08/10/2026
A new report describes a calcitonin-negative medullary thyroid carcinoma (MTC)-like thyroid tumour that was subsequently reclassified as primary thyroid paraganglioma (TPGL) following review by a specialist endocrine pathologist. A three-generation family history subsequently identified carotid body paragangliomas in the father and brother of the patient, with germline testing identifying a heterozygous intronic SDHD variant (NM_003002.4:c.314+4A>G) in all three affected relatives. Peripheral blood RNA sequencing demonstrated activation of a cryptic donor site 4 bp downstream of exon 3, supporting a splice-disrupting effect.
This case report illustrates two practical safeguards in the evaluation of an unusual thyroid tumour: obtaining a comprehensive family history early in the diagnostic process and timely review by a pathologist experienced in endocrine and neuroendocrine tumours.
Read the case report: https://doi.org/10.1530/ETJ-26-0226