A Young Patient with Intrathyroidal Papillary Thyroid Cancer and Family History of Differentiated Thyroid Cancer

Up to 10% of all nonmedullary thyroid cancers (NMTCs) are familial. Until now, the diagnosis is clinical: when three or more first-degree relatives are affected, the probability that the cancers are not sporadic exceeds 90%. Some small studies have linked familial NMTCs (FNMTCs) with higher rates of multifocal involvement, lymph node metastases, and recurrence, as well as lower disease-free survival, but others have found no evidence of increased aggressiveness. Management should thus be based on the actual ATA risk classification. The 2015 ATA guidelines list familial disease as a possible indication for thyroidectomy instead of lobectomy but make no recommendation for or against the use of radioiodine remnant ablation (RRA), noting that there is no evidence that it improves disease-specific or disease-free survival of patients with low-risk NMTCs. The guidelines also refrain from recommending for or against ultrasound-based screening of family members: although it may allow earlier diagnosis of thyroid cancer in these individuals, the current evidence does not demonstrate any effect on morbidity or mortality.