Management of Hypoparathyroidism After Total Thyroidectomy for Differentiated Thyroid Cancer in Children and Young Adolescents: Experiences From a Multicenter Cohort in China.

[BACKGROUND] Hypoparathyroidism is one of the most common postoperative complications of total thyroidectomy (TT) in children and young adolescents differentiated thyroid cancer (CAYA-DTC). Due to lack of data in Chinese population, we aimed to investigate their incidence of transient/permanent hypoparathyroidism and relevant clinical risk factors.

[METHODS] A multicenter retrospective cohort of CAYA-DTC patients who underwent TT was launched in three tertiary hospitals in China. Serum PTH and calcium level were measured on the first day after surgery (post-operation Day 1, POD1) and around 6 months during follow-ups. The occurrence of transient hypoparathyroidism was treated as a competing risk factor to the end-point of permanent hypoparathyroidism.

[RESULTS] Among all 104 enrolled patients, the average age was 15.26 ± 2.52 years old. Symptoms of post-operation hypocalcemia were seen in one third. The incidence rate of transient and permanent hypoparathyroidism was 24.0 % and 6.7 %, respectively. Patients with large tumor size, lateral lymph node metastasis (LNM), bilateral involvement or radioactive iodine (RAI) treatment were more likely to develop hypoparathyroidism after surgery (p < 0.05), while only low POD1 PTH level <8 pg/mL and RAI treatment were independence risk factors for permanent hypoparathyroidism (p < 0.01). Puberty (age <14 years old) displayed no significant impact on the incidence of hypoparathyroidism.

[CONCLUSIONS] This is the first report on hypoparathyroidism after TT among Chinese CAYA-DTC. Patients who had low POD1 PTH or underwent postoperative RAI treatment were more likely to develop permanent hypoparathyroidism. Our study provides clinical references for updating post-operation management guidelines in CAYA-DTC in China.