Acromegaly, multinodular goiter and silent polyostotic fibrous dysplasia. A variant of the McCune-Albright syndrome

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

BACKGROUND

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.

METHODS

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.

RESULTS

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.

Clinical Characteristics and Management of Patients With McCune-Albright Syndrome With GH Excess and Precocious Puberty: A Case Series and Literature Review

Background

McCune-Albright syndrome is a rare disorder characterized by fibrous dysplasia, café au lait skin spots, and hyperfunctioning endocrinopathies. The coexistence of precocious puberty and growth hormone excess in McCune-Albright syndrome is rare. Both conditions can manifest as accelerated growth, and treatments can be more challenging for such patients. This study aimed to describe the clinical manifestations of combined GH excess and PP in the context of McCune-Albright syndrome and analyze the clinical features and treatments of these patients.

Method

Clinical data from 60 McCune-Albright syndrome patients from Peking Union Medical College Hospital were obtained. The demographic characteristics, growth hormone, insulin-like growth factor-1, prolactin, alkaline phosphatase, and sex hormone levels; growth velocity; and bone age data were obtained. The growth velocity Z-score, bone age over chronological age ratio, and predicted adult height Z-score were calculated before and after treatment. Published studies and case reports were systemically searched, and data on demographic, clinical, and biochemical characteristics and treatment outcomes were obtained.

Results

We reviewed seven patients among 60 McCune-Albright syndrome patients at Peking Union Medical College Hospital (5 female) and 39 patients (25 female) from the published literature. Six of the seven patients from Peking Union Medical College Hospital and half of the patients from the published studies were pediatric patients. These patients had increased growth velocity Z-scores and bone age over chronological age ratios. After good control of both conditions, the growth velocity Z-score and bone age over chronological age ratio decreased significantly, and the predicted adult height Z-score increased. The final heights and predicted adult height Z-scores were not impaired in patients with gigantism. All the patients had craniofacial fibrous dysplasia associated with optic and otologic complications.

Conclusion

McCune-Albright syndrome with growth hormone excess and precocious puberty is more common in girls. Patients have accelerated linear growth and advanced skeletal age, and early and good control of both conditions leads to a reduced growth velocity and stabilized bone age. The predicted adult and final heights are not negatively affected when growth hormone excess is diagnosed in pediatric patients.

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.

Treatment protocols for growth hormone-secreting pituitary adenomas combined with craniofacial fibrous dysplasia: A case report of atypical McCune-Albright syndrome

McCune-Albright syndrome (MAS) is a rare, post-zygotic (non-germline) disorder, characterized by hypersecretory endocrinopathies, fibrous dysplasia of the bone and café-au-lait macules. The most common endocrine dysfunction is gonadal hyperfunction; thus, hypersecretion of growth hormones (GHs) as a manifestation of endocrine hyperfunction in MAS is rarely reported. MAS affects both genders, although the majority of cases have been reported in young females. Atypical presentations of MAS, with only one or two of the classic symptoms, have been previously described, but remain particularly challenging due to the lack of a diagnostic phenotype. In patients with atypical MAS, analysis of mutations in the gene of the α-subunit of the stimulatory G-protein is limited; thus, diagnosis is based on clinical judgment. In the present study, a male with polyostotic fibrous dysplasia and GH-secreting pituitary adenomas, diagnosed with atypical MAS, was reported. The pituitary adenoma was effectively treated with radiotherapy and the patient underwent surgery for the polyostotic fibrous dysplasia, with marked improvements observed in appearance.

Acromegaly and McCune-Albright syndrome

BACKGROUND

McCune-Albright syndrome (MAS) includes the triad of poly/monostotic fibrous dysplasia, café-au-lait spots, and hyperfunctioning endocrinopathies. Acromegaly affects around 20% of MAS patients.

AIMS

The objective was to review all reported cases of acromegaly associated with MAS.

METHODS

All studies and case reports of acromegaly in patients with MAS were systematically sought in the world literature up to January 2013. We also included new data (from three unreported cases) and updated data on 23 previously reported patients from our two centers.

RESULTS

We reviewed the cases of 112 patients (65 males). Mean age at diagnosis of acromegaly was 24.4 years (range, 3-64). Among the 40 pediatric patients, 23 (57%) had precocious puberty. GH/IGF-1 excess was suggested by accelerated growth in 85% of pediatric cases. Acromegaly was almost always associated with skull base fibrous dysplasia. Modern imaging techniques (computed tomography or magnetic resonance imaging) revealed an adenoma in 54% of the patients (macroadenoma in more than two-thirds). Median GH levels and mean IGF-1 SD score at diagnosis were 57 μg/L (2.8 to 291 μg/L) and 8 (2.3 to 24), respectively. Hyperprolactinemia was present in 81% (mean, 149 μg/L; range, 21-600). Pituitary surgery, performed in 25 cases, very rarely cured the GH/IGF-1 excess. Somatostatin analogs improved GH/IGF-1 levels in most patients but achieved control of acromegaly in only 17 (30%) of 56 patients. Pegvisomant achieved normal IGF-1 levels in 10 of 13 cases.

CONCLUSION

Acromegaly, which is present in 20-30% of patients with MAS, raises particular diagnostic and therapeutic issues.

McCune-Albright syndrome: surgical and therapeutic challenges in GH-secreting pituitary adenomas

McCune-Albright syndrome (MAS) is a postzygotic (non-germline) disorder characterized by polyostotic fibrous dysplasia, cafe-au-lait macules and hypersecretory endocrinopathies. A significant percentage of MAS patients have pituitary adenomas that are either growth hormone (GH) or mixed GH/prolactin (PRL)-producing. Surgical excision may be challenging-or even impossible-due to the associated severe fibrous dysplasia of the skull base. Treatment relies on an interdisciplinary, multi-modal approach from endocrinologists, neurosurgeons and radiation oncologists. We present two cases of women with MAS and GH-secreting pituitary adenomas, encountered in our 30-year experience with pituitary diseases. The first patient successfully underwent transsphenoidal surgical resection for a pituitary microadenoma in 1997 (at age 18) and again in 2009 for recurrent disease, with a significant reduction in IGF-1 level. Immunohistochemistry (IHC) and electron microscopy (EM), performed on both specimens, showed a mammosomatotroph adenoma with GH, PRL, alpha subunit (+) IHC, with increased fibrous bodies developing over the 13-year interval. Focal hyperplasia could be discerned. EM in 1997 showed an admixture of mammosomatotrophs, mature lactotrophs and somatotrophs, with a bimodal population identified in 2009. The second MAS patient had long-standing polyostotic fibrous dysplasia, but was only recently diagnosed with GH excess and a pituitary adenoma, at the age of 29 years. Surgical resection was not advised in this patient because of the massive obstructive skull-base fibrous dysplasia. Medical therapy was initiated with somatostatin analogues, although responses in both patients have been suboptimal to date. We review the literature on GH excess in MAS to highlight its surgical and medical challenges.

Polyostotic fibrous dysplasia with gigantism and huge pelvic tumor: a rare case of McCune-Albright syndrome

We report a rare case of polyostotic fibrous dysplasia on endocrine hyperfunction with elevated human growth hormone and normal serum level of prolactin. There were some differential points of gender, gigantism, endocrine function, and GNAS gene from McCune-Albright syndrome. Malignant transformation was suspected in the pelvic tumor from imaging because rapid growth of the tumor by imaging was observed; however, no malignant change occurred in this case.

[Hyperthyroidism related to McCune-Albright syndrome: report of two cases and review of the literature]

INTRODUCTION

McCune-Albright syndrome is a sporadic disease clinicaly characterized by polyostotic fibrous dysplasia, "café-au-lait" cutaneous spots and hyperfunctional endocrinopathies, such as precocious puberty, hyperthyroidism, acromegaly and others. The biologic physiopathology of the disease is based on an activating mutation of the gene for the Gs protein which mediates the activation of adenyl cyclase and subsequent gland autonomous secretion. The thyroid gland is usually involved in this disease, being hyperthyroidism the second most common endocrinopathy seen after precocious puberty.

OBJECTIVE

Revision of the literature since 1937 to 1997, adding our casuistic and discussing the adequate treatment for the hyperthyroidism in the syndrome.

RESULTS

Among 85 cases identified with the syndrome, hyperthyroidism treatment was described in 26 of them. Fifteen were submitted to surgery (total thyroidectomy), 6 were submitted to iodotherapy and 5 were treated with antithyroid drugs (ATD - propylthiouracil, carbimazole or methimazole). In some cases, treatment association was done.

CONCLUSION

McCune-Albright syndrome is a rare disease, combining polyostotic fibrous dysplasia, "café-au-lait" cutaneous spots and hyperfunctional endocrinopathies. Cases with hyperthyroidism are treated initially clinically, but definitive ablation with surgery or radioiodine treatment is the most indicated option.

Transsphenoidal surgery in a patient with acromegaly and McCune-Albright syndrome: application of neuronavigation

The McCune-Albright syndrome (MAS) is characterized by a clinical triad of polyostotic fibrous dysplasia, café-au-lait hyperpigmented macules, and hypersecretory endocrinopathies. Acromegaly is an uncommon manifestation of the endocrine disturbance associated with MAS, and the role of surgery in managing these cases has been a topic of debate. The authors present the case of a 35-year-old man with MAS who was also diagnosed with acromegaly, hyperprolactinemia, and pituitary macroadenoma. The patient had an 18-year history of fibrous dysplasia involving the right frontal bone and ribs as well as multiple endocrinopathies, but no cutaneous hyperpigmented macules. An oral glucose tolerance test demonstrated partial suppression of plasma levels of growth hormone (GH). The patient underwent transsphenoidal resection of the pituitary tumor, performed with assistance of neuronavigation, and tolerated the procedure well. After the surgery, both prolactin and GH levels returned to normal. These results suggest that neuronavigation-assisted transsphenoidal surgery can safely remove pituitary adenomas associated with MAS and successfully treat the underlying endocrine abnormalities.

Acromegaly with fibrous dysplasia: McCune-Albright Syndrome -- clinical studies in 3 cases and brief review of literature--

The McCune-Albright syndrome (MAS) is characterized by a triad of poly/monostotic fibrous dysplasia, café-au-lait macules and hyperfunctioning endocrinopathies including growth hormone (GH) excess. Polyostotic bone lesions and café-au-lait macules are common while monostotic bone lesions are rare. Similarly, acromegaly as a manifestation of endocrine hyperfunction with MAS is uncommon and in most of the instances somatotropinoma has not been documented. We report 3 patients, two of them had monostotic lesion, none had café-au-lait macules and all had GH secreting pituitary macroadenoma. All of them underwent transfrontal pituitary adenomectomy and had histopathological confirmation of GH secreting pituitary adenoma. A brief review of literature is also presented.

Clinical, endocrinological and radiography features in a child with McCune-Albright syndrome and pituitary adenoma

McCune-Albright syndrome is a rare syndrome presenting with polyostotic dysplasia, cafe-au-lait spots and multiple endocrinopathies that is very often combined with precocious puberty. We examined the clinical, endocrinological and radiological features in a boy with McCune-Albright syndrome and pituitary adenoma. X-rays, magnetic resonance (MRI) scan, whole body scintigraphy, single photon emission computer tomography (SPECT) and 3D-reconstruction from bone SPECT was performed to evaluate clinical improvement after treatment with sandostatin and pamidronic acid. After a six-month period of treatment with sandostatin and pamidronate, bone scintigraphy revealed significantly reduced activity. Treatment with bromocriptine and methimazole led to normalization of prolactin and thyroid hormone levels. Mobility of the patient improved. A significant improvement as a result of treatment with sandostatin and pamidronic acid was found in this patient with generalized fibrous dysplasia. So far, this condition has been treated with pamidronate only in adults, but severely affected children also benefit from this treatment regimen.

A case of pituitary adenoma associated with McCune-Albright syndrome

A 11-year-old boy presented with right temporal hemianopsia and was evaluated of a possible pituitary adenoma. At the age of six, he underwent surgery for facial deformities due to fibrous dysplasia. On admission, he had acromegalic features, was 170 cm tall, weighing 66 kg. The left side of his face was slightly deformed, and a café-au-lait spot was found on his right face. Endocrinologic examination revealed elevated basal level of serum GH (103.6 ng/ml, normal < 3 ng/ml) and PRL (259.1 ng/ml, normal < 30 ng/ml). Other endocrine functions were normal. CT showed hyperostosis of the right frontal, occipital, sphenoidal and maxillary bones. Magnetic resonance imaging (MRI) revealed a pituitary macroadenoma with intraadenomatous cyst. On the basis of physical, endocrinologic and neuroradiologic examination, our diagnosis was pituitary adenoma with McCune-Albright syndrome. Surgery was performed by subfrontal approach. By light microscopy, the pituitary tumor represented a typical acidophilic adenoma. Immunoreactivity for GH and PRL were evident in most of the adenoma cells. Double immunostaining for GH and PRL demonstrated the co-existence of the two hormones in a few adenoma cells. However the majority of cells expressed only one hormone. After surgery the right temporal hemianopsia improved. Postsurgical endocrinologic examination revealed reduction in basal serum GH and PRL levels. Administration of bromocriptine decreased blood PRL levels but it had a limited action on GH hypersecretion.

Hyperthyroidism in McCune-Albright syndrome with a review of thyroid abnormalities sixty years after the first report

We present a patient with hyperthyroidism associated with McCune-Albright syndrome (MAS). MAS is a sporadic genetic disease characterized by polyostotic fibrous dysplasia, cafe au lait cutaneous spots and endocrinopathies (peripheral precocious puberty, thyroidopathies, acromegaly, etc.). It is caused by an activating mutation of the gene for the Gs alpha membrane-associated protein, which mediates the thyrotropin (TSH)-induced and other hormone-induced activation of adenylyl cyclase. A 13-month-old girl was diagnosed with MAS. Precocious puberty was treated initially with testolactone and later with oophorectomy. Subclinical hyperthyroidism was detected biochemically at birth, and 10 months later, it became clinically evident, albeit mild, with absence of goiter. A concomitant liver dysfunction precluded treatment with thionamides and she was sporadically treated with beta-blockers. The combination of increased free thyroxine (T4) and triiodothyronine (T3) with low plasma thyrotropin (TSH) levels in the absence of thyroid-stimulating autoantibodies persisted until the age of 6 years, when she was referred to our unit. Hyperthyroidism was then clinically evident with cardiac hyperactivity, and it was cured with administration of radioiodine (131I). Thyroid disease is the second most common endocrinopathy associated with MAS, and since 1936, 63 cases of thyroidopathies have been described, including 19 nodular (14 with and 5 without hyperthyroidism) and 23 diffuse (20 with and 3 without hyperthyroidism) goiters, and 18 cases of hyperthyroidism without goiter. The previously described somatic activating mutation of the gs alpha gene in the ovaries, the liver and the peripheral blood of our patient, in the absence of stigmata, autoimmunity might be incriminated for the secretory and mitotic activation of the thyroid gland. We suggest the treatment of choice of hyperthyroidism in MAS patients should be 131I administration because: (a) hyperthyroidism is very likely to recur after withdrawal of antithyroid medication; (b) the morbidity of these patients is elevated; (c) oophorectomized patients do not need to be advised to avoid procreation during the months after 131I administration; and (d) finally, even in the usual cases of hyperthyroidism in childhood, 131I treatment is becoming more popular worldwide.

Clinical implications of genetic defects in G proteins. The molecular basis of McCune-Albright syndrome and Albright hereditary osteodystrophy

Inactivating and activating mutations in the gene encoding G alpha s (GNAS1) are known to be the basis for 2 well-described contrasting clinical disorders, Albright hereditary osteodystrophy (AHO) and McCune-Albright syndrome (MAS). AHO is an autosomal dominant disorder due to germline mutations in GNAS1 that decrease expression or function of G alpha s protein. Loss of G alpha s function leads to tissue resistance to multiple hormones whose receptors couple to G alpha s. By contrast, MAS results from postzygotic somatic mutations in GNAS1 that lead to enhanced function of G alpha s protein. Acquisition of the activating mutation early in life leads to a more generalized distribution of the mosaicism and is associated with the classic clinical triad of polyostotic fibrous dysplasia, endocrine hyperfunction, and café au lait skin lesions described in MAS. Acquisition of a similar activating mutation in GNAS1 later in life presumably accounts for the restricted distribution of the gsp oncogene, and is associated with the development of isolated lesions (for example, fibrous dysplasia, pituitary or thyroid tumors) without other manifestations of MAS. Tissues that are affected by loss of G alpha s function in AHO are also affected by gain of G alpha s function in MAS, thus identifying specific tissues in which the second messenger cAMP plays a dominant role in cell growth, proliferation, or function. Further investigations of the functions of G alpha s and other members of the GTPase binding protein family will provide more insight into the pathogenesis and clinical manifestations of human disease.

McCune-Albright syndrome

McCune-Albright syndrome (MAS) is characterized by the clinical triad of polyostotic fibrous dysplasia, cafe-au-lait pigmented skin lesions, and multiple endocrinopathies. The molecular basis of MAS is a mutation in G(s)alpha that results in constitutive activation of adenylyl cyclase in affected tissues. This mutation occurs during early embryogenesis, and therefore patients with MAS are mosaic. The identification of activating mutations of Gsa in liver, heart, and gastrointestinal tract of patients with MAS suggests a broader spectrum of clinical disease than previously appreciated.

Presurgical octreotide treatment in acromegaly

The aim of this study was to determine the role of octreotide administration in acromegalic patients as a preparation for selective adenomectomy using transsphenoidal route. Octreotide was administered for 3 to 6 weeks before surgery in 12 patients and for 4 to 39 months in 25 patients. The clinical response was judged as excellent or good in 10 of 12 patients from group I and in 23 of 25 patients from group II. Marked reduction (ie, greater than 50% of initial values) in serum growth hormone (GH) levels was seen in all patients, with levels to less than 5 micrograms/L in 68% of patients and less than 2 micrograms/L in 27%. Insulin-like growth factor 1 (IGF-1) levels decreased to within normal limits in half the cases. During long-term treatment, an escape phenomenon could be seen. Varying degrees of tumor shrinkage were seen in more than 50% of cases. During surgery, with regard to the relative ease or difficulty in removing the tumor, the consistency of the tumor and the separation of normal from pathological tissue, no significant difference was observed between patients given octreotide and those from control series. Morphological changes in adenomatous tissue were rather small. The surgical outcome was similar in the pretreated series as in the control series, except in enclosed adenomas, which showed a tendency to a higher success rate. Since octreotide improves both the clinical condition and hormonal parameters and induces varying degrees of tumor shrinkage, it is potentially useful as an adjunct to surgery. Morphological data suggest that octreotide exercises a functional inhibitory effect on GH release.

Octreotide therapy of growth hormone excess in the McCune-Albright syndrome

We report a patient with the McCune-Albright syndrome and growth hormone excess. Biochemical evaluation demonstrated characteristic changes typical of acromegaly, and an unusual pattern of delayed somatotropin response to hGHRH40, not previously described in this syndrome. Therapeutic trial of low-dose octreotide successfully reversed his growth hormone excess, whereas bromocriptine failed to reduce growth hormone levels. Previous reports of acromegaly and McCune-Albright syndrome are reviewed, and the unique features of this case discussed.