Prophylactic thyroidectomy in pediatric multiple endocrine neoplasia type 2: A single-institution case series

To characterize perioperative and postoperative outcomes in children with multiple endocrine neoplasia type 2 (MEN2) who underwent prophylactic total thyroidectomy (PT) at a single quaternary-care pediatric institution, with emphasis on postoperative hypocalcemia, hypoparathyroidism, and major surgical complications.

Retrospective single-institution case series.

Quaternary-care children's hospital (Monroe Carell Jr. Children's Hospital at Vanderbilt, Nashville, Tennessee).

Medical records of all patients aged ≤17 years with MEN2 who underwent PT between October 2006 and June 2023 were reviewed. Demographic, genetic, perioperative, and postoperative data were extracted. The primary outcome was postoperative biochemical hypocalcemia (serum calcium< 8.0 mg/dL or ionized calcium< 4.0 mg/dL). Secondary outcomes included permanent hypoparathyroidism, recurrent laryngeal nerve (RLN) injury, and other surgical complications. Exploratory age-stratified analyses were performed to assess whether younger age at surgery was associated with increased complication risk.

Twenty patients were included (median age 6.30 years [IQR 4.38-9.75]; range 2.09-14.16; 10 male [50%]). All patients had MEN2A; the most frequently mutated codon was 620 (n = 9, 45%), including C620R (n = 7) and C620F (n = 2). Eleven patients (55%) developed transient postoperative biochemical hypocalcemia; no patients developed permanent hypo-parathyroidism. Two patients (10%) had medullary thyroid carcinoma (MTC) identified on final pathology, neither of whom had suspected malignancy preoperatively. There were no cases of RLN injury, hematoma, or other major surgical complications. One patient (5%) experienced transient voice changes that resolved completely. In exploratory analyses, age at surgery was not associated with postoperative hypocalcemia (median age 6.55 vs. 6.05 years, hypocalcemia vs. no hypocalcemia; p = 0.82), and patients aged ≤5 years did not have a higher rate of hypocalcemia than older patients (57% vs. 54%; Fisher exact p = 1.0).

PT in pediatric MEN2 can be performed with a low rate of permanent surgical morbidity, including in children aged five years and younger. Transient hypocalcemia occurred in the majority of patients but was universally self-limited, and no patient developed permanent hypoparathyroidism. Occult MTC was identified in 10% of cases, reinforcing the oncologic rationale for prophylactic intervention. These findings support comprehensive preoperative family counseling emphasizing the likelihood of transient electrolyte disturbances while reassuring families regarding the rarity of permanent sequelae.