Unusual presentation of multiple endocrine neoplasia type 2A in a patient with the C634R mutation of the RET-protooncogene

Abstract

The aim of this paper is to report an atypical presentation of MEN2A, in a patient carrying the C634R mutation of the RET-protooncogene. A 41-year-old Tunisian woman was admitted to our department with newly diagnosed hyperglycemia. She had a history of bilateral urinary stone recurrence, managed successfully on two occasions. On physical examination a thyroid node of 1cm on the left side was found. Laboratory evaluation and imaging findings confirmed the diagnosis of primary hyperparathyroidism. During cervicotomy, the parathyroid adenoma was resected and the thyroid node was suspected to be a carcinoma. Total thyroidectomy, with appropriate neck nodal resection, was performed. Histological examination confirmed the diagnosis of parathyroid adenoma and revealed a multifocal and bilateral medullary carcinoma. These findings led to the diagnosis of multiple endocrine neoplasia. DNA-analysis demonstrated a germline Cys634Arg mutation in the RET-protooncogene. During the postoperative follow-up, blood pressure as well as the level of urinary methoxylated metabolites increased progressively. Imaging findings were compatible with the diagnosis of bilateral pheochromocytoma. In conclusion, this case report of MEN 2A linked to a 634 RET mutation was peculiar by its revelation mode (1) hyperparathyroidism moreover linked to an adenoma and (2) associated with diabetes, mechanisms of which are probably multifactorial (familial type 2 diabetes, hypercalcemia, catecholamines excess).