Endocrine Abstracts

Introduction: Multiple endocrine neoplasia type 2A (MEN2A) is a rare autosomal-dominant hereditary cancer syndrome characterized by medullary thyroid carcinoma (MTC), pheochromocytoma, and primary hyperparathyroidism. Pregnancy complicating MEN2A is exceedingly rare, with only 29 reported cases. This case discusses an unusual instance where an enlarged thyroid, displaying sonographic features indicative of cancer, led to the diagnosis and management of RET proto-oncogene-positive MEN type 2A during pregnancy.

Clinical case: A 34-year-old woman, initially seen for hyperglycemia, received a diagnosis of type 1 diabetes mellitus and insulin therapy was initiated. Subsequent thyroid sonography revealed suspicious hypoechoic nodule (~0.8×0.7 cm, EU-TIRADS 4). Fine-needle aspiration confirmed MTC, with markedly elevated calcitonin levels (9.9 pmol/l, normal range <2.6 pmol/l). Parathyroid hormone, serum total calcium, metanephrine, and normetanephrine levels were within normal ranges. The patient underwent genetic testing confirming a positive nucleotide sequence analysis of the RET proto-oncogene, establishing the MEN2A syndrome diagnosis. The confirmation of MTC coincided with the patient’s pregnancy at gestational week 5. Subsequently, a decision was made to perform thyroidectomy immediately after the termination of pregnancy, with the expectation that MTC would manifest in a non-aggressive manner. During the second trimester at gestational week 20, repeated assessments showed a twofold increase in calcitonin levels (23.9 pmol/l) and an enlarged right lobe with a hypoechoic nodule (0.7 × 0.6 cm, EU-TIRADS 5) containing microcalcifications. The left lobe displayed a similar nodule (0.5 × 0.4 cm, EU-TIRADS 5), confirming disease progression. The clinical case was discussed by a multidisciplinary team, resulting in a consensus that determined the necessity of total thyroidectomy with lymphadenectomy during pregnancy. The operation proceeded without complications. After the baby was delivered, a suprarenal glands MRI was arranged, revealing no pathological findings. Calcitonin and metanephrines were in the normal range, and a follow-up checkup for recurrence is scheduled for a year later. The patient was also advised to undergo RET genetic screening for the baby and family members to rule out the same mutation in the RET proto-oncogene. A mutation has been

Conclusion: Managing rare conditions like MEN2A during pregnancy necessitates heightened awareness and comprehensive clinical assessment. Early detection and intervention are crucial, emphasizing the significance of the RET proto-oncogene mutation in MTC. This case underscores the delicate balance required in managing such cases, emphasizing the importance of a multidisciplinary approach.