LONG-TERM OUTCOME OF THE DIFFERENT TREATMENT ALTERNATIVES FOR RECURRENT AND PERSISTENT CUSHING DISEASE

Venous Thromboembolism and Prevention Strategies in Patients with Cushing's Disease: A Systematic Review

BACKGROUND

There is a well-documented association between Cushing's syndrome (CS) and hypercoagulability. However, there is limited data on the risk of venous thromboembolic events (VTEs) after surgery for Cushing's disease (CD). There is no consensus on optimal postoperative anticoagulation strategies in this group. This review gathers information on the rates of VTE after surgery for CD, as well as reported prophylaxis strategies in this population.

METHODS

A literature search was performed using Cochrane Library, EMBASE, and Ovid MEDLINE databases according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A narrative review of papers discussing mechanisms of hypercoagulability in CS was conducted.

RESULTS

Twenty-five relevant papers were identified out of 944 papers yielded. Pooled postoperative VTE incidence in patients undergoing transsphenoidal surgery for CD was 2% (58 out of 2997). The pooled rate of VTE-associated mortality based on the 23 studies that reported this information was 0.2% (6 out of 2077). There were no cases of postoperative VTE in the 191 patients undergoing adrenalectomy for benign adrenocorticotropic hormone-independent CS. Ten studies reported information on perioperative thromboprophylaxis strategies in transsphenoidal surgery for CD and adrenalectomy for adrenocorticotropic hormone-independent CS.

CONCLUSIONS

Postoperative VTE in CD is a source of morbidity, with a rate of 2% and mortality rate of 0.2%, highlighting that surgical resection of the corticotroph adenoma does not necessarily result in immediate resolution of hypercoagulability. Increased production of coagulation factors, impaired fibrinolysis, inflammation, and CS-associated metabolic risk factors all factor into the pathogenesis of CS-associated hypercoagulability. Further study is needed on an optimal pharmacologic prophylaxis strategy.

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.

Ketoconazole as second-line treatment for Cushing's disease after transsphenoidal surgery: systematic review and meta-analysis

Introduction

The first-line treatment for Cushing's disease is transsphenoidal surgery for pituitary tumor resection. Ketoconazole has been used as a second-line drug despite limited data on its safety and efficacy for this purpose. The objective of this meta-analysis was to analyze hypercortisolism control in patients who used ketoconazole as a second-line treatment after transsphenoidal surgery, in addition to other clinical and laboratory criteria that could be related to therapeutic response.

Methods

We searched for articles that evaluated ketoconazole use in Cushing's disease after transsphenoidal surgery. The search strategies were applied to MEDLINE, EMBASE, and SciELO. Independent reviewers assessed study eligibility and quality and extracted data on hypercortisolism control and related variables such as therapeutic dose, time, and urinary cortisol levels.

Results

After applying the exclusion criteria, 10 articles (one prospective and nine retrospective studies, totaling 270 patients) were included for complete data analysis. We found no publication bias regarding reported biochemical control or no biochemical control (p = 0.06 and p = 0.42 respectively). Of 270 patients, biochemical control of hypercortisolism occurred in 151 (63%, 95% CI 50-74%) and no biochemical control occurred in 61 (20%, 95% CI 10-35%). According to the meta-regression, neither the final dose, treatment duration, nor initial serum cortisol levels were associated with biochemical control of hypercortisolism.

Conclusion

Ketoconazole can be considered a safe and efficacious option for Cushing's disease treatment after pituitary surgery.

Systematic review registration

https://www.crd.york.ac.uk/prospero/#searchadvanced, (CRD42022308041).

Recurrent Cushing Disease: An Extensive Review on Pros and Cons of Different Therapeutic Approaches

OBJECTIVE

Recurrent Cushing disease (CD) is characterized by the reappearance of clinical and hormonal aspects of hypercortisolism that occur more than 6 months after an initial post-treatment remission.

METHODS

We performed a systematic review and meta-analysis to synthesize the evidence about remission and complication rates after transsphenoidal surgery (TSS) radiotherapy (RT) and medical therapy (MT) in recurrent CD patients. A quantitative systematic review was performed. Article selection was performed by searching MEDLINE (using PubMed), and Cochrane electronic bibliographic databases through 2020.

RESULTS

We noted 61 articles described therapeutic management of recurrent CD patients with representative outcome. A total of 723 patients received different therapeutic modality for their recurrent CD. The remission rates were 0.65 (95% confidence interval [CI] 0.60-0.70), 0.57 (95% CI 0.51-0.63), and 0.75 (95% CI 0.60-0.86) in the TSS, RT, and MT subgroups, respectively. The total remission rate after therapeutic approaches on recurrent CD patients was 0.64 (95% CI 0.60-0.68). A test for subgroup differences revealed there was a statistically significant difference between different subgroups (P = 0.01). The post hoc test showed that in comparison with RT, TSS (P = 0.0344) and MT (P = 0.0149) had a higher rate of remission. However, there was no statistically significant difference between separate therapeutic modalities in terms of complications including diabetes insipidus (P = 1.0) and hypopituitarism (P = 0.28).

CONCLUSIONS

Compared MT and TSS, RT has a statistically lower rate of remission. Although there is robust superiority of surgery over RT, interpretation of MT data must considered with caution due to the small number of included cases and wide CI range.

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.

Recurrence Rate and Exploration of Clinical Factors after Pituitary Adenoma Surgery: A Systematic Review and Meta-Analysis based on Computer Artificial Intelligence System

Background

The first-line treatment for patients with any type of pituitary adenoma is trans-sphenoidal surgery. Considering the prevalence of the condition globally, the treatment is quite common. The recurrence of pituitary adenoma is a recognized occurrence in the medical field; however, there is limited comprehensive research and analysis of the predictive factors of recurrence rates and the clinical factors impacting relapse rates. Identifying the recurrence rates of pituitary adenomas and the clinical factors associated with them could help increase the remission rate by increasing focus on the specific aspects for early diagnosis and improved treatment.

Objective

The objective of the current systematic review and meta-analysis is to assess the recurrent rates based on previous studies and to explore the clinical factors after pituitary surgery.

Methods

A search was performed on PubMed, APA PsycINFO, Scopus, CENTRAL, and Google Scholar databases for English articles published from 1^st January 2010 to 1^st August 2022. Systematic reviews, meta-analysis, evidence syntheses, editorials, commentaries, preclinical studies, abstracts, theses, and preprints were excluded. Meta XL statistical software was used to conduct a prevalence meta-analysis.

Results

PubMed, PsycINFO, and Medline databases were searched. All of the articles were written between 2012 and 2022. In the beginning, 612 items were recognized. After removing duplicates and analyzing the remaining articles in terms of inclusion and exclusion criteria, 31 articles remained.

Conclusion

There is a relationship between recurrence rates and the follow-up period. There were conflicting results about the clinical factors after pituitary adenoma surgery, specifically age and tumor size. Some included studies that there was an association between macroadenomas and high recurrence rates. No study reported that gender was a clinical factor affecting pituitary adenoma surgery outcomes or the recurrence rate. Studies also reported that there was a correlation between the remnant tumor factor and the recurrence rates; adenoma remnants after surgery increased the risk of recurrence rates for patients.

Treatment of recurrent and persistent Cushing's disease after first transsphenoidal surgery: lessons learned from an international meta-analysis

PURPOSE

Transsphenoidal surgery (TSS) is the first-line treatment for patients with Cushing's Disease (CD). Recurrence rates after a first TSS range between 3 and 22% within 3 years. Management of recurrent or persistent CD may include repeat TSS or stereotactic radiosurgery (SRS). We performed a meta-analysis to explore the overall efficacy of TSS and SRS for patients with CD after an initial surgical intervention.

METHODS

EMBASE, PubMed, SCOPUS, and Cochrane databases were searched from their dates-of-inception up to December 2021. Inclusion criteria were comprised of patients with an established diagnosis of CD who presented with persistent or biochemically recurrent disease after a first TSS for tumor resection and were treated with a second TSS or SRS.

RESULTS

Search criteria yielded 2,116 studies of which 37 articles from 15 countries were included for analysis. Mean age ranged between 29.9 and 47.9 years, and mean follow-up was 11-104 months. TSS was used in 669 (67.7%) patients, while SRS was used in 320 (32.4%) patients, and remission rates for CD were 59% (95%CI 0.49-0.68) and 74% (95%CI 0.54-0.88), respectively. There was no statistically significant difference in the remission rate between TSS and SRS (P = 0.15). The remission rate of patients with recurrent CD undergoing TSS was 53% (95%CI 0.32-0.73), and for persistent CD was 41% (95%CI 0.28-0.56) (P = 0.36).

CONCLUSION

Both TSS and SRS are possible approaches for the treatment of recurrent or persistent CD after a first TSS. Our data show that either TSS or SRS represent viable treatment options to achieve remission for this subset of patients.

Low but not undetectable early postoperative nadir serum cortisol predicts sustained remission in Cushing's disease

Objective

Transsphenoidal surgery (TSS) is the first-line treatment for Cushing's disease. The objectives of the study were to determine remission and recurrence rates after TSS for Cushing's disease, identify factors that predict these outcomes, and define the threshold for postoperative morning serum cortisol (MSeC) that most accurately predicts sustained remission.

Methods

Records were retrospectively reviewed for consecutive adults undergoing TSS for Cushing's disease at a tertiary centre (1990-2019). Remission was defined as MSeC <138 nmol/L by 6 weeks postoperatively. Recurrence was defined as elevated 24-h urine free cortisol, lack of suppression after dexamethasone or elevated midnight salivary cortisol.

Results

In this study, 42 patients (age 47 ± 13 years, 83% female) were assessed with 55 ± 56 months of follow-up. Remission occurred after 77% of primary (n = 30) and 42% of revision operations (n = 12). After primary surgery, remission was associated with lower MSeC nadir (26 ± 36 nmol/L vs 347 ± 220 nmol/L, P  < 0.01) and lower adrenocorticotropin nadir (2 ± 3 pmol/L vs 6 ± 3 pmol/L, P = 0.01). Sustained remission 5 years after surgery was predicted by MSeC <92 nmol/L within 2 weeks postoperatively (sensitivity 100% and specificity 100%). After revision surgery, remission was predicted by lower MSeC nadir (70 ± 45 nmol/L vs 408 ± 305 nmol/L, P = 0.03), smaller tumour diameter (3 ± 2 mm vs 15 ± 13 mm, P = 0.05) and absence of cavernous sinus invasion (0% vs 71%, P = 0.03). Recurrence after primary and revision surgery occurred in 17% and 20% of patients respectively.

Conclusions

Lower postoperative MSeC nadir strongly predicted remission after both primary and revision surgery. Following primary surgery, an MSeC <92 nmol/L within 2 weeks predicted sustained remission at 5 years. MSeC nadir was the most important prognostic marker following TSS for Cushing's disease.

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.

Diabetes, Active Disease, and Afternoon Serum Cortisol Levels Predict Cushing's Disease Mortality: A Cohort Study

CONTEXT

Cushing's disease (CD) is a life-threating disease, with increased mortality in comparison with the general population.

OBJECTIVE

This study aimed to evaluate standardized mortality ratios (SMRs) in CD patients. We also analyzed independent risk factors related to increased mortality.

DESIGN

We conducted a longitudinal cohort study in a 3rd level specialty center, from 1979 to 2018, in patients with CD.

RESULTS

From 1375 cases with a pathology diagnosis of pituitary adenoma, 191 cases had the confirmed diagnosis of CD (14%). A total of 172 patients completed follow-up, with a mean age at diagnosis of 33 ± 11 years, female predominance (n = 154, 89.5%), majority of them with microadenoma (n = 136, 79%), and a median follow-up of 7.5 years (2.4-15). Eighteen patients (10.5%) died, 8 of them (44%) were with active CD, 8 (44%) were under remission, and 2 (11%) were under disease control. Estimated all-cause SMR = 3.1, 95% confidence interval (CI) 1.9-4.8, P < 0.001. Cardiovascular disease was the main cause of death (SMR = 4.2, 1.5-9.3, P = 0.01). Multivariate Cox regression models adjusted for potential cofounders showed that diabetes (HR = 5.2, IC 95% 1.8-15.4, P = 0.002), high cortisol levels after 1600 hours at diagnosis (3.4, 2.3-7.0, P = 0.02), and active CD (7.5, 3.8-17.3, P = 0.003) significantly increased the risk of mortality.

CONCLUSIONS

Main cause of CD mortality was cardiovascular disease. Main risk factors for mortality were uncontrolled diabetes, persistently high cortisol levels after 1600 hours at diagnosis, and active disease at last follow-up.

Outcomes of pituitary surgery for Cushing's disease: a systematic review and meta-analysis

PURPOSE

Transsphenoidal surgery (TSS) is the first-line treatment for Cushing's disease (CD). This review aimed to synthesize the remission and recurrence rates following TSS for CD and identify predictors of these outcomes.

METHODS

Medline (1946-) and Embase (1947-) were searched until 23rd January 2019 for original studies. A meta-analysis was performed of remission and recurrence rates. Studies were excluded if patients had prior radiosurgery/radiotherapy, mixed pathologies or interventions without separated data, follow-up not reported or population size < 20. For recurrence rate syntheses, studies with follow-up < 6 months were excluded.

RESULTS

The search produced 2663 studies, of which n = 68 were included, involving 5664 patients. Remission rates after primary and revision TSS were 80% [77-82] and 58% [50-66] at last follow-up. After primary TSS, predictors of remission were micro- v macroadenomas (83% v 68%, p < 0.01), imaging-visible adenomas (81% v 69%, p < 0.01), adenomas confirmed on histopathology (87% v 45%, p < 0.01), absence of cavernous sinus invasion (80% v 30%, p < 0.01), postoperative serum cortisol (MSeC) nadir < 2 μg/dL (< 55 nmol/L; 95% v 46%, p < 0.01) and lower preoperative 24-h urine free cortisol (1250 nmol v 1726 nmol, p < 0.01). For revision TSS, predictors of remission were postoperative MSeC nadir < 2 μg/dL (< 55 nmol/L; 100% v 38%, p < 0.01) and operations for recurrence v persistence (80% v 54%, p < 0.01). Recurrence rates after primary and revision TSS were 18% [14-22] and 28% [16-42].

CONCLUSIONS

TSS is most effective in primary microadenomas, visible on preoperative imaging and without CS invasion, lower preoperative 24-h urine free cortisol and postoperative MSeC nadir < 2 μg/dL (< 55 nmol/L).

ACTH increment post total bilateral adrenalectomy for Cushing's disease: a consistent biosignature for predicting Nelson's syndrome

PURPOSE

Nelson's syndrome (NS) is regarded as an aggressive complication of total bilateral adrenalectomy (TBA) for Cushing's disease (CD). This challenge may be addressed by using clinical criteria to guide frequency of neuroimaging to enable timely management of NS and also avoid unnecessary frequent imaging.

METHODS

All patients (n = 43) with CD subjected to TBA over 35 years at a tertiary care centre were included. NS was defined as a newly appearing or expanding (> 2 mm) pituitary adenoma with or without ACTH levels exceeding 500 pg/ml. Pre-and post-TBA parameters like clinical symptomatology, cortisol, ACTH and radiology were analysed for the prediction of NS.

RESULTS

NS developed in 39.5% (n = 17) patients with a median follow-up of 7 years. Half of them had new appearance, while rest had an expansion of pre-existing pituitary tumour. Majority (90%) had ACTH above 500 pg/ml. On Cox proportional hazards analysis, frequent discriminatory features of protein catabolism (≥ 4) (HR 1.15, CI 0.18, 7.06), proximal myopathy (HR 8.82, CI 1.12, 69.58) and annual ACTH increment of 113 pg/ml (HR 12.56, CI 1.88, 88.76) predicted NS. First post-operative year ACTH indices predicting NS included ACTH rise of 116 pg/ml and absolute ACTH of 142 pg/ml (sensitivity, specificity exceeding 90%). Annual ACTH increment exceeding 113 pg/ml, ≥ 4 discriminatory features and uncontrolled hypertension had the best overall prediction.

CONCLUSION

Patients who developed NS had higher rebound rise of ACTH following TBA and a more severe disease phenotype at baseline. Consistent ACTH increment can be used as a marker for predicting the development of NS.

Management of patients with persistent or recurrent Cushing's disease after initial pituitary surgery

INTRODUCTION

Treatment options for persistent and recurrent Cushing's disease (CD) include an individualized approach for repeat surgery, medical treatment, radiation therapy (RT), and bilateral adrenalectomy (BLA).

AREAS COVERED

In this expert opinion perspective, the authors review the latest treatment(s) for persistent/recurrent CD. A PubMed search was undertaken (English articles through May 2020) and relevant articles discussed. Repeat pituitary surgery should be considered in most patients with proven hypercortisolism; there is potential for cure with low risk of major complications. Medical therapy is valuable either alone, while awaiting the effects of RT, or in preparation for BLA. Medical therapy includes steroidogenesis inhibitors, agents that act at the pituitary or glucocorticoid receptor level, and novel agents in development. Radiation therapy has been used successfully to treat CD, but hypopituitarism risk and delayed efficacy (improved with radiosurgery) are major drawbacks. Laparoscopic BLA is safe and effective in patients with severe, difficult-to-manage hypercortisolism, but long-term follow-up is required as corticotroph tumor progression can develop.

EXPERT OPINION

Treatment of persistent/recurrent CD is challenging. Most patients require >1 therapy to achieve long-lasting remission. There is currently no ideal single treatment option that provides high and rapid efficacy, low adverse effects, and preserves normal pituitary-adrenal axis function.

Nelson's Syndrome: An Update

Nelson's syndrome (NS) is a condition which may develop in patients with Cushing's disease after bilateral adrenalectomy. Although there is no formal consensus on what defines NS, corticotroph tumor growth and/or gradually increasing ACTH levels are important diagnostic elements. Pathogenesis is unclear and well-established predictive factors are lacking; high ACTH during the first year after bilateral adrenalectomy is the most consistently reported predictive parameter. Management is individualized and includes surgery, with or without radiotherapy, radiotherapy alone, and observation; medical treatments have shown inconsistent results. A subset of tumors demonstrates aggressive behavior with challenging management, malignant transformation and poor prognosis.

Outcomes of Patients with Nelson's Syndrome after Primary Treatment: A Multicenter Study from 13 UK Pituitary Centers

CONTEXT

Long-term outcomes of patients with Nelson's syndrome (NS) have been poorly explored, especially in the modern era.

OBJECTIVE

To elucidate tumor control rates, effectiveness of various treatments, and markers of prognostic relevance in patients with NS.

PATIENTS, DESIGN, AND SETTING

Retrospective cohort study of 68 patients from 13 UK pituitary centers with median imaging follow-up of 13 years (range 1-45) since NS diagnosis.

RESULTS

Management of Cushing's disease (CD) prior to NS diagnosis included surgery+adrenalectomy (n = 30; eight patients had 2 and one had 3 pituitary operations), surgery+radiotherapy+adrenalectomy (n = 17; two received >1 courses of irradiation, two had ≥2 pituitary surgeries), radiotherapy+adrenalectomy (n = 2), and adrenalectomy (n = 19). Primary management of NS mainly included surgery, radiotherapy, surgery+radiotherapy, and observation; 10-year tumor progression-free survival was 62% (surgery 80%, radiotherapy 52%, surgery+radiotherapy 81%, observation 51%). Sex, age at CD or NS diagnosis, size of adenoma (micro-/macroadenoma) at CD diagnosis, presence of pituitary tumor on imaging prior adrenalectomy, and mode of NS primary management were not predictors of tumor progression. Mode of management of CD before NS diagnosis was a significant factor predicting progression, with the group treated by surgery+radiotherapy+adrenalectomy for their CD showing the highest risk (hazard ratio 4.6; 95% confidence interval, 1.6-13.5). During follow-up, 3% of patients had malignant transformation with spinal metastases and 4% died of aggressively enlarging tumor.

CONCLUSIONS

At 10 years follow-up, 38% of the patients diagnosed with NS showed progression of their corticotroph tumor. Complexity of treatments for the CD prior to NS diagnosis, possibly reflecting corticotroph adenoma aggressiveness, predicts long-term tumor prognosis.

Therapeutic options after surgical failure in Cushing's disease: A critical review

Cushing's disease (CD) is the most common etiology of Cushing's syndrome (CD) due to corticotroph pituitary adenoma, which are in most cases small (80-90% microadenomas) and in about 40% cannot be visualized on imaging of the sella. First-line treatment for CD is transsphenoidal surgery (TSS) with the aim of complete adenoma removal and preservation of pituitary gland function. As complete adenoma resection is not always possible, surgical failure is a common problem. This can be the case either due to persistent hypercortisolism after first TSS or recurrence of hypercortisolism after initially achieving remission. For these scenarios exist several therapeutic options with their inherent characteristics, which will be covered by this review.

The Treatment of Refractory Pituitary Adenomas

Refractory pituitary adenomas (PAs) are defined as aggressive-invasive PAs characterized by a high Ki-67 index, rapid growth, frequent recurrence, and resistance to conventional treatments. It is notoriously difficult to manage refractory PAs because the efficacy of current therapeutic options is limited. The purpose of this review is to address currently employed and promising therapeutic strategies for the treatment of refractory PAs. Except for prolactinomas, neurosurgery is the first-line option, but most refractory PAs often recur or re-grow after initial surgery and require further treatments. Medical therapy, radiotherapy and re-operation are explored when surgery has failed to completely resect tumors; however, refractory PAs are usually resistant to these treatments. As a salvage treatment, temozolomide (TMZ) has shown promising results and is currently used for all types of refractory PAs. However, not all refractory PAs are responsive to TMZ treatment, and some of these PAs are resistant to TMZ. Although targeted therapies such as vascular endothelial growth factor, epidermal growth factor and mTOR inhibitors have also been used to treat refractory PAs, the effectiveness of these targeted therapies is still not known due to a lack of data from randomized prospective trials. As a novel therapeutic method, cancer immunotherapy is a promising strategy for the treatment of refractory PAs, but further preclinical research and clinical trials are needed to assess the efficacy of this new approach. In summary, early identification and a multidisciplinary approach are required to treat refractory PAs.

Effect of cabergoline monotherapy in Cushing's disease: an individual participant data meta-analysis

CONTEXT

The primary treatment of choice for Cushing's disease (CD) is the removal of the pituitary adenoma by transsphenoidal surgery (TSS). The surgical failure is seen in up to 75% of cases depending on the experience of the surgeon in different studies. Medical therapy is one of the options for the treatment of recurrent or persistent CD.

METHODOLOGY

The primary outcome of this meta-analysis was to find the proportion of patients achieving normalisation of 24-h urinary free cortisol (remission of CD) following cabergoline monotherapy. Literature search was conducted in January 2018 in PubMed/MEDLINE database from its date of inception to 31st December 2017. The search strategy used was "[(cushing) OR Cushing's] AND cabergoline". Individual participant data were extracted from the included studies and risk of bias was analysed by review checklist proposed by MOOSE.

RESULTS

The individual participant data of 124 patients from six observational studies were included in this meta-analysis. 92 patients (74.2%) had past pituitary surgery. The proportion of patients achieving remission of Cushing’s disease (CD) with cabergoline monotherapy was 34% (95% confidence interval 0.26–0.43; P = 0.001) [corrected]. The previous surgery [odds ratio (OR) 28.4], duration of cabergoline monotherapy (OR 1.31) and maximum cabergoline dose (OR 0.19) were predictors for remission of CD. Mild and severe side effects were reported in 37.3% and 5.6% of patients, respectively, during cabergoline monotherapy.

CONCLUSIONS

This meta-analysis shows that cabergoline monotherapy is a reasonable alternative for subjects with persistent or recurrent CD after TSS. It can also be used in CD patients either as a bridge therapy while waiting for surgery or in those unwilling for surgery or have contraindication to it.

Cryptococcal meningitis after transnasal transsphenoidal pituitary microsurgery of ACTH-secreting pituitary adenoma: A case report

RATIONALE

Microbial infection should be regarded in the differential diagnosis of neurosurgical complications after transnasal transsphenoidal pituitary microsurgery, albeit cryptococcal meningitis is rare. This article will discuss the risk factors of cryptococcal meningitis in patients underwent transnasal transsphenoidal pituitary microsurgery, and summary the potential origins of infection.

PATIENT CONCERNS AND DIAGNOSIS

Here, we report a case of 37-year-old male who had cryptococcal meningitis after transnasal transsphenoidal pituitary microsurgery of a relapsing ACTH-secreting pituitary adenoma.

INTERVENTION

Standard therapy for Cryptococcus neoformans (fluconazole [400 mg per day] and flucytosine) was administered and followed by maintenance dose.

OUTCOMES

The patient had been on treatment for one and a half years during follow-up and reported neurologically well with repeated negative cerebrospinal fluid (CSF) culture until sudden death of heart arrest.

MAIN LESSONS TO LEARN

C neoformans can be a possible cause of meningitis in immunocompetent patients after transnasal transsphenoidal pituitary microsurgery. Risk factors, such as pre-existed pulmonary infection and Cushing-associated hypercortisolemia, should be stressed. Promising preventive measures may include preoperative routine sputum smear and India-ink stain for screening, preoperative treatment of cryptococcal pneumonia, postoperative antibiotic management, and a more secure skull base reconstruction. Radiation and pharmaceutical treatment may be alternative for recurrent Cushing disease.