About one-third of differentiated thyroid cancer patients need levothyroxine (LT4) therapy within 3 years following hemithyroidectomy when postoperative thyroid stimulating hormone (TSH) levels of up to 4 mIU/L are considered acceptable, according to study results published in the European Thyroid Journal. Hemithyroidectomy is increasingly used for low-risk differentiated thyroid cancer (DTC), but guidelines recommend initiating LT4 when postoperative TSH exceeds 2 mIU/L to prevent TSH-mediated growth. In this retrospective cohort study, researchers aimed to assess how many low-risk DTC patients maintain normal thyroid function 3 years post-hemithyroidectomy when postoperative TSH levels increased to a maximum of 4 mIU/L. This study included 162 patients diagnosed with thyroid cancer and treated with hemithyroidectomy from the national Danish Thyroid Cancer Database (DATHYRCA) between July 2016 and July 2020. The researchers compiled and reviewed data on LT4 treatment initiation, DTC recurrence, remnant lobe nodularity, patients’ hospital charts, and pre- and postoperative TSH.