Most patients with PTMC demonstrate excellent clinical outcomes, and distant metastases rarely occur. However, distant metastasis of PTMC can be fatal. Performing a meticulous pathologic examination of metastatic LNs to identify the presence of extranodal extension and the pathologic subtype of metastatic LNs helps to assess the risk of a distant metastasis in patients with PTMC.

This first nationwide survey demonstrates more than adequate iodine intake and a right-shifted distribution of serum TSH levels in the Korean general population. Nutritional iodine status is important for determining serum TSH levels and is associated with a high prevalence of hypothyroidism. Nutritional iodine status might need to be considered when establishing TSH reference intervals of populations in iodine-replete areas.