McCune Albright Syndrome with a Somatolactotroph Pituitary Adenoma Causing Gigantism: Econography and Literature Review

Abstract

McCune Albright syndrome (MAS) is a rare disease due to a sporadic mutation in Gs protein inducing polyostotic fibrous dysplasia, pigmented skin patches and hyper functioning endocrinopathies. We aimed to report its association with a hot thyroid nodule and gigantism. Case report. A man aged 37, with a history of pigmented skin lesions and lameness was referred for acromegaly. He was giant (height = 1.94 m/ target stature = 1.68 m), and had “cafe au lait” spots. Biological analyses argued for pituitary mixed secretion (random growth hormone = 22 ng/ mL, N<5; prolactin = 27 ng/mL, N<10). Brain CT scan showed a pituitary process of 11x10 mm. Thyroid radioiodine scan revealed a hot nodule. Bone x-ray demonstrated large osteolytic lesions in the right femur and pelvis. He was operated on for endocrine tumours. The thyroid nodule was benign and immunohistochemistry pituitary was positive for GH, prolactin and α subunit. Conclusion. Somatolactotrop adenoma causing gigantism associated with MAS is exceptional. It should be known, diagnosed, and treated early to avoid bone deformations and malignant transformation of osseous