Influence of body mass index at diagnosis on outcome of thyroid cancer in children and adolescents.

Abstract Purpose To systemically examine the relationship between body mass index, the extent of thyroid cancer and metastatic burden at diagnosis, and overall outcomes in children and adolescents with thyroid cancer. Methods A retrospective series of children and adolescents with differentiated thyroid cancer who underwent total thyroidectomy and 131I therapy was analyzed. Body mass index (BMI) at the time of surgery was assessed. The Chinese age- and sex-specific BMI percentile criteria for screening overweight and obesity in children and adolescents were used to define the overweight and obesity among patients. The relationship between BMI and clinicopathological features and clinical outcomes of the disease was evaluated by logistic regression modeling, incorporating the eighth edition of the American Joint Committee on Cancer TNM staging system and the 2015 American Thyroid Association guidelines. Results This study included 181 children and adolescents with differentiated thyroid cancer (82.9% females, median age 17 years). The mean BMI was 21.0 ± 3.9 kg/m2; 77.9% of the patients (N = 141) were normal weight, 13.2% (N = 24) were overweight, and 8.8% (N = 16) were obese. No positive associations were noted between BMI and T, N, or M stage on logistic regression analyses. The absence of an association was also demonstrated on analysis by BMI categories. After a median follow-up of 51 months, 114 children and adolescents (63.0%) had achieved excellent response to therapy. No associations were noted for persistent/recurrent disease among BMI groups. Conclusion Our study highlights the absence of increased disease burden at the time of thyroid cancer diagnosis in pediatric patients with high BMI along with the same prognosis compared with normal-weight pediatric patients.