Pituitary adenoma-neuronal choristoma is a pituitary adenoma with ganglionic differentiation

Sellar Gangliocytoma: Case Report and Review of an Extremely Rare Tumour

Sellar gangliocytomas (SGs) are rare, well-differentiated, low-grade neoplasias that commonly present along with a pituitary adenoma (PA). We describe a case of a 52-year-old woman with a 2-year history of headache, body weight increase, and recent onset of arterial hypertension and type 2 diabetes mellitus. Work-up tests revealed a normal hypophyseal profile, except for mild ACTH elevation, and a sellar mass on magnetic resonance imaging (MRI). A diagnosis of an enlarging pituitary macroadenoma was established, and to prevent symptom progression, the tumour was resected. Pathology showed 2 cell populations: ganglion and corticotrope cells. Three years after surgery, the patient no longer had a headache but persisted with arterial hypertension and type 2 diabetes mellitus. A literature review produced 207 cases of SGs. They typically present in women at 40 years of age and the most common clinical presentation are symptoms of acromegaly. Of the documented cases, 74 and 93% were treated with surgery alone or combined treatments (radiotherapy, radiosurgery, or pharmacotherapy), respectively. The majority of deaths associated with a SG came from the first half of the 20th century. In conclusion, this patient presented with a silent SG with likely pituitary hyperplasia. SGs are a challenging diagnosis, have a benign course, and may provide insights into PA tumourigenesis.

Unilateral hydrocephalus from a gangliocytoma-somatotrophinoma: first reported case

SUMMARY

Although pituitary macroadenomas often cause mass effects on surrounding structures, it is extremely rare for pituitary lesions to disturb cerebrospinal fluid circulation. Sellar gangliocytoma-pituitary adenomas (SGPAs) are also extremely rare. Here we report the unique case of a man with the unusual combination of acromegaly from an SGPA, who presented with unilateral hydrocephalus. A 60-year-old man presented with rapid neurological deterioration, bitemporal hemianopia, and acromegalic features. Neuroimaging revealed a large sellar lesion extending superiorly into the left foramen of Monro, causing acute obstructive unilateral hydrocephalus. External ventricular drain placement improved consciousness immediately. Biochemical assessment confirmed acromegaly. Following trans-sphenoidal debulking, histology revealed a mixed gangliocytoma/sparsely-granulated somatotrophinoma. Despite the residual disease, his vision recovered remarkably, low-dose cabergoline controlled residual excess growth hormone (GH) secretion, and the residual tumour has remained extremely stable over 2 years. Hydrocephalus is an extremely rare complication of pituitary lesions, and unilateral hydrocephalus has never been reported previously. GH secretion in SGPAs is more common than for pituitary adenomas in general, raising questions regarding the aetiology and therapeutic approach to this rare combination tumour.

LEARNING POINTS

Pituitary tumours most commonly present with symptoms related to endocrine disturbance or mass effects upon visual pathways (e.g. optic chiasm, nerves in the lateral cavernous sinus). However, extremely rarely, pituitary masses may disrupt cerebrospinal fluid (CSF) circulation resulting in hydrocephalus. Sellar gangliocytomas are very rare tumours and most of them are hybrid tumours with pituitary adenomas (SGPAs). SGPAs are typically indolent and may be functioning or non-functioning tumours. Growth hormone (GH)-producing SGPAs are less likely to respond to somatostatin agonists than classic somatotrophinomas. Primary surgical debulking via a trans-sphenoidal approach was effective in this individual, leading to the restoration of CSF circulation and improvement in visual disturbance, while also negating the need for permanent CSF diversion despite the residual tumour burden.

Pituitary Gangliocytoma Producing TSH and TRH: A Review of "Gangliocytomas of the Sellar Region"

PURPOSE

Pituitary gangliocytomas (GCs) are rare neuronal tumors that present with endocrinological disorders, such as acromegaly, amenorrhea-galactorrhea syndrome, and Cushing's disease. Most pituitary GCs coexist with pituitary adenomas pathologically and are diagnosed as mixed gangliocytoma-adenomas. Herein, we report a case of 45-year-old man who presented with the syndrome of inappropriate secretion of thyroid-stimulating hormone (SITSH) and discuss the pathogenesis of pituitary GCs.

METHODS

Pituitary magnetic resonance imaging showed an 8-mm homogeneous and poorly enhanced mass inside the pituitary gland. Endoscopic transsphenoidal surgery was performed under a preoperative diagnosis of thyrotroph adenoma. However, the tumor was finally diagnosed as gangliocytoma without an adenomatous component. The tumor was further analyzed via immunohistochemistry and electron microscopy. Additionally, we searched MEDLINE and PubMed for previously published cases of isolated pituitary GCs and analyzed the reported clinicopathological findings.

RESULTS

The patient showed complete clinical and endocrinological recovery after an operation. The tumor was positive for thyrotropin (TSH), TSH-releasing hormone (TRH), Pit-1, GATA-2, and most neuronal markers. Electron microscopy demonstrated the presence of intracytoplasmic secretory granules and neuronal processes. Co-secreting hypothalamic and pituitary hormone inside the tumor indicated autocrine/paracrine endocrinological stimulation.

CONCLUSION

Herein, we report a case of SITSH caused by an isolated pituitary gangliocytoma, expressing both TSH and TRH, which, to our best knowledge, is the first reported case of such a condition. The multidirectional differentiation and multihormonal endocrine characteristics of these tumors indicate that they are a member of neuroendocrine neoplasms, further supporting that they are derived from neural crest cells.

Gangliocytoma: outcome of a rare silent pituitary tumour

The most common finding in front of a pituitary incidentaloma is a silent pituitary adenoma. We describe a 59 years old woman with a pituitary gangliocytoma and her follow-up after 1 year. Hormonal exploration only evidenced partial corticotropic insufficiency. A trans-sphenoidal surgery was performed due to the tumour's suprasellar expansion. Gangliocytoma is a benign tumour of unknown prevalence, belonging to central nervous system tumour with neuronal differentiation, and 129 cases have been reported in the literature. growth hormone (GH), adrenocorticotropic hormone (ACTH) or prolactin secretions have been reported, as these ganglion cell-like mature neurons are usually mixed with secreting pituitary endocrine cells. We report a case with a pure gangliocytoma devoid of symptomatic endocrine secretion, not surrounded by pituitary endocrine tumour cells. Immunochemistry of the tumour was positive for hypothalamic growth hormone releasing hormone (GHRH) and pituitary hormones, such as GH and ACTH. Hence, this immunoexpression was not associated with peripheral hormonal secretions, suggesting biologically inactive hypothalamopituitary hormones.

Characteristics of ganglion cells in pituitary gangliocytomas

The occurrence of ganglion cells in the sella turcica, in association or not with a pituitary adenoma, has been rarely reported. Various names have been employed for this rare entity, gangliocytoma being frequently used and recommended by WHO classification. Expression of cytokeratin in these ganglion cells has been previously occasionally reported, a very intriguing observation raising questions on the possible nature and derivation of these cells. We describe the pathological findings in three cases of growth hormone-producing adenomas, all sparsely granulated, showing the presence of a ganglion cell population admixed with an adenomatous component. A review of the literature is also provided.