McCune-Albright syndrome associated with pituitary adenoma: a clinicopathological study of ten cases and literature review

McCune-Albright syndrome (MAS) is a rare genetic, non-inheritable disease and is characterized by fibrous dysplasia, hyperendocrinism, and café-au-lait macules. Pituitary adenomas could be concurrent with this syndrome but clinicopathological features and the surgical management of such disorders is unclear.

Hormone excess (including GH and PRL) could be significantly reduced and the visual deficits are greatly improved after the surgery without the decompression of the optic canal. In addition, MAS-associated pituitary adenomas have a moderate expression of Ki-67 and positive expression of Gsα and PKA C-beta, indicating a mildly proliferative nature of these tumors and the possible linking between MAS and adenomas.

We retrospectively reviewed ten MAS-associated pituitary adenoma patients with follow-up in Beijing Tiantan Hospital and analyzed their clinicohistological data, surgical strategies, neuro-imaging, genetic mutations, and prognosis. Moreover, a critical review of the English language literature was also conducted.

All of the ten MAS-associated adenoma patients underwent surgeries to remove the tumor (nine transsphenoidal approaches and one transcranial approach). None of these patients had a decompression of the optic canal. Notably, the growth hormone (GH), prolactin (PRL), and IGF-1 level had a significant reduction after the resection of the tumor while vision improvement was observed in most patients (6/7) with visual deficits. No tumor recurrence was observed during the follow-up from 16 to 150 months. The pathological examination showed a moderate Ki-67 LI (mean 1.19%, range from 0.1% to 3.3%) and the positive staining of Gsα and PKA C-beta. GNAS gene mutation (R201C) was detected in one patient. Conclusions: Hormone excess (including GH and PRL) could be significantly reduced and the visual deficits are greatly improved after the surgery without the decompression of the optic canal. In addition, MAS-associated pituitary adenomas have a moderate expression of Ki-67 and positive expression of Gsα and PKA C-beta, indicating a mildly proliferative nature of these tumors and the possible linking between MAS and adenomas.