Introduction: Somatotropic adenomas are clinically expressed either by acromegaly or by gigantism according to age of onset. Several histological types are involved. Immunohistochemistry provides conclusive evidence that significant diversity exists between growth hormone secreting (GH) tumors in excess. We report three observations of a particular histological type: mammosomatotropic adenoma.
Observation 1: Mrs. M.H., aged 56, hypertensive for 10 years, followed for acromegaly with a pituitary macro-adenoma for 4 years, operated 3 times. The interrogation found a dysmorphic acromegaloid syndrome evolving for 11 years. The patient was put on cabergoline for 3 years. The hypothalamic-pituitary MRI of control is in favor of a sellar arachnoidocele without visible adenoma, the anatomopathological study speaks of aspect in favor of a mixed pituitary adenoma and immunohistochemistry, an aspect in favor of an adenoma mammosomatotrope.
Observation 2: Mrs. L.F., aged 45 years, hypertensive for 1 year, who presents for a dysmorphic acromegaloid syndrome noted for 5 months. The MRI showed a pituitary macro-adenoma, a surgical procedure was performed and the patient was put on cabergoline. The anatomopathological and immunohistochemical studies have objectified an aspect in favor of a mammosomatotropic adenoma.
Observation 3: Mrs. L.B, aged 43, presenting for an acromegaloid dysmorphic syndrome observed for 7 years. The MRI showed a pituitary macro-adenoma, a surgical procedure was performed and the patient was put on cabergoline. The anatomopathological and immunohistochemical studies have objectified an aspect in favor of a mammosomatotropic adenoma.
Discussion: Mammosomatotropic adenoma is characterized by intense immunohistochemistry antiGH and immunopositivity antiprolactin less, but within the same cell. Electron microscopy confirms this granular colocalization of the two hormones. The diagnosis of multi-hormonal somatotropic adenomas requires the routine practice of immunohistochemical tests because there is no specific clinical presentation.
18 - 21 May 2019
European Society of Endocrinology