[Differentiated thyroid gland carcinoma in children and adolescents]

Differentiated thyroid cancer is a rare disease in childhood and adolescence. Most frequently, thyroid cancer in children belongs to the papillary variant, whereas a follicular histological pattern is much less frequently encountered. Dedifferentiated (anaplastic) cancers are very rare at this age. Especially indolent cervical lymph node enlargement is suspicious for a thyroid cancer, even more when occurring together with a solitary, rapidly growing, and indurated thyroid nodule. Every nodule in the thyroid of children and adolescents, if not unequivocally cystic, is suspicious of a malignancy. In contrast to adults, multifocal tumor manifestations are frequently found in children and adolescents which often have spread beyond the capsule of the thyroid at the time of diagnosis. Regional lymph nodes are involved in up to 90%, and distant metastases are present in up to 20% of the cases. Despite these much more advanced stages as usually found in adults, the prognosis of children is better than at advanced age, since these tumors are highly differentiated, and, even in the case of distant metastases, a curative approach is still possible. The therapy (surgery/radioiodine) and the follow-up follows the same principles as those which have been established for older patients.