Endocrine Abstracts

JOINT2370

Introduction: Multi-secretory pituitary adenomas have been reported in the literature. However, tumors with dual corticosomatotropic secretion are very rare. Our observation illustrates This particular entity.

Observation: A 34-year-old patient complaining of decreased libido and right unilateral temporofrontal headaches was referred to us with suspicion of Cushing’s syndrome. Clinically, there were signs of hypercortisolism (cushingoid facies, faciotruncular obesity; abdominal purple stretch marks; filling of the supraclavicular fossae; and skin fragility with bruising on the legs). There were no signs of hypersomatotropism. The hormone profile was consistent with ACTH-dependent Cushing’s syndrome, with a slight hyperprolactinemia of disconnection, corticotropic and thyrotropic insufficiency, and a growth hormone level of 1.5*normal. MRI revealed a left laterosellar lesion measuring 14*22*10.5 mm. After trans-sphenoidal surgery, histological examination combined with IHC revealed a pituitary adenoma with positive immunostaining for GH and ACTH. The evolution over 1 year was marked by tumour recurrence with visual repercussions requiring recourse to surgery.

Discussion: Pituitary adenomas can express and secrete different hormones. The expression of pituitary hormones in non-neoplastic pituitary cells is regulated by various transcription factors. The most important of these are PIT1 and GATA 2. It is well known that some cases of pituitary adenoma producing growth hormone (GH) may be accompanied by hypersecretion of other anterior pituitary hormones such as prolactin (PRL) or thyroid-stimulating hormone (TSH). From an immunohistochemical point of view, other hormone-producing cells of the anterior pituitary can be detected among the GH-producing cells. However, a case of GH-secreting adenoma accompanied by ACTH secretion is extremely rare. the extreme rarity of the combination of GH and ACTH could be attributed to the suppressive effect of hypercorticism on GH secretion. Multiple hormone secretion may result either from neoplastic transformation of 2 cell lines or from differentiation of one cell into a cell secreting another hormone. Surgery is often required as a matter of urgency, somatostatin analogue treatment is indicated in these patients, and monitoring is imperative.

Conclusion: We report a new observation of a rare case of pituitary adenoma co-secreting ACTH and GH responsible for hypercorticism but without notable clinical signs of acromegaly. More meticulous endocrinological and immunohistochemical examination of cases of GH-secreting adenomas could reveal the true incidence of this combination.