenomas (14.3%) being the most common. The most common malignancy was papillary carcinoma (42.7%). Age-specific analysis revealed differences, with younger patients more likely to have follicular neoplasm/suspicious for follicular neoplasm (category IV) and older patients having a higher risk of malignancy. Other variables including colloid cyst, subacute granulomatous thyroiditis, follicular carcinoma, Hürthle cell type, and medullary carcinoma were not statistically associated with any age group. Conclusion: Our findings are consistent with global trends indicating a significant increase in thyroid cancers, particularly among women. In our cohort, female patients were diagnosed with thyroid cancer nearly four times more frequently than male patients, which is double the commonly reported gender gap. There were statistically significant differences between genders in age groups, malignancies, and histopathological findings, with hyperplastic thyroid lesions and papillary carcinoma being more common in women. We also observed age-related differences in thyroid findings, with younger patients having more follicular neoplasms and older patients having more AUS.