Approaches to Thyroid Nodules in Paediatric Cancer Predisposition Syndromes.

Assessment of non-medullary thyroid carcinoma risk in a child with a nodule and a cancer predisposition syndrome (PTEN hamartoma tumour syndrome, DICER1 syndrome, familial adenomatous polyposis).

This review synthesises current paediatric guideline recommendations and recent cohort, pathology and molecular studies on thyroid nodules in children and adolescents with cancer predisposition syndromes, focusing on follicular cell-derived nodules and non-medullary thyroid carcinoma. Evidence quantifying syndrome-stratified malignancy risk remains limited and is largely derived from mixed-age or retrospectively ascertained cohorts subject to surveillance and verification bias. High-resolution ultrasound is central to risk stratification and ultrasound-guided fine-needle aspiration remains the cornerstone of evaluation, yet indeterminate results are frequent in follicular-patterned and encapsulated lesions, notably in PTEN hamartoma tumour syndrome and DICER1 syndrome, with sampling error accentuated in polyclonal multinodular disease. Molecular panels optimised for sporadic adult disease may have reduced rule-out utility in this setting; routine thyroglobulin is not recommended and thyroid autoantibodies should remain adjunctive markers. The authors propose a syndrome-adapted multidisciplinary risk-assessment framework and call for prospective multicentre registries.

Synthesis written by Geno'X. For the full original abstract, please refer to the source publication.

The most useful point of this review is a negative one: molecular panels for indeterminate cytology, calibrated on the sporadic adult nodule, lose their rule-out value in a child with a predisposition syndrome — a reassuring result is not reassuring there. The corollary is that fine-needle aspiration remains the weak link precisely in the encapsulated follicular lesions of PTEN and DICER1, where it is used most. The authors propose a framework rather than thresholds, which is honest given the evidence base, but leaves the decision to operate without a numerical anchor.

Analysis by Dr Thibaut Benquey