Changes in disease stratification after 2 years of follow up in a pediatric cohort with differentiated thyroid cancer (DTC)

ELIAS E,; MATEOS F; VENARA MARCELA; COZZANI H; CHIESA A; PAPENDIECK P; MAGLIO S; BERGADÁ I

Washington DC

Congreso; 10th International Meeting of Pediatric Endocrinology; 2017

Sociedad Latinoamericana de Endocrinologia Pediatrica SLEP

Background: Childhood onset DTC has a more aggressive presentation but no overall increase in mortality compared to adults.Objective: to describe the initial postoperative ATA risk classification of a cohort of pediatric patients with DTC treated uniformly and to evaluate the response to initial therapy at 2 years based on the modified ATA dynamic risk stratification (DRS) for adults.Patients and Methods: retrospective study of 17 patients diagnosed with papillary DTC between 2008 and 2015 treated initially with total thyroidectomy and radioactive thyroid ablation. Median age at diagnosis was 13,8 years (range 5,2-18)and 11/17 were pubertal. Initial pediatric ATA risk was classified in low, intermediate and high risk according to TNM, thyroglobulin (TG) and images. Clinical outcome at 2 years was assessed by DRS into 4 categories: excellent response (non evidence of disease [NED]), indeterminate response, biochemical incomplete response and structural incomplete response according to stimulated TG and imaging findings.Results: postoperative ATA risk classification showed 18 %, 18 % and 64% patients with low, intermediate and high risk. DRS at 2 years revealed 47%, 18%, 6% and 29% of patients with excellent, indeterminate, biochemical incomplete and structural incomplete response respectively. At 2 years all low risk patients remained NED while 33% of the intermediate and 36% of the high risk group achieved NED status. Only 1 pubertal patient of the intermediate risk group presented at 2 years a cervical relapse.Conclusions: Our data confirm the aggressiveness of pediatric DTC at presentation assessed by the pediatric ATA risk classification. At 2 years of follow-up clinical outcome by DRS showed a marked change in the cohort risk composition compared to admission. Although preliminary, our results suggest that DRS is a good and useful response to therapy classification in the surveillance of pediatric DTC patients allowing a moreaccurate treatment decision according to changes in biochemical and structural findings.