Endocrine Abstracts

Introduction: Multiple endocrine neoplasia (MEN1) is a rare underdiagnosed inherited multi-tumor syndrome, affecting neuroendocrine and non-endocrine tissues. Its aspects are extremely variable with no genotype-phenotype correlation.

Case report: A 57 year old woman with a history of hypertension, presented five months before her admission with asthenia, headache and vomiting, initial biological exams revealed a central hypothyroidism. A pituitary MRI showed a sellar and suprasellar mass (3 cm of diameter) with an upper deviation of the pituitary stalk, the optic chiasma, and apparent invasion into the left cavernous sinus (knosp 2 at right; knosp1 at left) consistent with a pituitary macroadenoma. Laboratory evaluations concluded to a non-functioning pituitary adenomas with disconnection hyperprolactinemia and hypopituitarism. Ophthalmological examination revealed bitemporal hemianopsia. The patient’s serum investigations revealed a primary hyperparathyroidism. Both parathyroid ultrasound and Technetium Tc-99 m sestamibi parathyroid scintigraphy were negative. The patient did not present any clinical, biological, imaging manifestations of gastro-entero-pancreatic neuroendocrine tumors. The diagnosis of MEN 1 was made and few days after, the patient had a transphenoidal adenomectomy. The surgery was complicated with a transient insipidius diabetes. 3 months after surgery, the evaluation revealed the persistence of hypopituitarism (corticotropic insufficiency, and central hypothyroidism) but a normal prolactin serum level. Pituitary MRI showed a tumor remnant. Visual field was normal.

Discussion: MEN 1, a rare endocrine syndrome, is defined by the presence of 2 or more primary endocrine tumors mainly located at parathyroid glands, anterior pituitary and gastro-enteropancreatic (GEP). Mutations of the MEN1 gene are identified as responsible for the development of this syndrome. Primary hyperparathyroidism, the most common manifestation of MEN1, presents usually in the second to the fourth decade of life. Multiple glandular disease is typical of MEN1. The most common type of pituitary adenoma in MEN1 is a prolactinoma. Conversly, non functioning adenoma are rare (5%). GEP, which are asymptomatic in 70% of cases, are the primary life-threatening manifestation of MEN1 due to their malignant potential.

Conclusion: The peculiarty of our case stems from the fact that MEN1 was revealed at an advanced age by a nonfunctionnig macroadenoma. That’s why it should not be overlooked in diagnosis. In addition early recognition, multidisciplinary management and life long follow up are crucial.