Original Article Familial Thyroid Cancer

Familial thyroid cancer can arise from follicular cells (familial nonmedullary thyroid cancer, FNMTC) or from parafollicular cells (multiple endocrine neoplasia type II, MEN2). Familial nonmedullary thyroid cancer occurs either as a discrete entity defined by the presence of thy- roid cancers of follicular cell origin within two or more first-degree relatives or as part of other multitumor syndromes. FNMTC is associated with multifocality, aggressive behavior and fre- quent recurrences, and therefore should be treated aggressively. Family members are at an in- creased risk of developing thyroid cancer and need to be followed closely. For patients with medullary cancer, genetic testing for a RET mutation is necessary for timely detection of other MEN2 manifestations particularly pheochromocytomas and early identification of new family members who are gene carriers. Patients with MEN2B should undergo total thyroidectomy during infancy and prophylactic thyroidectomy should be performed in other gene carriers be- fore 5 to 10 years of age. Clinicians must be aware of psychosocial and ethical issues related to patients with familial thyroid cancer and their family members.