Growth hormone secreting pituitary microadenomas and empty sella - An under-recognized association?

Empty sella in somatotropic pituitary adenomas; a series of 23 cases

Purpose

We aimed to investigate empty sella syndrome in somatotrophic pituitary adenoma for possible etiology, complications, and treatment options.

Method

Among over 2,000 skull base masses that have been managed in our center since 2013, we searched for growth hormone-producing adenomas. Clinical, surgical, and imaging data were retrospectively collected from hospital records to check for sella that lacked pituitary tissue on routine imaging.

Result

In 220 somatotrophic adenomas, 23 patients had an empty sella with surgical and follow-up data. The mean age of the sample was 46 years with the same male-to-female ratio. Five cases had partial empty sella and the rest were complete empty sellas. The most common simultaneous hormonal disturbance was high prolactin levels. Six had adenoma invasion into the clivus or sphenoid sinus and 10 had cavernous sinus intrusion. Peri-operative low-flow and high-flow cerebrospinal fluid (CSF) leaks were encountered in one and two patients, respectively, which were successfully sealed by abdominal fat. The majority of cases required growth hormone replacement therapy while it was controlled without any replacement therapy in nine patients. No pituitary hormonal disturbance occurred after transsphenoidal surgery except for hypothyroidism in one patient.

Conclusion

An empty sella filled with fluid can be detected frequently in pituitary adenomas, especially in the setting of acromegaly. The pituitary gland may be pushed to the roof of the sella and might be visible as a narrow rim on imaging or may be detected in unusual places out of the sella. The pathophysiology behind such finding originates from soft and hard tissue changes and CSF pressure alternations during abundant growth hormone production.

The coexistence of newly diagnosed acromegaly with primary empty sella: More frequent than expected?

OBJECTIVE

We investigated the coexistence of newly diagnosed acromegaly with primary empty sella (ES), which is considered to be a rare association, and the impact of ES on the laboratory, radiological and prognostic status of acromegaly.

DESIGN

Acromegaly patients diagnosed and followed-up between 2012 and 2021 were included. Empty sella was defined as the pituitary gland and adenoma filling <50% of the sella turcica on preoperative T1 magnetic resonance imaging (MRI).

RESULTS

102 acromegalic patients (45 male, 57 female, 45.5 ± 12.8 (range: 20-70 years) were included and data of a median 3 years (range: 0.5-9 years) were presented. ES was detected in 19 (18.6%) patients and 4 had complete and 15 had partial ES. Although not significant, adenoma size and residual adenoma on MRI on postoperative 3rd month, and disease remission at last control were lower in acromegaly with ES than in acromegaly without ES, while the rate of female gender and remission on postoperative 3rd month were higher. While preoperative serum prolactin and nadir GH responses to OGTT were significantly lower in patients with ES, there was no difference in terms of other pituitary hormones among both groups.

CONCLUSION

The present study revealed the coexistence of newly diagnosed acromegaly with primary ES at a rate of nearly 20% which is more frequent than expected and this association is not rare. The presence of ES was not associated with any preoperative/postoperative pituitary hormone levels and remission status, except lower preoperative prolactin and nadir GH responses to OGTT.

Acromegaly with empty sella syndrome

SUMMARY

Acromegaly is a rare, chronic progressive disorder with characteristic clinical features caused by persistent hypersecretion of growth hormone (GH), mostly from a pituitary adenoma (95%). Occasionally, ectopic production of GH or growth hormone-releasing hormone (GHRH) with resultant GH hypersecretion may lead to acromegaly. Sometimes localizing the source of GH hypersecretion may prove difficult. Rarely, acromegaly has been found in patients with an empty sella (ES) secondary to prior pituitary radiation and/or surgery. However, acromegaly in patients with primary empty sella (PES) is exceeding rarely and has only been described in a few cases. We describe a 47-year-old male who presented with overt features of acromegaly (macroglossia, prognathism, increased hand and feet size). Biochemically, both the serum GH (21.6 μg/L) and insulin-like growth factor 1 (635 μg/L) were elevated. In addition, there was a paradoxical elevation of GH following a 75 g oral glucose load. Pituitary MRI demonstrated an ES. In order to exclude an ectopic source of GH hypersecretion, further biochemical tests and imaging were done, which were unremarkable. Notably, increased uptake in the sella turcica on the 68Gallium DOTATATE PET/CT confirmed the ES as the likely source of GH secretion. As no overt lesion was noted, medical treatment (octreotide acetate) was initiated with a good clinical and biochemical response. At his 3 month follow-up, he reported an improvement in symptoms (fatigue and headache), however he still complained of low libido. Due to a persistently low testosterone level at follow-up, a long-acting testosterone was initiated. His GH level normalised, and IGF-1 has significantly reduced.

LEARNING POINTS

The commonest cause of acromegaly is due to GH hypersecretion from pituitary adenomas (95%). Acromegaly has rarely been found in patients with ES. It is important to exclude a past history suggestive of pituitary apoplexy. Extra-pituitary source of GH such as ectopic production of GHRH with resultant GH hypersecretion needs to be excluded. In such cases, since there is no resectable mass, medical therapy is the primary treatment option.

Empty Sella Prevalence: Step By Step

An empty sella (ES), also known as an empty sella turcica (empty pituitary fossa) is defined as an intrasellar herniation of subarachnoid space within the sella which leads to flattening of the pituitary gland towards the posteroinferior wall. Purpose — to analyze studies of ES prevalence in the world. Methods — We carried out a systematic search in both Russian and English databases (E-library, PubMed, GoogleScholar, OxfordPress, ClinicalKeys) using keywords “empty sella”, “empty sella turcica”, “empty pituitary fossa”, “prevalence” and their combinations. The period of search: 2000-2020. It is also worth noting that earlier publications of historical interest were included in the review. Results — We have analyzed 23 studies. They can be roughly devided into two groups: the first group – screening studies of ES, the second group – targeted studies of ES.

Association of an empty sella and grave´s disease in a patient with acromegaly: a case report

Acromegaly is, in most cases, caused by growth hormone secreting pituitary adenomas. Those patients often develop different pathologies of the thyroid gland, however, the occurrence of Grave´s disease is quite a rare situation. We report a case of a 64-year-old female patient who presented with signs of hyperthyroidism and imbalance of her diabetes mellitus. On physical examination, she had facial features of acromegaly. Biochemical testing confirmed the suspicion of acromegaly and Grave´s disease, with an elevated insulin-like growth factor-1 and a suppressed thyroid stimulation hormone (TSH) with positive TSH-receptor antibodies. A pituitary Magnetic Resonance Imaging (MRI) was performed, revealing a macro-adenoma and an empty sella. The patient successfully underwent a transsphenoidal surgery and obtained a remission of her hyperthyroidism under anti-thyroid drugs.

Diagnosis, treatment and follow-up of patients with acromegaly in a clinical practice setting in Spain: the ACROPRAXIS program Delphi survey

AIM

The ACROPRAXIS program aims to describe the management of acromegaly in Spain and provide guidance.

METHODS

Ninety-three endocrinologists were organized into 13 panels to discuss the practical issues in managing acromegaly. Based on the key learnings, an online Delphi survey with 62 statements was performed, so those statements achieving consensus could be used as guidance. Statements were rated on a 9-point scale (9, full agreement; consensus > 66.6% of response in the same tertile).

RESULTS

Ninety-two endocrinologists (98.8%) answered two rounds of the survey (mean age 47.6 years; 59.8% women; median 18.5 years of experience). Consensus was achieved for 49 (79%) statements.

DIAGNOSIS

The levels of insulin-like growth factor I (IGFI) is the preferred screening test. If IGFI levels 1-1.3 ULN, the test is repeated and growth hormone (GH) after oral glucose tolerance test (OGTT) is assessed. A pituitary magnetic resonance is performed after biochemical diagnosis.

TREATMENT

Surgery is the first treatment choice for patients with microadenoma or macroadenoma with/without optical pathway compression. Pre-surgical somatostatin analogues (SSA) are indicated when surgery is delayed and/or to reduce anaesthesia-associated risks. After unsuccessful surgery, reintervention is performed if the residual tumor is resectable, while if non-resectable, SSA are administered. Follow-up First biochemical and clinical controls are performed 1-3 months after surgery. Disease remission is considered if random GH levels are < 1 µg/L or OGTT is < 1 or ≤ 0.4 µg/L, depending on the assay's sensitivity.

CONCLUSION

Current clinical management for acromegaly is homogeneous across Spain and generally follows clinical guidelines.

Quantification of specific growth patterns and frequency of the empty sella phenomenon in growth hormone-secreting pituitary adenomas

PURPOSE

To assess and quantify the prevalence and co-occurence of a sellar floor lowering and empty sella phenomenon in patients with GH (growth hormone)-secreting pituitary adenoma.

METHODS

A total number of 159 acromegalic patients were included in this study, as well as two control groups (150 patients with non-GH-secreting adenomas and 50 patients without pituitary adenomas). Magnetic resonance images of all patients were evaluated for presence of an empty sella, downward and lateral tumor extension, and maximum superoinferior diameter of the mass. Additionally, these values were correlated with growth hormone and IGF-1 levels.

RESULTS

The empty sella phenomenon was detected significantly more often in patients with a GH-secreting adenoma with a prevalence of 22% vs. 5.3% in non-GH-secreting adenomas (p < 0.001) or 8% in the healthy control group (p = .036). Moreover, GH-secreting adenomas presented with a significant rate of downward tumor extension (74.8% vs. 35.5%; p < 0.001), whose extent correlated inversely but weakly with the GH hormone level (r = - 0.17; p = .036). It was also found that a decreased superoinferior diameter and higher ratio of intrasellar to suprasellar extension are predictive quantitative values for the presence of a GH-secreting adenoma (area under curve, 0.712).

CONCLUSIONS

GH-secreting pituitary adenomas are frequently associated with an empty sella phenomenon. Moreover, GH-secreting adenomas are frequently accompanied by an enhanced, quantitatively measurable impression of the sellar floor. Hypothetically, this is caused by tumor-induced local bone remodeling processes.

Clinical characteristics of acromegalic patients with empty sella and their outcomes following transsphenoidal surgery

PURPOSE

To analyze the clinical characteristics of acromegalic patients with empty sella (ES, herniation of the subarachnoid space within the sella turcica) and the impact of ES on transsphenoidal surgery in such patients.

METHODS

Seventy-eight patients, newly diagnosed with acromegaly who underwent transsphenoidal surgery were included. ES was defined as the pituitary gland and adenoma occupying less than 50% of the sella turcica on midsagittal magnetic resonance (MR) imaging.

RESULTS

Twelve patients (15.4%), predominantly female (10 women, p = .047), had ES in preoperative MR imaging. ES patients had smaller mean tumor diameter (6.3 mm) than non-ES patients (11.2 mm, p = .001). In preoperative MR imaging, occult adenoma was found in three (25%) ES and three (4.5%) non-ES patients (p = .044). Intraoperative cerebrospinal fluid (CSF) leakage was more frequent in the ES patients than in the non-ES patients (58.3 vs. 25.8%, p = .024). This led to an increased rate of sellar floor reconstruction using abdominal fat and/or postoperative lumber drainage in the ES patients (ES: 41.7 vs. non-ES: 16.7%, p = .063). Endocrinological remission after surgery was more frequent in the non-ES patients (72.7%) than in the ES patients (58.3%) (p = .248).

CONCLUSIONS

Co-existence of acromegaly with ES is not rare, and is associated with occult adenoma, intra/postoperative CSF leakage, and a worse endocrinological outcome after transsphenoidal surgery; although, the underlying mechanism remains unclear.

Serum AGR2 as a useful biomarker for pituitary adenomas

OBJECTIVE

This study aims to evaluate whether the serum Anterior Gradient-2 (AGR2) can be used as a potential biomarker screening in the diagnosis of Pituitary adenomas(PAs).

PATIENTS AND METHODS

The serum AGR2 protein levels were preoperatively measured in 163 PA patients, 43 patients with other sellar lesions excluding PAs, 7 patients with prostate cancer as a positive control and 20 normal people(10 female and 10 male) using Enzyme-Linked ImmunoSorbent Assay (ELISA). Differences in the serum AGR2 level between different groups were analyzed for statistical significance with a Mann-Whitney U test.

RESULTS

The data showed that serum AGR2 level was significantly higher in the serum of PA patients (250.10±79.14ng/ml) than the patients with other sellar lesions (220.84±79.62ng/ml, P=0.017) and normal people (163.67±50.38ng/ml, P <0.001). Receiver operating characteristic (ROC) curve analysis was used. The detected area under the curve (AUC) was 0.835. The calculated optimal cut-off point for AGR2 level in serum samples was 158.63ng/ml (Youden index=0.564). The sensitivity was 91.4% and the specificity was 65.0%. Despite the variety of PA clinical features, the serum level of AGR2 are definite in PAs, although there may be a difference between male or female patients.

CONCLUSION

Our data suggests AGR2 as a potential biomarker for the diagnosis of PAs.

Ectopic Pituitary Adenomas Presenting as Sphenoid or Clival Lesions: Case Series and Management Recommendations

Background An ectopic pituitary adenoma presenting as a clival or sphenoid mass is a rare clinical occurrence that may mislead the clinician and result in unnecessary interventions or potential medicolegal consequences. Here, we present one of the largest multi-institutional case series and review the literature with an emphasis on radiological findings and critical preoperative workup. Methods Retrospective chart review. Results Nine patients were identified with ectopic pituitary adenomas of the sphenoid or clivus. There were four females and five males. Median age was 60 years old (range, 36-73 years). The most common presenting symptom was headache (56%). Five (56%) patients presented with a mass arising from the clivus while four (44%) presented with a mass in the sphenoid. Six (67%) patients demonstrated biochemical evidence of hypersecretion on full endocrinology panel. All masses showed evidence of enhancement with gadolinium with a propensity for adjacent bone involvement. Lesions also had a predilection for growth toward the cavernous sinus, carotid artery, or sellar floor. Surgical intervention was performed in eight patients (89%). In eight patients (89%), tumors demonstrated immunoreactivity to prolactin. Conclusions Pituitary adenomas can rarely present as an isolated sphenoid or clival mass. Lesions displayed similar magnetic resonance imaging findings with an erosive growth pattern toward the sellar floor, cavernous sinus, or adjacent carotid artery. Patients with clival or parasellar lesions with comparable features should have a preoperative workup which includes prolactin level and alert the physician to consider an ectopic pituitary adenoma in the differential to prevent unnecessary surgery and potential complications.

Developmental and Functional Effects of Steroid Hormones on the Neuroendocrine Axis and Spinal Cord

This review highlights the principal effects of steroid hormones at central and peripheral levels in the neuroendocrine axis. The data discussed highlight the principal role of oestrogens and testosterone in hormonal programming in relation to sexual orientation, reproductive and metabolic programming, and the neuroendocrine mechanism involved in the development of polycystic ovary syndrome phenotype. Moreover, consistent with the wide range of processes in which steroid hormones take part, we discuss the protective effects of progesterone on neurodegenerative disease and the signalling mechanism involved in the genesis of oestrogen-induced pituitary prolactinomas.