Pediatric papillary thyroid carcinoma: outcomes and survival predictors in 2504 surgical patients.

OBJECTIVE: To evaluate outcomes and predictors of survival of pediatric thyroid carcinoma, specifically papillary thyroid carcinoma.
METHODS: SEER was searched for surgical pediatric cases (≤20 years old) of papillary thyroid carcinoma diagnosed between 1973 and 2011. Demographics, clinical characteristics, and survival outcomes were analyzed using standard statistical methods. All papillary types, including follicular variant, were included.
RESULTS: A total of 2504 cases were identified. Overall incidence was 0.483/100,000 persons per year with a significant annual percent change (APC) in occurrence of 2.07 % from baseline (P < 0.05). Mean age at diagnosis was 16 years and highest incidence was found in white, female patients ages 15-19. Patients with tumor sizes <1 cm more likely received lobectomies/isthmusectomies versus subtotal/total thyroidectomies [OR = 3.03 (2.12, 4.32); P < 0.001]. Patients with tumors ≥1 cm and lymph node-positive statuses [OR = 99.0 (12.5, 783); P < 0.001] more likely underwent subtotal/total thyroidectomy compared to lobectomy/isthmusectomy. Tumors ≥1 cm were more likely lymph node-positive [OR = 39.4 (16.6, 93.7); p < 0.001]. Mortality did not differ between procedures. Mean survival was 38.6 years and higher in those with regional disease. Disease-specific 30-year survival ranged from 99 to 100 %, regardless of tumor size or procedure. Lymph node sampling did not affect survival.
CONCLUSIONS: The incidence of pediatric papillary thyroid cancer is increasing. Females have a higher incidence, but similar survival to males. Tumors ≥1 cm were likely to be lymph node-positive. Although tumors ≥1 cm were more likely to be resected by subtotal/total thyroidectomy, survival was high and did not differ based on procedure.