Effect of hysterectomy on risk of thyroid cancer and benign thyroid disorders in South Korean women

This study aimed to evaluate the association between hysterectomy and the risk of thyroid cancer and benign thyroid disorders in South Korean women. A retrospective cohort study was conducted using Korean National Insurance data from 2002 to 2020. Women aged 40 to 59 who underwent hysterectomy for benign conditions were matched with controls using propensity score matching. The participants were followed for a median of 11.4 years. Cox proportional hazards regression analyses were performed to assess the risk of thyroid conditions. Women who underwent hysterectomy showed a significantly higher risk of developing thyroid cancer (hazard ratio [HR] 1.351, 95% confidence interval [CI] 1.17-1.559) as well as increased incidence of goiter and non-toxic thyroid nodules. This elevated risk was observed across the age group 40-59 years and was independent of whether adnexal surgery was performed. No significant differences were found for other thyroid disease categories. These findings demonstrate an association between hysterectomy and increased risk of thyroid cancer. Further research is needed to elucidate the underlying mechanisms.