{Reference Type}: Case Reports
{Title}: Incidental detection of multiple endocrine neoplasia and medullary thyroid carcinoma before starting GLP-1 agonist: A case report.
{Author}: Glasgow K;Jiminez V;Garcia N;Gillis A;
{Journal}: Heliyon
{Volume}: 10
{Issue}: 12
{Year}: 2024 Jun 30
{Factor}: 3.776
{DOI}: 10.1016/j.heliyon.2024.e33420
{Abstract}: A man, in his 30s, with a history of obesity and hypothyroidism planned to begin taking a new Glucagon-like peptide-1 (GLP-1) agonist for weight loss. As these medications have been associated with C-cell hyperplasia, a calcitonin level was checked as evaluation prior to starting the drug. This returned at 131 pg/mL (upper limit of normal<10 pg/mL), and a subsequent carcinoembryonic antigen was 5.2 ng/mL (ref<3 ng/mL). Thyroid ultrasound was performed and demonstrated bilateral subcentimeter nodules. After total thyroidectomy, final pathology demonstrated bilateral 0.8 cm medullary thyroid carcinoma. Genetic testing revealed a NM_020975.6: c.1826G > A; p.Cys609Tyr. germline RET mutation, confirming the diagnosis of multiple endocrine neoplasia 2 syndrome. The patient recovered well from treatment. His first-degree relatives also underwent genetic testing. This case represents a surprising diagnosis of familial multiple endocrine neoplasia 2A prior to starting a Glucagon-like peptide-1 agonist.