Clinical characteristics and management of growth hormone excess in patients with McCune-Albright syndrome.

OBJECTIVE: McCune-Albright syndrome (MAS) is a sporadic, postzygotic disease presenting with fibrous dysplasia, cafe-au-lait spots and multiple endocrinopathies. Growth hormone (GH) excess is an uncommon but potentially severe complication of MAS. This study aims to describe the clinical manifestations of GH excess in the context of MAS and analyze the responses of these patients to treatments.

DESIGN: Retrospective clinical study.

METHODS: Clinical data from 52 MAS patients were analyzed. Serum GH and IGF1 levels, as well as nadir GH levels after an oral glucose tolerance test and alkaline phosphatase (ALP) levels were determined before and after the treatment.

RESULTS: In total, 13 MAS patients (25%) had the complication of GH excess, including 10 males (76.9%). Among them, all had FD, and 6 patients had sphenoidal bone involvement. Visual deficits were present in 8 patients, and hearing deficits were present in 5. Olfactory dysfunction was observed in 3 patients. Evident pituitary adenomas were confirmed in 9 patients by MRI. These patients underwent surgery with or without pretreatment of long-acting somatostatin analogue octreotide, and 6 achieved complete remission. The serum ALP levels decreased significantly after treatment for GH excess.

CONCLUSIONS: MAS with GH excess is more common in male patients. GH excess can lead to more severe skeletal lesions in MAS patients involving more of the craniofacial bones. Complete trans-sphenoidal complete tumor excision with neuronavigational guidance is effective and could lower ALP levels. LAR is recommended as a preoperative treatment and when patients fail to achieve complete remission after surgery.