ESPE Abstracts

Background: 2015 ATA Guidelines for management of medullary thyroid cancer (MTC) include C634 RET codon mutation in ‘High risk’ group, recomendating prophylactic thryroidectomy before 5 years old based on serum basal calcitonin levels (SBCt).

Objective and hypotheses: We present 14 pediatric patients with C634 RET codon mutation, who underwent prophylactic thyroidectomy in our center, their clinical and analytical features and anatomopathological findings.

Method: Preoperative SBCt, thyroid function, parathyroid hormone, urinary cathecolamines, cervical ultrasound were performed, besides physical examination. Surgery was performed at diagnosis, except in youngest patients in whom surgeons preferred to wait until 3–4 years old.

Results: Mean age of patients at diagnosis was 8.1 years (18 months–16.5 years). Clinical examination showed palpable thyroid nodule in only one of the patients. SBCt was elevated in 7/14 patients. It was moderately elevated in the oldest patients, and extremely elevated (2400 ng/l; NV: <10 ng/l) in patient presenting goiter. Total thyroidectomy was performed to the whole cohort. Only one patient suffered postsurgery complication, a surgical site hemorrhage solved with a Penrose drainage for 24 h. No other postsurgical complications occurred.

Histopathologic findings were: 10 C cell hyperplasia (CCH), 3 MTC, 1 normal thyroid. Every MTC patient had elevated SBCt, the same as three patients having CCH. The rest of CCH patients presented normal SBCt, even those having atypias.

Conclusion: SBCt cannot reliable discriminate between CCH and MTC. Our recommendation is to perform prophylactic thyroidectomy as soon as high-volume surgeons accept.