Corticotroph tumor progression after bilateral adrenalectomy (Nelson's syndrome): systematic review and expert consensus recommendations

Cushing syndrome

Cushing syndrome (CS) is a constellation of signs and symptoms caused by excessive exposure to exogenous or endogenous glucocorticoid hormones. Endogenous CS is caused by increased cortisol production by one or both adrenal glands (adrenal CS) or by elevated adrenocorticotropic hormone (ACTH) secretion from a pituitary tumour (Cushing disease (CD)) or non-pituitary tumour (ectopic ACTH secretion), which stimulates excessive cortisol production. CS is associated with severe multisystem morbidity, including impaired cardiovascular and metabolic function, infections and neuropsychiatric disorders, which notably reduce quality of life. Mortality is increased owing to pulmonary emboli, infection, myocardial infarction and cerebrovascular accidents. The clinical presentation is variable and because some CS signs and symptoms are common in the general population, the diagnosis might not be considered until many features have accumulated. Guidelines recommend screening patients with suspected CS with 24-h urine cortisol, bedtime salivary cortisol and/or 1 mg dexamethasone suppression test. Subsequently, determining the aetiology of CS is important as it affects management. The first-line therapy for all aetiologies of endogenous CS is surgical resection of the causal tissue, including corticotroph adenoma or ectopic tumour for ACTH-dependent CS or unilateral or bilateral adrenalectomy for adrenal CS. Second-line therapies include steroidogenesis inhibitors for any cause of CS, pituitary radiation (with or without steroidogenesis inhibitors) for CD, and bilateral adrenalectomy for ACTH-dependent causes of CS.

Diagnostic and management challenges in paediatric Cushing's syndrome

OBJECTIVE

Cushing syndrome (CS) is the result of chronic exposure to glucocorticoid excess. CS in children is most often caused by the administration of exogenous steroids. Endogenous CS is rare in the paediatric population and is caused mainly by tumours of the pituitary and adrenal glands, with ectopic sources being extraordinarily rare before the age of 18 years. In addition, children and young adults with CS present with different epidemiology, management issues, prognosis and outcomes than older adult patients. This complex disorder needs early diagnosis and management to avoid the significant morbidity and even mortality that can result from chronic untreated CS.

METHODS

In this review, we present the complex case of a 7-year-old boy with CS that highlights the diagnostic and management challenges of paediatric CS patients, including the considerations for genetic predisposition and life-long consequences of CS in children and young adults.

RESULTS

The diagnostic protocols for the evaluation of CS have been devised for adults and tested predominantly on adults. In this review, we discuss necessary modifications so that the testing can be adjusted for use in children. Additionally, pituitary adenomas in children are generally smaller and thus more difficult to recognize on pituitary imaging.

CONCLUSIONS

The management of the case and its complexities underline the need for children with CS to be managed in a centre with experienced paediatric endocrinologists and skilled neurosurgeons both for their initial diagnosis and treatment as well as for their long-term follow-up and management.

From Nelson's Syndrome to Corticotroph Tumor Progression Speed: An Update

Since the first description of Nelson syndrome 60 years ago, the way to consider corticotroph pituitary neuroendocrine tumors (PitNETs) after bilateral adrenalectomy has evolved. Today, it is globally acknowledged that only a subset of corticotroph PitNETs is aggressive.After adrenalectomy, corticotroph tumor progression (CTP) occurs in about 30 to 40% of patients during a median follow-up of 10 years. When CTP occurs, various CTP speeds (CTPS) can be observed. Using simple metrics in patients with CTP, CTPS was reported to vary from a few millimeters to up to 40 mm per year. Rapid CTPS/ Nelson's syndrome was associated with more severe Cushing's disease, higher adrenocorticotropic hormone (ACTH) in the year following adrenalectomy, and higher Ki67 on pituitary pathology. Complications such as apoplexy, cavernous syndrome, and visual defects were associated with higher CTPS. During follow-up, early morning ACTH, absolute variations properly reflected CTPS. Finally, CTPS was not higher after than before adrenalectomy, suggesting that cortisol deprivation after adrenalectomy does not impact CTPS in a majority of patients.Taken together, rapid CTPS/ Nelson's syndrome probably reflects the intrinsic aggressiveness of some corticotroph PitNETs. The precise molecular mechanisms related to corticotroph PitNET aggressiveness remain to be deciphered. Regular MRIs combined with intermediate morning ACTH measurements probably provide a reliable way to detect early and manage fast-growing tumors and, therefore, limit the complications.

Insights on epidemiology, morbidity and mortality of Cushing's disease in Northern Ireland

Cushing's disease is a rare condition that occurs due to an adrenocorticotrophin-producing corticotrophinoma arising from the pituitary gland. The consequent hypercortisolaemia results in multisystem morbidity and mortality. This study aims to report incidence, clinicopathological characteristics, remission outcomes and mortality in a regional pituitary neurosurgical cohort of patients diagnosed with Cushing's disease in Northern Ireland (NI) from 2000 to 2019. Clinical, biochemical and radiological data from a cohort of patients operated for Cushing's disease were retrospectively collected and analysed. Fifty-three patients were identified, resulting in an estimated annual incidence of Cushing's disease of 1.39-1.57 per million population per year. Females accounted for 72% (38/53) of the cohort. The majority (74%, 39/53) of corticotrophinomas were microadenomas and in 44% (17/39) of these no tumour was identified on preoperative magnetic resonance imaging. Histopathological characterisation was similarly difficult, with no tumour being identified in the histopathological specimen in 40% (21/53) of cases. Immediate postoperative remission rates were 53% and 66% when considering serum morning cortisol cut-offs of ≤ 50 nmol/L (1.8 µg/dL) and ≤ 138 nmol/L (5 µg/dL), respectively, in the week following pituitary surgery. Approximately 70% (37/53) of patients achieved longer-term remission with a single pituitary surgery. Three patients had recurrent disease. Patients with Cushing's disease had a significantly higher mortality rate compared to the NI general population (standardised mortality ratio 8.10, 95% CI 3.3-16.7, P < 0.001). Annual incidence of Cushing's disease in NI is consistent with other Northern European cohorts. Functioning corticotrophinomas are a clinically, radiologically and histopathologically elusive disease with increased mortality compared to the general population.

How to manage Cushing's disease after failed primary pituitary surgery

The first-line treatment for Cushing's disease is transsphenoidal adenomectomy, which can be curative in a significant number of patients. The second-line options in cases of failed primary pituitary surgery include repeat surgery, medical therapy, and radiation. The role for medical therapy has expanded in the last decade, and options include pituitary-targeting drugs, steroid synthesis inhibitors, and glucocorticoid receptor antagonists. Bilateral adrenalectomy is a more aggressive approach, which may be necessary in cases of persistent hypercortisolism despite surgery, medical treatment, or radiation or when rapid normalization of cortisol is needed. We review the available treatment options for Cushing's disease, focusing on the second-line treatment options to consider after failed primary pituitary surgery.

How often should we perform magnetic resonance imaging (MRI) for the follow-up of pituitary adenoma?

Magnetic resonance imaging (MRI) is the examination of choice for diagnosing and monitoring pituitary adenoma (also known as pituitary neuroendocrine tumor or PitNET), whether treated or not. However, repeating the examination too often (and sometimes unnecessarily) is costly, and worrying data on tissue accumulation (brain, bone, etc.) of gadolinium atoms dissociated from their carrier molecule (chelator) have led European authorities to ban contrast agents based on linear chelators of gadolinium, which are particularly susceptible to rapid dissociation, in favor of chemically more stable macrocyclic chelators. It is therefore important to determine the optimal frequency for pituitary MRI monitoring in order to safely assess the natural history or therapeutic response of pituitary adenomas. The aim of this article is to summarize the most recent data on optimal follow-up intervals depending on the type, size and location of the pituitary tumor and the clinical situation in general, in order to generate monitoring algorithms to guide clinicians.

Consensus guideline for the diagnosis and management of pituitary adenomas in childhood and adolescence: Part 2, specific diseases

Pituitary adenomas are rare in children and young people under the age of 19 (hereafter referred to as CYP) but they pose some different diagnostic and management challenges in this age group than in adults. These rare neoplasms can disrupt maturational, visual, intellectual and developmental processes and, in CYP, they tend to have more occult presentation, aggressive behaviour and are more likely to have a genetic basis than in adults. Through standardized AGREE II methodology, literature review and Delphi consensus, a multidisciplinary expert group developed 74 pragmatic management recommendations aimed at optimizing care for CYP in the first-ever comprehensive consensus guideline to cover the care of CYP with pituitary adenoma. Part 2 of this consensus guideline details 57 recommendations for paediatric patients with prolactinomas, Cushing disease, growth hormone excess causing gigantism and acromegaly, clinically non-functioning adenomas, and the rare TSHomas. Compared with adult patients with pituitary adenomas, we highlight that, in the CYP group, there is a greater proportion of functioning tumours, including macroprolactinomas, greater likelihood of underlying genetic disease, more corticotrophinomas in boys aged under 10 years than in girls and difficulty of peri-pubertal diagnosis of growth hormone excess. Collaboration with pituitary specialists caring for adult patients, as part of commissioned and centralized multidisciplinary teams, is key for optimizing management, transition and lifelong care and facilitates the collection of health-related quality of survival outcomes of novel medical, surgical and radiotherapeutic treatments, which are currently largely missing.

Seliciclib: A New Treatment for Cushing's Disease?

Previous studies have suggested that corticotroph tumours are associated with the overexpression of cyclin E and that the inactivation of cyclin-dependent kinases, which activate cyclin E, may have antisecretory and antiproliferative effects. Seliciclib, also known as R-roscovitine, is a pituitary-targeting agent shown to inhibit the growth of corticotroph tumour cells via cyclin E and retinoblastoma protein-mediated pathways. A recent study investigated the role of seliciclib in regulating biochemical parameters in a small number of patients with Cushing's disease, providing preliminary data on its possible therapeutic effectiveness in treating this disorder.

Discontinuation of Drug Treatment in Cushing's Disease Not Cured by Pituitary Surgery

OBJECTIVE

When transsphenoidal surgery (TSS) does not cure Cushing's disease (CD), 4 treatments are available: drug treatment (DT), second TSS (2nd TSS), bilateral adrenalectomy (BA), and pituitary radiotherapy (PR). DT is attractive but supposes long-term continuation, which we aimed to evaluate.

DESIGN AND METHODS

Retrospective study, in a center prioritizing 2nd TSS, of 36 patients, including 19 with TSS failure and 17 with recurrence, out of 119 patients with CD treated by a first TSS, average follow-up 6.1 years (95% confidence interval 5.27-6.91). Control was defined as normalization of urinary free cortisol (UFC) and final treatment (FT) as the treatment allowing control at last follow-up. We also analyzed discontinuation rates of DT in published CD prospective clinical trials.

RESULTS

Control was achieved in 33/36 patients (92%). DT was initiated in 29/36 patients (81%), allowing at least 1 normal UFC in 23/29 patients (79%) but was discontinued before last follow-up in 18/29 patients (62%). DT was FT in 11/29 patients (38%), all treated with cortisol synthesis inhibitors. Second TSS was FT in 8/16 (50%), BA in 14/14 (100%), and PR in 0/5. In published trials, discontinuation of DT was 11% to 51% at 1 year and 32% to 74% before 5 years.

CONCLUSION

DT allowed at least 1 normal UFC in 23/29 patients (79%) but obtained long-term control in only 11/29 (38%), as discontinuation rate was high, although similar to published data. Interestingly, a successful 2nd TSS was the cause for discontinuing efficient and well-tolerated DT in 5 patients. Further studies will show whether different strategies with cortisol synthesis inhibitors may allow for a lower discontinuation rate in patients not candidates for a 2nd TSS so that BA may be avoided in these patients.

Surveillance Imaging Strategies for Pituitary Adenomas: When, How Frequent, and When to Stop

OBJECTIVE

To describe a practical approach of when and how often to perform imaging, and when to stop imaging pituitary adenomas (PAs).

METHODS

A literature review was carried out and recommendations provided are derived largely from personal experience.

RESULTS

Magnetic resonance imaging is the mainstay imaging modality of choice in the assessment, treatment planning, and follow-up of PAs. These adenomas are discovered incidentally during imaging for a variety of unrelated conditions, because of clinical symptoms related to mass effects on the adjacent structures, or during workup for functional alterations of the adenoma. Imaging is also used in the preoperative and postoperative phases of assessment of PAs, for surgical and radiotherapy planning, for postoperative surveillance to assess for adenoma stability and detection of adenoma recurrence, and for surveillance to monitor for adenoma growth in unoperated PAs. Currently, because there are no evidence-based consensus recommendations, the optimal strategy for surveillance imaging of PAs is not clearly established. Younger age, initial adenoma size, extrasellar extension, mass effect, cavernous sinus invasion, functional status, histopathologic characteristics, cost considerations, imaging accessibility, patient preference, and patient contraindications (eg, implanted metallic devices and patient claustrophobia) are all important factors that influence the strategy for surveillance imaging.

CONCLUSIONS

This review provides a practical approach of performing surveillance imaging strategies for PAs that should be individualized based on clinical presentation, history, adenoma morphology on imaging, and histopathologic characteristics.

Paediatric Cushing's disease: long-term outcome and predictors of recurrence

Paediatric Cushing's disease (CD) is characterized by excess ACTH secretion from a pituitary adenoma, leading to hypercortisolism. It has approximately 5% of the incidence of adult CD and is a rare disorder in the paediatric age range. The four most specific presenting features of hypercortisolism are: change in facial appearance, weight gain, decreased linear growth and virilisation shown by advanced pubic hair for the stage of breast development or testicular volume. The main diagnostic priority is the demonstration of hypercortisolism followed by distinction between its ACTH-dependent and ACTH-independent origin, thus leading to identification of aetiology. All treatment options aim to resolve or control hypercortisolism. Consensus favours transsphenoidal (TSS) pituitary surgery with selective removal of the corticotroph adenoma. TSS in children with CD is now well established and induces remission in 70-100% of cases. External pituitary radiotherapy and bilateral adrenalectomy are second-line therapeutic approaches in subjects not responding to TSS. Long-term medical treatment is less frequently adopted. Recurrence in paediatric CD cases is low with factors predicting relapse being higher post-TSS cortisol and ACTH levels and rapid recovery of the hypothalamic-pituitary-adrenal axis after TSS. In summary, complete excision of the microadenoma with histological and biochemical evidence for this, predicts a low rate of recurrence of CD. Due to the need for rapid diagnosis and management to avoid the burden of prolonged exposure to hypercortisolism, tertiary university centres comprising both paediatric and adult endocrinology specialists together with experienced pituitary surgery and, eventually, radiotherapy units are recommended for referral of these patients.

Cushing's syndrome

Endogenous Cushing's syndrome results from excess glucocorticoid secretion, which leads to a myriad of clinical manifestations, comorbidities, and increased mortality despite treatment. Molecular mechanisms and genetic alterations associated with different causes of Cushing's syndrome have been described in the last decade. Imaging modalities and biochemical testing have evolved; however, both the diagnosis and management of Cushing's syndrome remain challenging. Surgery is the preferred treatment for all causes, but medical therapy has markedly advanced, with new drug options becoming available. Nevertheless, several comorbidities remain even after patient remission, which can affect quality of life. Accurate and timely diagnosis and treatment are essential for mitigating chronic complications of excess glucocorticoids and improving patient quality of life. In this Seminar, we aim to update several important aspects of diagnosis, complications, and treatment of endogenous Cushing's syndrome of all causes.

Complications and mortality of Cushing's disease: report on data collected over a 20-year period at a referral centre

CONTEXT

Cushing's disease (CD) is rare condition burdened by several systemic complications correlated to higher mortality rates. The primary goal of clinicians is to achieve remission, but it is unclear if treatment can also increase life expectancy.

AIM

To assess the prevalence of cortisol-related complications and mortality in a large cohort of CD patients attending a single referral centre.

MATERIALS AND METHODS

The clinical charts of CD patients attending a referral hospital between 2001 and 2021 were reviewed.

RESULTS

126 CD patients (median age at diagnosis 39 years) were included. At the last examination, 78/126 (61.9%) of the patients were in remission regardless of previous treatment strategies. Patients in remission showed a significant improvement in all the cardiovascular (CV) comorbidities (p < 0.05). The CV events were more frequent in older patients (p = 0.003), smokers and persistent CD groups (p < 0.05). Most of the thromboembolic (TE) and infective events occurred during active stages of the disease. The CV events were the most frequent cause of death. The standardized mortality ratio (SMR) resulted increased in persistent cases at the last follow-up (SMR 4.99, 95%CI [2.15; 9.83], p < 0.001) whilst it was not higher in those in remission (SMR 1.66, 95%CI [0.34; 4.85], p = 0.543) regardless of the timing or number of treatments carried out. A younger age at diagnosis (p = 0.005), a microadenoma (p = 0.002), and remission status at the last follow-up (p = 0.027) all increased survival. Furthermore, an elevated number of comorbidities, in particular arterial hypertension, increased mortality rates.

CONCLUSIONS

Patients with active CD presented a poor survival outcome. Remission restored the patients' life expectancy regardless of the timing or the types of treatments used to achieve it. Persistent CD-related comorbidities remained major risk factors.

An individualized approach to the management of Cushing disease

Cushing disease caused by an adrenocorticotropic hormone (ACTH)-secreting pituitary corticotroph adenoma leads to hypercortisolaemia with high mortality due to metabolic, cardiovascular, immunological, neurocognitive, haematological and infectious conditions. The disorder is challenging to diagnose because of its common and heterogenous presenting features and the biochemical pitfalls of testing levels of hormones in the hypothalamic-pituitary-adrenal axis. Several late-night salivary cortisol and 24-h urinary free cortisol tests are usually required as well as serum levels of cortisol after a dexamethasone suppression test. MRI might only identify an adenoma in 60-75% of patients and many adenomas are small. Therefore, inferior petrosal sinus sampling remains the gold standard for confirmation of ACTH secretion from a pituitary source. Initial treatment is usually transsphenoidal adenoma resection, but preoperative medical therapy is increasingly being used in some countries and regions. Other management approaches are required if Cushing disease persists or recurs following surgery, including medications to modulate ACTH or block cortisol secretion or actions, pituitary radiation, and/or bilateral adrenalectomy. All patients require lifelong surveillance for persistent comorbidities, clinical and biochemical recurrence, and treatment-related adverse effects (including development of treatment-associated hypopituitarism). In this Review, we discuss challenges in the management of Cushing disease in adults and provide information to guide clinicians when planning an integrated and individualized approach for each patient.

Aggressive Pituitary Tumors and Pituitary Carcinomas: From Pathology to Treatment

Aggressive pituitary tumors (APTs) and pituitary carcinomas (PCs) are heterogeneous with regard to clinical presentation, proliferative markers, clinical course, and response to therapy. Half of them show an aggressive course only many years after the first apparently benign presentation. APTs and PCs share several properties, but a Ki67 index greater than or equal to 10% and extensive p53 expression are more prevalent in PCs. Mutations in TP53 and ATRX are the most common genetic alterations; their detection might be of value for early identification of aggressiveness. Treatment requires a multimodal approach including surgery, radiotherapy, and drugs. Temozolomide is the recommended first-line chemotherapy, with response rates of about 40%. Immune checkpoint inhibitors have emerged as second-line treatment in PCs, with currently no evidence for a superior effect of dual therapy compared to monotherapy with PD-1 blockers. Bevacizumab has resulted in partial response (PR) in few patients; tyrosine kinase inhibitors and everolimus have generally not been useful. The effect of peptide receptor radionuclide therapy is limited as well. Management of APT/PC is challenging and should be discussed within an expert team with consideration of clinical and pathological findings, age, and general condition of the patient. Considering that APT/PCs are rare, new therapies should preferably be evaluated in shared standardized protocols. Prognostic and predictive markers to guide treatment decisions are needed and are the scope of ongoing research.

Refractory corticotroph adenomas

The majority of corticotroph adenomas are benign but some are locally invasive, demonstrate high rates of recurrence, and exhibit a relatively poor response to often repeated surgical, medical, and radiation treatment. Herein, we summarize the currently known somatic and genetic mutations and other molecular factors that influence the pathogenesis of these tumors and discuss currently available therapies. Although recent molecular studies have advanced our understanding of the pathogenesis and behavior of these refractory corticotroph adenomas, these insights do not reliably guide treatment choices at present. Development of additional diagnostic tools and novel tumor-directed therapies that offer efficacious treatment choices for patients with refractory corticotroph adenomas are needed.

Nelson's Syndrome: A Narrative Review

Nelson's syndrome (NS) is an uncommon disease occurring as a complication of bilateral adrenalectomy (BLA) in patients with persistent Cushing's disease (CD) due to an adrenocorticotropin-producing pituitary tumor. The first reports of this syndrome were done in the 50s, although its pathophysiology is still not understood. Every year, between 1.8 and 2.6 cases are thought to occur per million people. It is characterized by hyperpigmentation, elevated adrenocorticotropic hormone (ACTH) plasma levels, and typical signs and symptoms related to pituitary adenomas, such as visual deficits due to optic pathway compression or decreased hormone production from the adenohypophysis. NS represents a challenge due to the lack of accepted diagnostic criteria and the complexity of its treatment. Moreover, the development of stereotactic radiosurgery (SRS) in the last few years has become an essential but controversial strategy for this syndrome. This review presents a comprehensive overview of NS.

Knowing when to discontinue Temozolomide therapy in responding aggressive pituitary tumors and carcinomas: a systematic review and Padua (Italy) case series

INTRODUCTION

Pituitary adenomas can show a tendency to grow, despite multimodal treatment. Temozolomide (TMZ) has been used in the last 15 years in patients with aggressive pituitary tumors. TMZ requires a careful balance of different expertise, especially for selection criteria.

AREAS COVERED

We conducted: (1) a systematic review of the published literature from 2006 to 2022, collecting only cases with a complete description of patient follow-up after TMZ discontinuation; (2) a description of all patients with aggressive pituitary adenoma or carcinoma treated in Padua (Italy).

EXPERT OPINION

There is considerable heterogeneity in the literature: TMZ cycles duration ranged from 3 to 47 months; the follow-up time after TMZ discontinuation ranged from 4 to 91 months (mean 24 months, median 18 months), at least a stable disease has been reported in 75% of patients after a mean 13 months (range 3-47 months, median 10 months). The Padua (Italy) cohort reflects the literature. Future directions to explore are to understand the pathophysiological mechanism of TMZ resistance escape, to develop predicting factors to TMZ treatment (especially through the delineation of the underlying transformation processes), and to further expand the therapeutic applications of TMZ (as neoadjuvant, combined with radiotherapy).

Renin and electrolytes indicate the mineralocorticoid activity of fludrocortisone: a 6 year study in primary adrenal insufficiency

CONTEXT

Fludrocortisone (FC) is the mineralocorticoid (MC) replacement treatment for patients with primary adrenal insufficiency (PAI).

OBJECTIVE

To explore the dose of FC treatment and its relationship with glucocorticoid therapy, sodium, potassium, renin and clinical parameters.

SETTING

Monocentric cohort.

PATIENTS

Data of 193 patients with PAI (130 autoimmune) were collected during baseline (T0), intermediate (T1) and last follow-up visit (T2, respectively, after a mean of 38 and 72 months).

MAIN OUTCOME MEASURE

Utility of endocrine and clinical parameters to titrate FC dose.

RESULTS

FC dose (50-75 μg/daily) was stable in the follow-up in half patients. The MC activity of FC was dose-dependent: we observed a reduced but significant positive linear correlation between FC dose and sodium (r = 0.132) and negative linear correlation between FC and potassium (r = - 0.162) or renin (r = - 0.131, all p < 0.01). An overall reduction in the FC dose was observed at T2 in the group with longer follow-up (> 60 months, p < 0.05). Higher doses of FC were observed in patients with low-normal renin, especially in autoimmune PAI (86 vs 65 μg/daily, p < 0.05). On the contrary, reduced sodium and increased potassium levels were observed in patients with high renin at T2. The number of cardiovascular events (15 in the whole cohort) was similar in patients sorted by renin levels or FC dose.

CONCLUSIONS

Renin and electrolytes can indicate the MC activity of FC treatment: they should be routinely evaluated and used to titrate its dose that can be reduced in the long-term follow-up.

Corticotroph tumor progression speed after adrenalectomy

OBJECTIVES

After bilateral adrenalectomy in Cushing's disease, corticotroph tumor progression occurs in one-third to half of patients. However, progression speed is variable, ranging from slow to rapid. The aim was to explore corticotroph progression speed, its consequences and its risk factors.

DESIGN

A retrospective single-center observational study.

METHODS

In total,103 patients with Cushing's disease who underwent bilateral adrenalectomy between 1990 and 2020 were included. Clinical, biological, histological and MRI features were collected. Median duration of follow-up after bilateral adrenalectomy was 9.31 years.

RESULTS

In total,44 patients progressed (43%). Corticotroph tumor progression speed ranged from 1 to 40.7 mm per year. Progression speed was not different before and after bilateral adrenalectomy (P = 0.29). In univariate analyses, predictive factors for rapid corticotroph tumor progression included the severity of Cushing's disease before adrenalectomy as the cause of adrenalectomy, high ACTH in the year following adrenalectomy and high Ki67 immunopositivity in the tumor. During follow-up, early morning ACTH absolute variation was associated with corticotroph tumor progression speed (P-value = 0.001). ACTH measurement after dynamic testing did not improve this association.

CONCLUSION

After adrenalectomy, corticotroph progression speed is highly variable and manageable with MRI and ACTH surveillance. Progression speed does not seem related to bilateral adrenalectomy but rather to intrinsic properties of highly proliferative and secreting tumors.

Corticotroph tumor progression after bilateral adrenalectomy: data from ERCUSYN

Corticotroph tumor progression after bilateral adrenalectomy/Nelson's syndrome (CTP-BADX/NS) is a severe complication of bilateral adrenalectomy (BADX). The aim of our study was to investigate the prevalence, presentation and outcome of CTP-BADX/NS in patients with Cushing's disease (CD) included in the European Registry on Cushing's Syndrome (ERCUSYN). We examined data on 1045 CD patients and identified 85 (8%) who underwent BADX. Of these, 73 (86%) had follow-up data available. The median duration of follow-up since BADX to the last visit/death was 7 years (IQR 2-9 years). Thirty-three patients (45%) experienced CTP-BADX/NS after 3 years (1.5-6) since BADX. Cumulative progression-free survival was 73% at 3 years, 66% at 5 years and 46% at 10 years. CTP-BADX/NS patients more frequently had a visible tumor at diagnosis of CD than patients without CTP-BADX/NS (P < 0.05). Twenty-seven CTP-BADX/NS patients underwent surgery, 48% radiotherapy and 27% received medical therapy. The median time since diagnosis of CTP-BADX/NS to the last follow-up visit was 2 years (IQR, 1-5). Control of tumor progression was not achieved in 16 of 33 (48%) patients, of whom 8 (50%) died after a mean of 4 years. Maximum adenoma size at diagnosis of CD was associated with further tumor growth in CTP-BADX/NS despite treatment (P = 0.033). Diagnosis of CTP-BADX/NS, older age, greater UFC levels at diagnosis of CD and initial treatment predicted mortality. In conclusion, CTP-BADX/NS was reported in 45% of the ERCUSYN patients who underwent BADX, and control of tumor growth was reached in half of them. Future studies are needed to establish effective strategies for prevention and treatment.

Reoperation for Recurrent and Persistent Cushing's Disease without Visible MRI Findings

PURPOSE

Transsphenoidal surgery is the first-line treatment for Cushing's disease (CD), even with negative preoperative magnetic resonance imaging (MRI) results. Some patients with persistent or recurring hypercortisolism have negative MRI findings after the initial surgery. We aimed to analyze the efficacy of repeat surgery in two groups of patients and determine if there is an association between positive MRI findings and early remission.

PATIENTS AND METHODS

Clinical, imaging, and biochemical information of 42 patients who underwent repeat surgery by a single neurosurgeon between 2002 and 2021 was retrospectively analyzed. We compared the endocrinological, histopathological, and surgical outcomes before and after repeat surgery among 14 CD patients with negative MRI findings and 28 patients with positive MRI findings.

RESULTS

Immediate remission was achieved in 29 patients (69.0%) who underwent repeat surgery. Among all patients, 28 (66.7%) had MRI findings consistent with solid lesions. There was no significant difference in remission rates between the recurrence and persistence groups (77.8% vs. 57.1%, odds ratio = 2.625, 95% confidence interval = 0.651 to 10.586). Patients in remission after repeat surgery were not associated with positive MRI findings (odds ratio = 3.667, 95% confidence interval = 0.920 to 14.622).

CONCLUSIONS

In terms of recurrence, repeat surgery in patients with either positive or negative MRI findings showed reasonable remission rates. For persistent disease with positive MRI findings, repeat surgery is still an option; however, more solid evidence is needed to determine if negative MRI findings are predictors for failed reoperations for persistent hypercortisolism.

Management of Nelson’s Syndrome

Nelson’s syndrome is a potentially severe condition that may develop in patients with Cushing’s disease treated with bilateral adrenalectomy. Its management can be challenging. Pituitary surgery followed or not by radiotherapy offers the most optimal tumour control, whilst pituitary irradiation alone needs to be considered in cases requiring intervention and are poor surgical candidates. Observation is an option for patients with small lesions, not causing mass effects to vital adjacent structures but close follow-up is required for a timely detection of corticotroph tumour progression and for further treatment if required. To date, no medical therapy has been consistently proven to be effective in Nelson’s syndrome. Pharmacotherapy, however, should be considered when other management approaches have failed. A subset of patients with Nelson’s syndrome may develop further tumour growth after primary treatment, and, in some cases, a truly aggressive tumour behaviour can be demonstrated. In the absence of evidence-based guidance, the management of these cases is individualized and tailored to previously offered treatments. Temozolomide has been used in patients with aggressive Nelson’s with no consistent results. Development of tumour-targeted therapeutic agents are an unmet need for the management of aggressive cases of Nelson’s syndrome.

Diagnosis and management of hypertension in patients with Cushing's syndrome: a position statement and consensus of the Working Group on Endocrine Hypertension of the European Society of Hypertension

Endogenous/exogenous Cushing's syndrome is characterized by a cluster of systemic manifestations of hypercortisolism, which cause increased cardiovascular risk. Its biological basis is glucocorticoid excess, acting on various pathogenic processes inducing cardiovascular damage. Hypertension is a common feature in Cushing's syndrome and may persist after normalizing hormone excess and discontinuing steroid therapy. In endogenous Cushing's syndrome, the earlier the diagnosis the sooner management can be employed to offset the deleterious effects of excess cortisol. Such management includes combined treatments directed against the underlying cause and tailored antihypertensive drugs aimed at controlling the consequences of glucocorticoid excess. Experts on endocrine hypertension and members of the Working Group on Endocrine Hypertension of the European Society of Hypertension (ESH) prepared this Consensus document, which summarizes the current knowledge in epidemiology, genetics, diagnosis, and treatment of hypertension in Cushing's syndrome.

Cushing's disease: role of bilateral adrenalectomy

INTRODUCTION

Laparoscopic bilateral adrenalectomy (BAD) is one of the treatments of Cushing's Disease (CD), but its indications and outcome is debated.

METHODS

The literature on BAD was reviewed as part of a work performed for the Cushing's disease guideline.

RESULTS

The surgical morbidity of BAD is reported between 10 and 18% and no mortality has been reported in the largest series. Because of the endocrine sacrifice it will be mostly performed after a multidisciplinary team discussion in selected cases of refractory CD (mostly after failure of pituitary surgery and/or medical treatment). It is also frequently discussed in female patients desiring pregnancy. Corticotroph tumor progression occurs in 40% of the patients but is in most patients manageable when detected early by a careful long term monitoring with pituitary MRI and ACTH assays after BAD.

CONCLUSION

BAD is a safe and effective treatment of CD used in specific situations and requiring long term monitoring.

Aggressive pituitary tumours and carcinomas, characteristics and management of 171 patients

OBJECTIVE

To describe clinical and pathological characteristics and treatment outcomes in a large cohort of aggressive pituitary tumours (APT)/pituitary carcinomas (PC).

DESIGN

Electronic survey August 2020-May 2021.

RESULTS

96% of 171 (121 APT, 50 PC), initially presented as macro/giant tumours, 6 were microadenomas (5 corticotroph). Ninety-seven tumours, initially considered clinically benign, demonstrated aggressive behaviour after 5.5 years (IQR: 2.8-12). Of the patients, 63% were men. Adrenocorticotrophic hormone (ACTH)-secreting tumours constituted 30% of the APT/PC, and the gonadotroph subtypes were under-represented. Five out of 13 silent corticotroph tumours and 2/6 silent somatotroph tumours became secreting. Metastases were observed after median 6.3 years (IQR 3.7-12.1) from diagnosis. At the first surgery, the Ki67 index was ≥3% in 74/93 (80%) and ≥10% in 38/93 (41%) tumours. An absolute increase of Ki67 ≥ 10% after median of 6 years from the first surgery occurred in 18/49 examined tumours. Tumours with an aggressive course from outset had higher Ki67, mitotic counts, and p53. Temozolomide treatment in 156/171 patients resulted in complete response in 9.6%, partial response in 30.1%, stable disease in 28.1%, and progressive disease in 32.2% of the patients. Treatment with bevacizumab, immune checkpoint inhibitors, and peptide receptor radionuclide therapy resulted in partial regression in 1/10, 1/6, and 3/11, respectively. Median survival in APT and PC was 17.2 and 11.3 years, respectively. Tumours with Ki67 ≥ 10% and ACTH-secretion were associated with worse prognosis.

CONCLUSION

APT/PCs exhibit a wide and challenging spectrum of behaviour. Temozolomide is the first-line chemotherapy, and other oncological therapies are emerging. Treatment response continues to be difficult to predict with currently studied biomarkers.

TP53 mutations in functional corticotroph tumors are linked to invasion and worse clinical outcome

Corticotroph macroadenomas are rare but difficult to manage intracranial neoplasms. Mutations in the two Cushing's disease mutational hotspots USP8 and USP48 are less frequent in corticotroph macroadenomas and invasive tumors. There is evidence that TP53 mutations are not as rare as previously thought in these tumors. The aim of this study was to determine the prevalence of TP53 mutations in corticotroph tumors, with emphasis on macroadenomas, and their possible association with clinical and tumor characteristics. To this end, the entire TP53 coding region was sequenced in 86 functional corticotroph tumors (61 USP8 wild type; 66 macroadenomas) and the clinical characteristics of patients with TP53 mutant tumors were compared with TP53/USP8 wild type and USP8 mutant tumors. We found pathogenic TP53 variants in 9 corticotroph tumors (all macroadenomas and USP8 wild type). TP53 mutant tumors represented 14% of all functional corticotroph macroadenomas and 24% of all invasive tumors, were significantly larger and invasive, and had higher Ki67 indices and Knosp grades compared to wild type tumors. Patients with TP53 mutant tumors had undergone more therapeutic interventions, including radiation and bilateral adrenalectomy. In conclusion, pathogenic TP53 variants are more frequent than expected, representing a relevant amount of functional corticotroph macroadenomas and invasive tumors. TP53 mutations associated with more aggressive tumor features and difficult to manage disease.

The Role of Glucocorticoid Receptor in the Pathophysiology of Pituitary Corticotroph Adenomas

Adrenocorticotropic Hormone (ACTH)-secreting pituitary adenomas are rare tumors characterized by autonomous ACTH secretion with a consequent increase in circulating cortisol levels. The resulting clinical picture is called Cushing’s disease (CD), a severe condition burdened with high morbidity and mortality. Apart from increased cortisol levels, CD patients exhibit a partial resistance to the negative glucocorticoid (GC) feedback, which is of paramount clinical utility, as the lack of suppression after dexamethasone administration is one of the mainstays for the differential diagnosis of CD. Since the glucocorticoid receptor (GR) is the main regulator of negative feedback of the hypothalamic–pituitary–adrenal axis in normal conditions, its implication in the pathophysiology of ACTH-secreting pituitary tumors is highly plausible. In this paper, we review GR function and structure and the mechanisms of GC resistance in ACTH-secreting pituitary tumors and assess the effects of the available medical therapies targeting GR on tumor growth.

Glucocorticoid Withdrawal Syndrome following treatment of endogenous Cushing Syndrome

PURPOSE

Literature regarding endogenous Cushing syndrome (CS) largely focuses on the challenges of diagnosis, subtyping, and treatment. The enigmatic phenomenon of glucocorticoid withdrawal syndrome (GWS), due to rapid reduction in cortisol exposure following treatment of CS, is less commonly discussed but also difficult to manage. We highlight the clinical approach to navigating patients from GWS and adrenal insufficiency to full hypothalamic-pituitary-adrenal (HPA) axis recovery.

METHODS

We review the literature on the pathogenesis of GWS and its clinical presentation. We provide strategies for glucocorticoid dosing and tapering, HPA axis testing, as well as pharmacotherapy and ancillary treatments for GWS symptom management.

RESULTS

GWS can be difficult to differentiate from adrenal insufficiency and CS recurrence, which complicates glucocorticoid dosing and tapering regimens. Monitoring for HPA axis recovery requires both clinical and biochemical assessments. The most important intervention is reassurance to patients that GWS symptoms portend a favorable prognosis of sustained remission from CS, and GWS typically resolves as the HPA axis recovers. GWS also occurs during medical management of CS, and gradual dose titration based primarily on symptoms is essential to maintain adherence and to eventually achieve disease control. Myopathy and neurocognitive dysfunction can be chronic complications of CS that do not completely recover.

CONCLUSIONS

Due to limited data, no guidelines have been developed for management of GWS. Nevertheless, this article provides overarching themes derived from published literature plus expert opinion and experience. Future studies are needed to better understand the pathophysiology of GWS to guide more targeted and optimal treatments.

Consensus on diagnosis and management of Cushing's disease: a guideline update

Cushing's disease requires accurate diagnosis, careful treatment selection, and long-term management to optimise patient outcomes. The Pituitary Society convened a consensus workshop comprising more than 50 academic researchers and clinical experts to discuss the application of recent evidence to clinical practice. In advance of the virtual meeting, data from 2015 to present about screening and diagnosis; surgery, medical, and radiation therapy; and disease-related and treatment-related complications of Cushing's disease summarised in recorded lectures were reviewed by all participants. During the meeting, concise summaries of the recorded lectures were presented, followed by small group breakout discussions. Consensus opinions from each group were collated into a draft document, which was reviewed and approved by all participants. Recommendations regarding use of laboratory tests, imaging, and treatment options are presented, along with algorithms for diagnosis of Cushing's syndrome and management of Cushing's disease. Topics considered most important to address in future research are also identified.

Prevalence of Nelson's syndrome after bilateral adrenalectomy in patients with cushing's disease: a systematic review and meta-analysis

PURPOSE

Bilateral adrenalectomy (BA) still plays an important role in the management of Cushing's disease (CD). Nelson's syndrome (NS) is a severe complication of BA, but conflicting data on its prevalence and predicting factors have been reported. The aim of this study was to determine the prevalence of NS, and identify factors associated with its development.

DATA SOURCES

Systematic literature search in four databases.

STUDY SELECTION

Observational studies reporting the prevalence of NS after BA in adult patients with CD.

DATA EXTRACTION

Data extraction and risk of bias assessment were performed by three independent investigators.

DATA SYNTHESIS

Thirty-six studies, with a total of 1316 CD patients treated with BA, were included for the primary outcome. Pooled prevalence of NS was 26% (95% CI 22-31%), with moderate to high heterogeneity (I² 67%, P < 0.01). The time from BA to NS varied from 2 months to 39 years. The prevalence of NS in the most recently published studies, where magnet resonance imaging was used, was 38% (95% CI 27-50%). The prevalence of treatment for NS was 21% (95% CI 18-26%). Relative risk for NS was not significantly affected by prior pituitary radiotherapy [0.9 (95% CI 0.5-1.6)] or pituitary surgery [0.6 (95% CI 0.4-1.0)].

CONCLUSIONS

Every fourth patient with CD treated with BA develops NS, and every fifth patient requires pituitary-specific treatment. The risk of NS may persist for up to four decades after BA. Life-long follow-up is essential for early detection and adequate treatment of NS.

Gamma knife radiosurgery in patients with Nelson's syndrome

PURPOSE

Nelson's syndrome (NS) is a long-term complication of bilateral adrenalectomy in patients with Cushing's disease. The best therapeutic strategy in NS has not been well defined. Gamma knife radiosurgery (GKRS) is very effective to stop the growth of the pituitary adenoma, which is the main goal of the treatment of patients with NS. We report the largest series of patients with NS treated by GKRS at a single center.

METHODS

The study was an observational, retrospective analysis of 28 consecutive patients with NS treated by GKRS in our department between 1995 and 2019. All patients had a growing ACTH-secreting pituitary adenoma. The main outcome of the study was to assess by the Kaplan-Meier method the risk of tumor progression after GKRS.

RESULTS

The median follow-up after GKRS treatment was 98 months (IQR 61-155 months, range 7-250 months). Two patients (7.1%) had a recurrence of disease during follow-up. The 10-year progression-free survival was 91.7% (95% CI 80.5-100%). No patient had deterioration of visual function or oculomotor function after GKRS. New onset of hypogonadism and hypothyroidism occurred in 18.8% and 14.3% of the patients at risk.

CONCLUSION

Our study confirms that GKRS may stop the tumor growth in the majority of patients with NS, even though very aggressive adenomas may ultimately escape this treatment. Safety of GKRS was good in our experience, but due attention must be paid to planning the distribution of radiation to critical structures, especially in patients previously treated by radiation.