Abstract: Although with a standardized incidence of 0.54 cases per 100,000 persons, differentiated thyroid cancer (DTC) is a rare disease in children and adolescents, it nonetheless concerns ~1.4% of all pediatric malignancies. Furthermore, its incidence is rising. Due to the rarity and long survival of pediatric DTC patients, in most areas of treatment little evidence exists. Treatment of pediatric DTC is therefore littered with controversies, many questions therefore remain open regarding the optimal management of pediatric papillary thyroid cancer (PTC), and many challenges remain unsolved. In the present review, we aim to provide an overview of these challenging areas of patient and disease management in pediatric PTC patients. Data on diagnosis, surgery, radionuclide, and endocrine therapy are discussed, and the controversies therein are highlighted.


Keywords: pediatric cancer, papillary thyroid cancer, survival, I-131 therapy, follow-up, treatment 


INTRODUCTION

Although with a standardized incidence of 0.54 cases per 100,000 persons,1 differentiated thyroid cancer (DTC) is a rare disease in children and adolescents; it nonetheless concerns ~1.4% of all pediatric malignancies. Furthermore, its incidence is rising.2 In children and adolescents, DTC almost exclusively manifests in the form of papillary thyroid cancer (PTC).

Pediatric PTC shows no relationship with gender in prepubertal children. However, with increasing age, the incidence of PTC also increases, especially in young female adolescents.2,3 In the case of DTC diagnosis, these patients more or less exclusively present with a well-differentiated PTC.

Compared to adults, children more often present with lymph node and/or disseminated (so-called miliary) lung metastases. The latter usually only becomes apparent after radioactive iodine (RAI), as they are usually not visible when morphologic imaging techniques such as X-ray or computed tomography (CT) are used. Fortunately, in these young patients, PTC is almost guaranteed to show an avid uptake of RAI. As a result, prognosis in the pediatric PTC population is excellent when appropriate treatment is administered.