Endocrine Abstracts

Introduction: MEN4 syndrome is a recently described form of MEN in patients with parathyroid and anterior pituitary tumors, which may also develop bronchial, gastric and pancreatic neuroendocrine tumors. In general, the patients present with clinical signs of primary hyperparathyroidism and simptoms caused by pituitary hormones hypersecretion or due to the tumor mass. However, clinical cases with the coexistence of pituitary tumors and pheochromocytoma are very rare described.

Case presentation: We present a young male patient of 44 years old, who presented in our department for endocrinological pre-operative assessment of a pituitary macroadenoma. The brain MRI indicated a macroadenoma (31/30/21 mm) with supra- and para-sellar extension, compressing the optic chiasm, optic tract and the 3^rd cranial nerve on the right side. The patient accused acute right blindness starting 2 weeks ago, denying other simptoms. On clinical examination, the patient was obese (BMI=36 kg/m²) and hypertensive (BP =170/100 mmHg). In addition, personal and family medical history were not significant, excepting personal arterial hypertension debut at 36 years old. Endocrinological evaluations showed normal levels of pituitary, thyroid, mineralocorticoid and glucocorticoid hormones. However, there were detected elevated values of parathyroid hormone (110 pg/ml), plasmatic and urinary normetanephrines (250 pg/ml and 900 ug/24 h) and plasmatic chromogranin A (230 ng/ml). Furthermore, abdominal computed tomography have identified a left adrenal nodule of 1.02/1.14 cm with no other lesions. Thus, in the first instance, the patient underwent laparoscopic left adrenalectomy and afterwards transsphenoidal pituitary surgery, after which he regained visual acuity of the right eye and also it was obtained normalized blood pressure values. Adrenal histopathology confirmed the presence of pheochromocytoma. Blood samples were collected for genetic testing.

Conclusion: We present the case of a young patient with pituitary non-functioning macroadenoma and hyperparathyroidism (MEN4syndrome), also associating left pheochromocytoma.

Keywords: MEN 4 phenotype; pheochromocytoma.