Outcome of Transsphenoidal Surgery for Cushing Disease: A Single-Center Experience Over 32 Years

Predictors of Durable Remission After Successful Surgery for Cushing Disease: Results From the Multicenter RAPID Registry

BACKGROUND AND OBJECTIVE

Cushing disease (CD) affects mortality and quality of life along with limited long-term remission, underscoring the need to better identify recurrence risk. The identification of surgical or imaging predictors for CD remission after transsphenoidal surgery has yielded some inconsistent results and has been limited by single-center, single-surgeon, or meta-analyses studies. We sought to evaluate the multicenter Registry of Adenomas of the Pituitary and Related Disorders (RAPID) database of academic US pituitary centers to assess whether robust nonhormonal recurrence predictors could be elucidated.

METHODS

Patients with treated CD from 2011 to 2023 were included. The perioperative and long-term characteristics of CD patients with and without recurrence were assessed using univariable and multivariable analyses.

RESULTS

Of 383 patients with CD from 26 surgeons achieving postoperative remission, 288 (75.2%) maintained remission at last follow-up while 95 (24.8%) showed recurrence (median time to recurrence 9.99 ± 1.34 years). Patients with recurrence required longer postoperative hospital stays (5 ± 3 vs 4 ± 2 days, P = .002), had larger average tumor volumes (1.76 ± 2.53 cm3 vs 0.49 ± 1.17 cm3, P = .0001), and more often previously failed prior treatment (31.1% vs 14.9%, P = .001) mostly being prior surgery. Multivariable hazard prediction models for tumor recurrence found younger age (odds ratio [OR] = 0.95, P = .002) and Knosp grade of 0 (OR = 0.09, reference Knosp grade 4, P = .03) to be protective against recurrence. Comparison of Knosp grade 0 to 2 vs 3 to 4 showed that lower grades had reduced risk of recurrence (OR = 0.27, P = .04). Other factors such as length of stay, surgeon experience, prior tumor treatment, and Knosp grades 1, 2, or 3 failed to reach levels of statistical significance in multivariable analysis.

CONCLUSION

This multicenter study centers suggests that the strongest predictors of recurrence include tumor size/invasion and age. This insight can help with patient counseling and prognostication. Long-term follow-up is necessary for patients, and early treatment of small tumors may improve outcomes.

Interpetrosal sphingosine-1-phosphate ratio predicting Cushing's disease tumor laterality and remission after surgery

Background

Cushing's disease (CD) poses significant challenges in its treatment due to the lack of reliable biomarkers for predicting tumor localization or postoperative clinical outcomes. Sphingosine-1-phosphate (S1P) has been shown to increase cortisol biosynthesis and is regulated by adrenocorticotropic hormone (ACTH).

Methods

We employed bilateral inferior petrosal sinus sampling (BIPSS), which is considered the gold standard for diagnosing pituitary sources of CD, to obtain blood samples and explore the clinical predictive value of the S1P concentration ratio in determining tumor laterality and postoperative remission. We evaluated 50 samples from 25 patients who underwent BIPSS to measure S1P levels in the inferior petrosal sinuses bilaterally.

Results

Serum S1P levels in patients with CD were significantly higher on the adenoma side of the inferior petrosal sinus than on the nonadenoma side (397.7 ± 15.4 vs. 261.9 ± 14.88; P < 0.05). The accuracy of diagnosing tumor laterality with the interpetrosal S1P and ACTH ratios and the combination of the two was 64%, 56% and 73%, respectively. The receiver operating characteristic curve analysis revealed that the combination of interpetrosal S1P and ACTH ratios, as a predictor of tumor laterality, exhibited a sensitivity of 81.82% and a specificity of 75%, with an area under the curve value of 84.09%. Moreover, we observed that a high interpetrosal S1P ratio was associated with nonremission after surgery. Correlation analyses demonstrated that the interpetrosal S1P ratio was associated with preoperative follicle-stimulating hormone (FSH), luteinizing hormone (LH), and postoperative ACTH 8 am levels (P < 0.05).

Conclusion

Our study demonstrated a significant association between the interpetrosal S1P ratio and tumor laterality, as well as postoperative remission in CD, suggesting that the interpetrosal S1P ratio could serve as a valuable biomarker in clinical practice.

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.

Generating novel pituitary datasets from open-source imaging data and deep volumetric segmentation

PURPOSE

The estimated incidence of pituitary adenomas in the general population is 10-30%, yet radiographic diagnosis remains a challenge. Diagnosis is complicated by the heterogeneity of radiographic features in both normal (e.g. complex anatomy, pregnancy) and pathologic states (e.g. primary endocrinopathy, hypophysitis). Clinical symptoms and laboratory testing are often equivocal, which can result in misdiagnosis or unnecessary specialist referrals. Computer vision models can aid in pituitary adenoma diagnosis; however, a major challenge to model development is the lack of dedicated pituitary imaging datasets. We hypothesized that deep volumetric segmentation models trained to extract the sellar and parasellar region from existing whole-brain MRI scans could be used to generate a novel dataset of pituitary imaging.

METHODS

Six open-source whole-brain MRI datasets, created for research purposes, were included for model development. Deep learning-based volumetric segmentation models were trained using 318 manually annotated MRI scans from a single open-source MRI dataset. Out-of-distribution volumetric segmentation performance was then tested on 418 MRIs from five held-out research datasets.

RESULTS

On our annotated images, agreement between manual and model volumetric segmentations was high. Dice scores (a measure of overlap) ranged 0.76-0.82 for both in-distribution and out-of-distribution model testing. In total, 6,755 MRIs from six data sources were included in the final generated pituitary dataset.

CONCLUSIONS

We present the first and largest dataset of pituitary imaging constructed using existing MRI data and deep volumetric segmentation models trained to identify sellar and parasellar anatomy. The model generalizes well across patient populations and MRI scanner types. We hope our pituitary dataset will be an integral part of future machine learning research on pituitary pathologies.

The importance of MRI quality and reader's experience for detecting an adenoma in Cushing's disease

OBJECTIVE

In Cushing's disease (CD), detection of an adenoma by MRI is challenging. The aim of this study is to compare real-life MRI in the initial diagnostic workup of CD with high-quality MRI performed in a tertiary center for pituitary diseases.

DESIGN AND METHODS

We retrospectively analyzed 139 patients with CD who underwent primary transsphenoidal surgery (TSS) in our department and had both an MRI conducted at a different institution (external MRI; extMRI) and an MRI conducted at our institution (internal MRI; intMRI). Preoperative interpretation of MRI was performed independently by an external radiologist (extRAD), an internal neuroradiologist (intRAD) and a pituitary surgeon (SURG). Intraoperative detection of an adenoma and endocrinological remission provided proof of the true adenoma localization in 105 patients.

RESULTS

Interpretation of extMRI by extRAD and SURG was concordant in only 64% (89/139) of cases, while 74.1% (103/139) concordance was observed for interpretation of intMRI by intRAD and SURG. Based on extMRI, the true localization of the adenoma was correctly predicted in only 46.7% of the patients by extRAD and in 65.7% by SURG. In contrast, the sensitivity to correctly identify the adenoma on intMRI was 80.0% for intRAD and 94.3% for SURG.

CONCLUSION

Both the quality of MRI and the reader's experience are paramount for detection of microadenomas in CD. Every effort should be made to perform high-quality initial MRI according to current standards and to ensure rating by an expert in pituitary imaging.

Surgery and perioperative management of patients with Cushing's disease

Transsphenoidal surgery (TSS) is the initial treatment modality of first choice in Cushing's disease (CD). With microscopic TSS and endoscopic TSS, two operative techniques with equally favourable remission rates and operative morbidity are available. On average, remission is achieved with primary TSS in 80% of patients with microadenomas and 60% of patients with macroadenomas. The current literature indicates that remission rates in repeat TSS for microadenomas can also exceed 70%. Experience with TSS in CD plays an important role in the success rate and centralization in Pituitary Centres of Excellence has been proposed. Microadenoma stage, imaging-visible adenoma, confirmation of ACTH-positive adenoma on histopathology and noninvasiveness are positive predictors for postoperative remission. In postoperative management, a steroid-sparing protocol with early postoperative assessment of remission status is recommended. Convincing evidence suggests that prolonged postoperative prophylactic antithrombotic measures can significantly reduce the risk of postoperative thromboembolic events in CD. Prevention or successful treatment of cortisol withdrawal syndrome remains an unsolved issue that should be a focus of future research. The further development and broad availability of functional imaging hold promise for improved preoperative detection of microadenomas. Intraoperative identification of microadenomas by specific fluorescent targeting could be a promising future avenue for the treatment of patients with negative imaging.

Long-term follow-up and predictors of recurrence of Cushing's disease

Transsphenoidal surgery is the first-line treatment for Cushing's disease to selectively remove the tumor. The rate of postoperative remission is estimated around 70%-80% in expert centers. However, the long-term remission rate is lower because of recurrence during follow-up that can be observed in 15% to 25% of the patients depending on the studies and duration of follow-up. There is no significant predictive factor of recurrence before surgery, but postoperative corticotroph insufficiency and its duration has been found to be a protective factor for recurrence in many studies. The persistence of a positive response to desmopressin after surgery is associated with a higher rate of recurrence. Long term monitoring for recurrence with annual clinical and hormonal investigations after the hypothalamic-pituitary-adrenal axis postoperative recovery is advised. The biological tests used for the diagnosis of Cushing's syndrome (24 h-urinary-free cortisol [UFC], late-night salivary or serum cortisol, 1 mg dexamethasone suppression test) can be used to screen for recurrence. Several studies report that increased late night cortisol and alterations of dynamic testing can be observed before the increased 24 h-UFC. For this reason it is suggested that late-night salivary cortisol would be a very sensitive tool to diagnose recurrence, pending the realization of several assays in case of borderline or discrepant result. This review will summarize the knowledge about recurrence of Cushing's disease after pituitary surgery and the current recommendations for its monitoring and diagnosis.

Integrative Clinical, Radiological, and Molecular Analysis for Predicting Remission and Recurrence of Cushing Disease

CONTEXT

Adrenocorticotropin (ACTH)-secreting pituitary tumors (ACTHomas) are associated with severe comorbidities and increased mortality. Current treatments mainly focus on remission and prevention of persistent disease and recurrence. However, there are still no useful biomarkers to accurately predict the clinical outcome after surgery, long-term remission, or disease relapse.

OBJECTIVES

This work aimed to identify clinical, biochemical, and molecular markers for predicting long-term clinical outcome and remission in ACTHomas.

METHODS

A retrospective multicenter study was performed with 60 ACTHomas patients diagnosed between 2004 and 2018 with at least 2 years' follow-up. Clinical/biochemical variables were evaluated yearly. Molecular expression profile of the somatostatin/ghrelin/dopamine regulatory systems components and of key pituitary factors and proliferation markers were evaluated in tumor samples after the first surgery.

RESULTS

Clinical variables including tumor size, time until diagnosis/first surgery, serum prolactin, and postsurgery cortisol levels were associated with tumor remission and relapsed disease. The molecular markers analyzed were distinctly expressed in ACTHomas, with some components (ie, SSTR1, CRHR1, and MKI67) showing instructive associations with recurrence and/or remission. Notably, an integrative model including selected clinical variables (tumor size/postsurgery serum cortisol), and molecular markers (SSTR1/CRHR1) can accurately predict the clinical evolution and remission of patients with ACTHomas, generating a receiver operating characteristic curve with an area under the curve of 1 (P < .001).

CONCLUSION

This study demonstrates that the combination of a set of clinical and molecular biomarkers in ACTHomas is able to accurately predict the clinical evolution and remission of patients. Consequently, the postsurgery molecular profile represents a valuable tool for clinical evaluation and follow-up of patients with ACTHomas.

MRI-Negative Cushing's Disease: A Review on Therapeutic Management

OBJECTIVES

In this systematic review and meta-analysis, we review the literature regarding patients with Cushing's disease (CD) with negative or inconclusive magnetic resonance imaging (MRI).

METHODS

A quantitative systematic review was performed. Article selection was performed by searching MEDLINE (using PubMed), EMBASE, and Cochrane electronic bibliographic databases.

RESULTS

28 articles described surgical management of inconclusive MRI or MRI-negative CD. A total of 858 patients underwent surgery for their Cushing adenoma. Different types of surgery, including endoscopic endonasal transsphenoidal surgery (EETS) (190 cases) and microscopic endonasal transsphenoidal surgery (METS) (488 cases), were performed on patients with MRI-negative CD. 7 studies, which included 164 patients, did not describe any surgery. EETS and METS are conducted to achieve selective adenomectomy (231 cases), partial adenomectomy (80 cases), total adenomectomy (13 cases), hemihypophysectomy (15 cases), or enlarged adenomectomy (48 cases). Based on available data on these studies, the remission rate, persistence rate, and recurrence rate after different types of surgeries on patients with MRI-negative CD were 72.97%, 27.03%, and 12.05%, respectively. There was no statistically significant difference between EETS and METS in the subanalysis regarding recurrence rate, remission rate, and persistence rate. However, the recurrence rate in the METS group is almost 3 times higher than in the EETS group.

CONCLUSIONS

Surgery has a good prognosis in patients with MRI-negative CD in terms of remission, and EETS has a lower rate of disease recurrence than METS; therefore, EETS seems to be the potential recommended treatment technique, while to confirm the therapeutic method of choice, further investigations should be done.

Consensus statement by the French Society of Endocrinology (SFE) and French Society of Pediatric Endocrinology & Diabetology (SFEDP) on diagnosis of Cushing's syndrome

Cushing's syndrome is defined by prolonged exposure to glucocorticoids, leading to excess morbidity and mortality. Diagnosis of this rare pathology is difficult due to the low specificity of the clinical signs, the variable severity of the clinical presentation, and the difficulties of interpretation associated with the diagnostic methods. The present consensus paper by 38 experts of the French Society of Endocrinology and the French Society of Pediatric Endocrinology and Diabetology aimed firstly to detail the circumstances suggesting diagnosis and the biologic diagnosis tools and their interpretation for positive diagnosis and for etiologic diagnosis according to ACTH-independent and -dependent mechanisms. Secondly, situations making diagnosis complex (pregnancy, intense hypercortisolism, fluctuating Cushing's syndrome, pediatric forms and genetically determined forms) were detailed. Lastly, methods of surveillance and diagnosis of recurrence were dealt with in the final section.

Diagnostic Pitfalls in Cushing Disease: Surgical Remission Rates, Test Thresholds, and Lessons Learned in 105 Patients

CONTEXT

Confirming a diagnosis of Cushing disease (CD) remains challenging, yet is critically important before recommending transsphenoidal surgery for adenoma resection.

OBJECTIVE

To describe predictive performance of preoperative biochemical and imaging data relative to post-operative remission and clinical characteristics in patients with presumed CD.

DESIGN, SETTING, PATIENTS, INTERVENTIONS

Patients (n = 105; 86% female) who underwent surgery from 2007 through 2020 were classified into 3 groups: group A (n = 84) pathology-proven ACTH adenoma; group B (n = 6) pathology-unproven but with postoperative hypocortisolemia consistent with CD; and group C (n = 15) pathology-unproven, without postoperative hypocortisolemia. Group A + B were combined as confirmed CD and group C as unconfirmed CD.

MAIN OUTCOMES

Group A + B was compared with group C regarding predictive performance of preoperative 24-hour urinary free cortisol (UFC), late night salivary cortisol (LNSC), 1-mg dexamethasone suppression test (DST), plasma ACTH, and pituitary magnetic resonance imaging (MRI).

RESULTS

All groups had a similar clinical phenotype. Compared with group C, group A + B had higher mean UFC (P < 0.001), LNSC (P = 0.003), DST (P = 0.06), and ACTH (P = 0.03) and larger MRI-defined lesions (P < 0.001). The highest accuracy thresholds were: UFC 72 µg/24 hours; LNSC 0.122 µg/dL, DST 2.70 µg/dL, and ACTH 39.1 pg/mL. Early (3-month) biochemical remission was achieved in 76/105 (72%) patients: 76/90(84%) and 0/15(0%) of group A + B vs group C, respectively, P < 0.0001. In group A + B, nonremission was strongly associated with adenoma cavernous sinus invasion.

CONCLUSIONS

Use of strict biochemical thresholds may help avoid offering transsphenoidal surgery to presumed CD patients with equivocal data and improve surgical remission rates. Patients with Cushingoid phenotype but equivocal biochemical data warrant additional rigorous testing.

The clinical outcomes of imaging modalities for surgical management Cushing's disease - A systematic review and meta-analysis

INTRODUCTION

Cushing's disease presents major diagnostic and management challenges. Although numerous preoperative and intraoperative imaging modalities have been deployed, it is unclear whether these investigations have improved surgical outcomes. Our objective was to investigate whether advances in imaging improved outcomes for Cushing's disease.

METHODS

Searches of PubMed and EMBASE were conducted. Studies reporting on imaging modalities and clinical outcomes after surgical management of Cushing's disease were included. Multilevel multivariable meta-regressions identified predictors of outcomes, adjusting for confounders and heterogeneity prior to investigating the effects of imaging.

RESULTS

166 non-controlled single-arm studies were included, comprising 13181 patients over 44 years.The overall remission rate was 77.0% [CI: 74.9%-79.0%]. Cavernous sinus invasion (OR: 0.21 [CI: 0.07-0.66]; p=0.010), radiologically undetectable lesions (OR: 0.50 [CI: 0.37-0.69]; p<0.0001), previous surgery (OR=0.48 [CI: 0.28-0.81]; p=0.008), and lesions ≥10mm (OR: 0.63 [CI: 0.35-1.14]; p=0.12) were associated with lower remission. Less stringent thresholds for remission was associated with higher reported remission (OR: 1.37 [CI: 1.1-1.72]; p=0.007). After adjusting for this heterogeneity, no imaging modality showed significant differences in remission compared to standard preoperative MRI.The overall recurrence rate was 14.5% [CI: 12.1%-17.1%]. Lesion ≥10mm was associated with greater recurrence (OR: 1.83 [CI: 1.13-2.96]; p=0.015), as was greater duration of follow-up (OR: 1.53 (CI: 1.17-2.01); p=0.002). No imaging modality was associated with significant differences in recurrence.Despite significant improvements in detection rates over four decades, there were no significant changes in the reported remission or recurrence rates.

CONCLUSION

A lack of controlled comparative studies makes it difficult to draw definitive conclusions. Within this limitation, the results suggest that despite improvements in radiological detection rates of Cushing's disease over the last four decades, there were no changes in clinical outcomes. Advances in imaging alone may be insufficient to improve surgical outcomes.

SYSTEMATIC REVIEW REGISTRATION

https://www.crd.york.ac.uk/PROSPERO/, identifier CRD42020187751.

Surgical outcome of transsphenoidal surgery in Cushing's disease: a case series of 1106 patients from a single center over 30 years

OBJECTIVE

Transsphenoidal surgery (TSS) is the first-line treatment for patients with Cushing's disease (CD). However, the reported remission rates of patients who received TSS vary widely between different studies, and the predictors of surgical outcomes remain controversial. The present study analyzed the early outcome of TSS in a large population of patients with CD at a single center, and identified potential predictors of initial remission of TSS in patients with CD.

METHODS

The clinical features and surgical outcomes of CD patients who underwent TSS between 1988 and 2018 at Peking Union Medical College Hospital (PUMCH) were collected and analyzed from their medical records.

RESULTS

Of the 1604 CD patients who underwent TSS at PUMCH between February 1988 and October 2018, 1106 patients had complete medical data and pathological results. After surgery, the overall postoperative initial remission rate was 72.5, and 27.5% of patients maintained persistent hypercortisolism. The initial remission rate of patients with preoperative noninvasive adenoma based on MRI (77.1%), intraoperative noninvasiveness (72.5%), microadenoma (74.3%), pathological confirmation (76.4%), and first TSS (73.9%) was significantly higher than that in patients with preoperative invasive adenoma (53.0%), intraoperative invasiveness (60.7%), macroadenomas (65.9%), pathologically negative (49.7%), and repeat TSS (56.0%), respectively (all P < 0.05). The initial remission rate in patients with pseudocapsule-based extracapsular resection (88.1%), MRI-visible adenoma (74.2%) was higher than that in patients without pseudocapsule-based extracapsular resection (77.1%), and with MRI-negative results (64.5%), respectively, but did not reach statistical significance (All P > 0.05). Striking, there was no significant differences in initial remission rates between patients who underwent selective adenomectomy and enlarged adenomectomy (P > 0.05). Whereas, the initial remission rates in patients who underwent partial hypophysectomy only was 51.0%, which was much lower than that in patients underwent selective adenomectomy and enlarged adenomectomy (P < 0.05).

CONCLUSION

The TSS is a safe and effective procedure for the treatment of CD. Whereas, preoperative invasiveness based on MRI, intraoperative invasiveness, macroadenomas pathologically negative, and repeat TSS are related to lower initial remission rates.

Electronic Medical Records as Input to Predict Postoperative Immediate Remission of Cushing's Disease: Application of Word Embedding

Background

No existing machine learning (ML)-based models use free text from electronic medical records (EMR) as input to predict immediate remission (IR) of Cushing’s disease (CD) after transsphenoidal surgery.

Purpose

The aim of the present study is to develop an ML-based model that uses EMR that include both structured features and free text as input to preoperatively predict IR after transsphenoidal surgery.

Methods

A total of 419 patients with CD from Peking Union Medical College Hospital were enrolled between January 2014 and August 2020. The EMR of the patients were embedded and transformed into low-dimensional dense vectors that can be included in four ML-based models together with structured features. The area under the curve (AUC) of receiver operating characteristic curves was used to evaluate the performance of the models.

Results

The overall remission rate of the 419 patients was 75.7%. From the results of logistic multivariate analysis, operation (p < 0.001), invasion of cavernous sinus from MRI (p = 0.046), and ACTH (p = 0.024) were strongly correlated with IR. The AUC values for the four ML-based models ranged from 0.686 to 0.793. The highest AUC value (0.793) was for logistic regression when 11 structured features and “individual conclusions of the case by doctor” were included.

Conclusion

An ML-based model was developed using both structured and unstructured features (after being processed using a word embedding method) as input to preoperatively predict postoperative IR.

Pituitary surgery for Cushing's disease

BACKGROUND

Surgery is currently the first-line treatment of Cushing's disease. Surgery for Cushing's patients requires technical specificity, especially if no adenoma is identified on dedicated preoperative pituitary MRI.

METHOD

From 2006 to 2020, 683 patients with Cushing's disease were operated on with a mononostril endoscopic endonasal approach by the same two senior neurosurgeons. Here, we report the particularities of this challenging surgery.

CONCLUSION

A rigorous and planned surgical strategy avoids the pitfalls of Cushing's disease surgery and leads to a high rate of endocrine remission.

[Modern aspects of surgery for cushing's disease]

Cushing's disease is a severe neuroendocrine disorder caused by chronic hypersecretion of ACTH by pituitary adenoma (corticotropinoma). Surgical resection is a gold standard for this disease resulting stable remission in about 65-95% of cases. Despite benign nature of corticotropinoma, recurrence rate is still higher (25-35%) even in specialized neurosurgical centers. Modifications in surgical strategy can prolong recurrence-free period.

Machine learning-based prediction of outcomes of the endoscopic endonasal approach in Cushing disease: is the future coming?

OBJECTIVE

Machine learning (ML) is an innovative method to analyze large and complex data sets. The aim of this study was to evaluate the use of ML to identify predictors of early postsurgical and long-term outcomes in patients treated for Cushing disease (CD).

METHODS

All consecutive patients in our center who underwent surgery for CD through the endoscopic endonasal approach were retrospectively reviewed. Study endpoints were gross-tumor removal (GTR), postsurgical remission, and long-term control of disease. Several demographic, radiological, and histological factors were assessed as potential predictors. For ML-based modeling, data were randomly divided into 2 sets with an 80% to 20% ratio for bootstrapped training and testing, respectively. Several algorithms were tested and tuned for the area under the curve (AUC).

RESULTS

The study included 151 patients. GTR was achieved in 137 patients (91%), and postsurgical hypersecretion remission was achieved in 133 patients (88%). At last follow-up, 116 patients (77%) were still in remission after surgery and in 21 patients (14%), CD was controlled with complementary treatment (overall, of 131 cases, 87% were under control at follow-up). At internal validation, the endpoints were predicted with AUCs of 0.81-1.00, accuracy of 81%-100%, and Brier scores of 0.035-0.151. Tumor size and invasiveness and histological confirmation of adrenocorticotropic hormone (ACTH)-secreting cells were the main predictors for the 3 endpoints of interest.

CONCLUSIONS

ML algorithms were used to train and internally validate robust models for all the endpoints, giving accurate outcome predictions in CD cases. This analytical method seems promising for potentially improving future patient care and counseling; however, careful clinical interpretation of the results remains necessary before any clinical adoption of ML. Moreover, further studies and increased sample sizes are definitely required before the widespread adoption of ML to the study of CD.

Outcomes of Transsphenoidal Surgery in Cushing Disease Patients with Negative Pituitary Magnetic Resonance Imaging Findings: A Single-Center Experience

OBJECTIVE

Transsphenoidal surgery (TSS) is a first-line treatment for Cushing disease (CD). However, a subset of patients with CD have no visible adenoma on magnetic resonance imaging (MRI), and whether MRI results affect surgical outcomes is controversial. The aim of this study was to compare the surgical outcomes of CD patients with negative MRI findings to those of patients with positive MRI findings.

METHODS

The clinical features and outcomes of CD patients who underwent TSS between January 2000 and July 2019 at Peking Union Medical College Hospital were collected from medical records. The clinical, endocrinologic, histopathologic, surgical outcomes, and a minimum 12-month follow-up of 125 consecutive CD patients with negative MRI findings were compared with those of 1,031 consecutive CD patients with MRI-visible adenomas.

RESULTS

The total remission rate was 73.3% after TSS, and 11.8% of patients experienced recurrence. Of 1,031 patients with MRI-visible adenomas, postoperative remission was achieved in 762 patients (73.9%), and the recurrence of CD was observed in 94 (12.3%) patients. Of the 125 patients with negative MRI findings, postoperative remission was achieved in 85 (68%) patients, and recurrence was observed in 6 (7.1%) patients. The remission rate and recurrence rate were not significantly different between patients with negative MRI findings and those with positive MRI findings (all P>.05). The remission rate was not significantly different between patients who did or did not undergo bilateral inferior petrosal sinus sampling (BIPSS) in patients with negative MRI findings (P>.05). In the patients with negative MRI findings who underwent BIPSS, the remission rate of patients with positive BIPSS results was not different from that in patients with negative BIPSS results (P>.05). The lack of prior TSS, the detection of a tumor during operation, and pathologic confirmation of adenoma were associated with a higher surgical remission rate in patients with negative MRI findings (all P<.05). Similar results were observed in the patients with positive MRI findings (all P<.05). In addition, the major perioperative complications, including intraoperative cerebrospinal fluid leakage, hypopituitarism, and transient diabetes insipidus, were not related to the MRI results (all P>.05).

CONCLUSION

The remission rate and recurrence rate were not different between patients with negative MRI findings and those with positive MRI findings. If CD is clearly diagnosed according to biochemical tests, radiologic examinations, and BIPSS, we recommend TSS as the first-line treatment for patients, even if the MRI results are negative.

Machine Learning in Preoperative Prediction of Postoperative Immediate Remission of Histology-Positive Cushing's Disease

BACKGROUND

There are no established accurate models that use machine learning (ML) methods to preoperatively predict immediate remission after transsphenoidal surgery (TSS) in patients diagnosed with histology-positive Cushing's disease (CD).

PURPOSE

Our current study aims to devise and assess an ML-based model to preoperatively predict immediate remission after TSS in patients with CD.

METHODS

A total of 1,045 participants with CD who received TSS at Peking Union Medical College Hospital in a 20-year period (between February 2000 and September 2019) were enrolled in the present study. In total nine ML classifiers were applied to construct models for the preoperative prediction of immediate remission with preoperative factors. The area under the receiver operating characteristic (ROC) curve (AUC) was used to evaluate the performance of the models. The performance of each ML-based model was evaluated in terms of AUC.

RESULTS

The overall immediate remission rate was 73.3% (766/1045). First operation (p<0.001), cavernous sinus invasion on preoperative MRI(p<0.001), tumour size (p<0.001), preoperative ACTH (p=0.008), and disease duration (p=0.010) were significantly related to immediate remission on logistic univariate analysis. The AUCs of the models ranged between 0.664 and 0.743. The highest AUC, i.e., the best performance, was 0.743, which was achieved by stacking ensemble method with four factors: first operation, cavernous sinus invasion on preoperative MRI, tumour size and preoperative ACTH.

CONCLUSION

We developed a readily available ML-based model for the preoperative prediction of immediate remission in patients with CD.

Predictors of Immediate Remission after Surgery in Cushing's Disease Patients: A Large Retrospective Study from a Single Center

OBJECTIVE

Transsphenoidal surgery (TSS) is the first-line treatment of patients with Cushing's disease (CD). However, biochemical remission rates after TSS for CD vary from 59 to 95%, and the predictors of surgical outcomes remain unclear. The aim of this study was to identify the predictors of early outcomes in patients with CD treated with TSS.

METHODS

The clinical features and outcomes of CD patients who underwent TSS between February 2000 and September 2019 at the Peking Union Medical College Hospital were collected from medical records and analyzed. Uni- and multivariate odds ratio (OR) analyses were performed to identify the predictors of early outcomes in patients with CD.

RESULTS

A total of 1,045 patients were included. The median age at TSS was 34.0 years (IQR 26.0-45.0), with a female:male ratio of 4.2:1 (844/201). The median duration of symptoms was 46.0 months (IQR 24.0-72.0). After surgery, the overall postoperative immediate remission rate was 73.3%, and 26.7% of patients had persistent hypercortisolism. Univariate analysis demonstrated that the number of operations was correlated with a lower immediate remission rate (OR 0.393, 95% CI 0.266-0.580, p = 0.000), as was tumor size (OR 0.462, 95% CI 0.334-0.639, p = 0.000), the duration of disease (OR 0.996, 95% CI 0.993-0.999, p = 0.003), and preoperative ACTH concentration (0.998, 95% CI 0.996-0.999, p = 0.003). Cavernous sinus invasion has also been identified as an important factor associated with a lower immediate remission rate (OR 0.275, 95% CI 0.166-0.456, p = 0.000). No correlations were detected between the immediate outcomes and age, gender, BMI, the combination of a low- and high-dose dexamethasone suppression test, preoperative morning serum cortisol level, or 24-h urinary free cortisol level (all p > 0.05). The results of multivariate analysis were similar to those of univariate analysis. Preoperative ACTH ≤67.35 ng/L predicted remission with 60.9% sensitivity and 49.5% specificity (AUC 0.553; p = 0.008). A cutoff of ≤64.5 months for disease duration predicted immediate remission with 40.5% sensitivity and 71.0% specificity (AUC 0.552; p = 0.01).

CONCLUSION

Early outcomes of TSS in CD patients can be predicted by factors including the number of operations, duration of disease, tumor invasion, tumor size, and preoperative ACTH concentration. These predictors can be used to improve the perioperative management of CD patients.

Recurrence after pituitary surgery in adult Cushing's disease: a systematic review on diagnosis and treatment

PURPOSE

Recurrence after pituitary surgery in Cushing's disease (CD) is a common problem ranging from 5% (minimum) to 50% (maximum) after initially successful surgery, respectively. In this review, we give an overview of the current literature regarding prevalence, diagnosis, and therapeutic options of recurrent CD.

METHODS

We systematically screened the literature regarding recurrent and persistent Cushing's disease using the MESH term Cushing's disease and recurrence. Of 717 results in PubMed, all manuscripts in English and German published between 1980 and April 2020 were screened. Case reports, comments, publications focusing on pediatric CD or CD in veterinary disciplines or studies with very small sample size (patient number < 10) were excluded. Also, papers on CD in pregnancy were not included in this review.

RESULTS AND CONCLUSIONS

Because of the high incidence of recurrence in CD, annual clinical and biochemical follow-up is paramount. 50% of recurrences occur during the first 50 months after first surgery. In case of recurrence, treatment options include second surgery, pituitary radiation, targeted medical therapy to control hypercortisolism, and bilateral adrenalectomy. Success rates of all these treatment options vary between 25 (some of the medical therapy) and 100% (bilateral adrenalectomy). All treatment options have specific advantages, limitations, and side effects. Therefore, treatment decisions have to be individualized according to the specific needs of the patient.

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).

Predicting post-operative cerebrospinal fluid (CSF) leak following endoscopic transnasal pituitary and anterior skull base surgery: a multivariate analysis

BACKGROUND

Post-operative CSF leak is the major source of morbidity following endoscopic transsphenoidal surgery. The purpose of this study was to identify factors associated with post-operative CSF leak in patients undergoing this surgery and facilitate the prospective identification of patients at higher risk of this complication.

METHODS

A review of a prospectively maintained database containing details of 270 endoscopic transsphenoidal operations performed by the senior author over a 9-year period was performed. Univariate analysis was performed using the Chi-squared and Fisher's exact tests, as appropriate. A logistic regression model was constructed for multivariate analysis.

RESULTS

The rate of post-operative CSF leak in this series was 9%. On univariate analysis, previous surgery, resection of craniopharyngiomas, adenomas causing Cushing's disease and intra-operative CSF leaks were associated with an increased risk of post-operative CSF leak. The use of a vascularised nasoseptal flap and increasing surgical experience were associated with a decreased rate of CSF leak. On multivariate analysis, a resection of tumour for Cushing's disease (OR 5.79, 95% CI 1.53-21.95, p = 0.01) and an intra-operative CSF leak (OR 4.56, 95% CI 1.56-13.32, p = 0.006) were associated with an increased risk of post-operative CSF leak. Increasing surgical experience (OR 0.14, 95% CI 0.04-0.46, p = 0.001) was strongly associated with a decreased risk of post-operative CSF leak.

CONCLUSIONS

Increasing surgical experience is a strong predictor of a decreased risk of developing post-operative CSF leak following endoscopic transsphenoidal surgery. Patients with Cushing's disease and those who develop an intra-operative CSF leak should be managed with meticulous skull base repair and close observation for signs of CSF leak post-operatively.

Determinants of outcome of transsphenoidal surgery for Cushing disease in a single-centre series

BACKGROUND

First-line therapy of Cushing disease (CD) is transsphenoidal surgery (TSS) aimed to obtain a complete removal of the pituitary adenoma and remission of disease.

PURPOSE

To analyse the surgical outcome of patients with CD who underwent TSS in our Centre.

METHODS

Retrospective analysis on patients with CD who underwent TSS between 1990 and 2016.

RESULTS

We analysed 102 TSS that included: 84 first TSS and 18 second and third TSS. The overall remission rate after surgery was 76.5%, with a significant higher percentage of remitted patients after the first TSS compared to the subsequent TSS (82% vs 50%, p = 0.014). The remission after the first TSS was significantly higher when performed by a dedicated surgical team (DST) (89.8% vs 71% p = 0.04) and when the immunohistochemical examination confirmed the adrenocorticotropic adenoma (87% vs 55%, p = 0.04). Neuroradiological findings influenced the surgical outcome in a non-significant manner. Post-TSS complications were reported in 32 patients, with no significant variation when TSS was performed by DST. In case of reintervention, remission of disease was obtained in 72.7% of microadenoma, while no remitted patients were observed in case of macroadenomas. The DST did not significantly improve the outcome.

CONCLUSION

Cushing disease is characterized by a broad spectrum of neuroradiological presentation. Despite the availability of a DST make the TSS a safe and effective first-line treatment among all these patients, a precise pre-treatment evaluation is needed in order to define the aim of neurosurgery and to schedule the management of recurrent disease.

Cushing's syndrome - Disease monitoring: Recurrence, surveillance with biomarkers or imaging studies

Pituitary surgery is the first-line treatment for patients with Cushing's disease. For patients who are not considered candidates for pituitary surgery, pituitary radiation and bilateral adrenalectomy are further treatment alternatives. Not all patients are cured with pituitary surgery, and a substantial number of patients develop recurrence, sometimes many years after an apparently successful treatment. The same applies to patients treated with radiotherapy. Far from all patients are cured, and in many cases the disease recurs. Bilateral adrenalectomy, although always curative, causes chronic adrenal insufficiency and the remaining pituitary tumour can continue to grow and cause symptoms due to pressure on adjacent tissues, a phenomenon called Nelson's syndrome. In this paper the rate of recurrence of hypercortisolism, as well as the rate of development of Nelson's syndrome, following treatment of patients with Cushing's syndrome, will be reviewed. The aim of the paper is also to summarize clinical and biochemical factors that are associated with recurrence of hypercortisolism and how the patients should be monitored following treatment.

Cushing's Disease

In patients with Cushing's disease (CD), prompt diagnosis and treatment are essential for favorable long-term outcomes, although this remains a challenging task. The differential diagnosis of CD is still difficult in some patients, even with an organized stepwise diagnostic approach. Moreover, despite the use of high-resolution magnetic resonance imaging (MRI) combined with advanced fine sequences, some tumors remain invisible. Surgery, using various surgical approaches for safe maximum tumor removal, still remains the first-line treatment for most patients with CD. Persistent or recurrent CD after unsuccessful surgery requires further treatment, including repeat surgery, medical therapy, radiotherapy, or sometimes, bilateral adrenalectomy. These treatments have their own advantages and disadvantages. However, the most important thing is that this complex disease should be managed by a multidisciplinary team with collaborating experts. In addition, a personalized and individual-based approach is paramount to achieve high success rates while minimizing the occurrence of adverse events and improving the patients' quality of life. Finally, the recent new insights into the pathophysiology of CD at the molecular level are highly anticipated to lead to the introduction of more accurate diagnostic tests and efficacious therapies for this devastating disease in the near future.

Current management of Cushing's disease

Cushing's disease (CD) is caused by a pituitary tumour that secretes adrenocorticotropin (ACTH) autonomously, leading to excess cortisol secretion from the adrenal glands. The condition is associated with increased morbidity and mortality that can be mitigated by treatments that result in sustained endocrine remission. Transsphenoidal pituitary surgery (TSS) remains the mainstay of treatment for CD but requires considerable neurosurgical expertise and experience in order to optimize patient outcomes. Up to 90% of patients with microadenomas (tumour below 1 cm in largest diameter) and 65% of patients with macroadenomas (tumour at or above 1 cm in greatest diameter) achieve endocrine remission after TSS by an experienced surgeon. Patients who are not in remission postoperatively or those who relapse may benefit from undergoing a second pituitary operation. Alternatively, radiation therapy to the sella with interim medical therapy, or bilateral adrenalectomy, can be effective as definitive treatments of CD. Medical therapy is currently adjunctive in most patients with CD and is generally prescribed to patients who are about to receive radiation therapy and will be awaiting its salutary effects to occur. Available treatment options include steroidogenesis inhibitors, centrally acting agents and glucocorticoid receptor antagonists. Several novel agents are in clinical trials and may eventually constitute additional treatment options for this serious condition.

A machine learning approach to predict early outcomes after pituitary adenoma surgery

OBJECTIVEPituitary adenomas occur in a heterogeneous patient population with diverse perioperative risk factors, endocrinopathies, and other tumor-related comorbidities. This heterogeneity makes predicting postoperative outcomes challenging when using traditional scoring systems. Modern machine learning algorithms can automatically identify the most predictive risk factors and learn complex risk-factor interactions using training data to build a robust predictive model that can generalize to new patient cohorts. The authors sought to build a predictive model using supervised machine learning to accurately predict early outcomes of pituitary adenoma surgery.METHODSA retrospective cohort of 400 consecutive pituitary adenoma patients was used. Patient variables/predictive features were limited to common patient characteristics to improve model implementation. Univariate and multivariate odds ratio analysis was performed to identify individual risk factors for common postoperative complications and to compare risk factors with model predictors. The study population was split into 300 training/validation patients and 100 testing patients to train and evaluate four machine learning models using binary classification accuracy for predicting early outcomes.RESULTSThe study included a total of 400 patients. The mean ± SD patient age was 53.9 ± 16.3 years, 59.8% of patients had nonfunctioning adenomas and 84.7% had macroadenomas, and the mean body mass index (BMI) was 32.6 ± 7.8 (58.0% obesity rate). Multivariate odds ratio analysis demonstrated that age < 40 years was associated with a 2.86 greater odds of postoperative diabetes insipidus and that nonobese patients (BMI < 30) were 2.2 times more likely to develop postoperative hyponatremia. Using broad criteria for a poor early postoperative outcome-major medical and early surgical complications, extended length of stay, emergency department admission, inpatient readmission, and death-31.0% of patients met criteria for a poor early outcome. After model training, a logistic regression model with elastic net (LR-EN) regularization best predicted early postoperative outcomes of pituitary adenoma surgery on the 100-patient testing set-sensitivity 68.0%, specificity 93.3%, overall accuracy 87.0%. The receiver operating characteristic and precision-recall curves for the LR-EN model had areas under the curve of 82.7 and 69.5, respectively. The most important predictive variables were lowest perioperative sodium, age, BMI, highest perioperative sodium, and Cushing's disease.CONCLUSIONSEarly postoperative outcomes of pituitary adenoma surgery can be predicted with 87% accuracy using a machine learning approach. These results provide insight into how predictive modeling using machine learning can be used to improve the perioperative management of pituitary adenoma patients.

Negative surgical exploration in patients with Cushing's disease: benefit of two-thirds gland resection on remission rate and a review of the literature

OBJECTIVEThe authors report their single-institution experience with the pathological findings, rates of remission, and complications in patients with presumed Cushing's disease (CD) who underwent a two-thirds pituitary gland resection when no adenoma was identified at the time of transsphenoidal surgery (TSS). The authors also review the literature on patients with CD, negative surgical exploration, and histological findings.METHODSThis study is a retrospective analysis of cases found in neurosurgery and pathology department databases between 1989 and 2011. In all cases, patients had been operated on by the same neurosurgeon (K.O.L.). Twenty-two (13.6%) of 161 patients who underwent TSS for CD had no adenoma identified intraoperatively after systematic exploration of the entire gland; these patients all underwent a two-thirds pituitary gland resection. A chart review was performed to assess treatment data points as well as clinical and biochemical remission status.RESULTSOf the 22 patients who underwent two-thirds gland resection, 6 (27.3%) ultimately had lesions found on final pathology. All 6 patients were found to have a distinct adrenocorticotropic hormone (ACTH) cell adenoma. Sixteen (72.7%) of the patients had no tumor identified, with 3 of these patients suspected of having ACTH cell hyperplasia. The follow-up duration for the entire group was between 14 and 315 months (mean 98.9 months, median 77 months). Remission rates were 100% (6/6 patients) for the ACTH cell adenoma group and 75% (12/16) for the group without adenoma. Overall, 18 (81.8%) of the 22 patients had no evidence of hypercortisolism at last follow-up, and 4 patients (18%) had persistent hypercortisolism, defined as a postoperative cortisol level > 5 μg/dl. Of these 4 patients, 1 was suspected of harboring a cavernous sinus adenoma, 2 were found to have lung tumors secreting ACTH, and 1 remained with an undiagnosed etiology. Rates of postoperative complications were low.CONCLUSIONSThe diagnosis and treatment of CD can be challenging for neurosurgeons, endocrinologists, and pathologists alike. Failure to find a discrete adenoma at the time of surgery occurs in at least 10%-15% of cases, even in experienced centers. The current literature provides little guidance regarding rational intraoperative approaches in such cases. The authors' experience with 161 patients with CD, when no intraoperative tumor was localized, demonstrates the utility of a two-thirds pituitary gland resection with a novel and effective surgical strategy, as suggested by a high initial remission rate and a low operative morbidity.

The Utility of Intraoperative Cytological Smear and Frozen Section in the Surgical Management of Patients with Cushing's Disease due to Pituitary Microadenomas

Cushing's disease (CD) is most commonly caused by a microadenoma, which at surgical exploration may not provide adequate tissue for pathologic diagnosis using standard techniques. We wished to determine the accuracy of intraoperative pathologic examination and whether the addition of intraoperative cytology increased the diagnostic yield. We reviewed the pathology reports from 403 operations on 341 patients with CD microadenomas from a single institution. The concordance rates of intraoperative diagnoses (cytology and frozen) with the final (paraffin section) pathological diagnosis were calculated. The overall pathologic confirmation of an adenoma (by either cytology, frozen, or paraffin section) was compared with the result from a historical cohort (using only standard frozen section analysis but not intraoperative cytology) and the pooled result from a meta-analysis of previously published data. The concordance rate between frozen section diagnosis and paraffin section histology was 390/403 (96.8%). The concordance rate between cytological smear and paraffin section histology was 213/246 (86.6%). In 54 cases (13.4%) with ultimate remission, pathologic confirmation was obtained only on intraoperative pathology (frozen section or cytology). Overall, pathologic confirmation was obtained in 326 operations (80.9%) by at least one pathological modality. The overall pathological confirmation of an adenoma was greater after the introduction of intraoperative cytology when compared with the historical control (67.1%, p = 0.015), and compared with the pooled rate of published data from the meta-analysis (72.1%, p < 0.001). Our findings suggest that addition of intraoperative cytological analyses during surgery for CD is an additional useful diagnostic tool for both neurosurgeons and pathologists.

Surgical Outcomes and Comorbidities in Cushing Disease: 30 Years of Experience in a Referral Center

OBJECTIVE

Cushing disease (CD) is a rare, poorly understood entity. Our aim was to add our clinical experience of >30 years in a multidisciplinary specialized unit to the global knowledge of CD.

METHODS

This descriptive retrospective study included all patients admitted to the Endocrinology and Nutrition Department of the Virgen del Rocío University Hospital, Seville, Spain, from January 1980 to May 2016. All patients had a definitive diagnosis of CD.

RESULTS

Total sample included 119 patients; 100 (84%) were female. Median age at diagnosis was 37.97 years (interquartile range [IQR]: 25.89-45.07 years). Median follow-up was 88 months (IQR: 45.50-157.00 months). Most tumors were microadenomas (62/95) (5.1 mm [IQR: 4.0-7.0 mm]) without sinus invasion. Surgical procedures were conventional transsphenoidal surgery (CTSS) (101/108; cured 70 after first attempt) and expanded endoscopic transsphenoidal surgery (EETSS) (7/108; cured 5 after first attempt); 11 patients did not receive surgical treatment. Fourteen patients received radiotherapy after a first surgery and 5 patients after a second surgical removal attempt. In 13 patients (12.04%), CD relapse was demonstrated after initial CTSS (median disease-free period 65 months [IQR: 45-120 months]). Ten patients developed panhypopituitarism owing to the surgical procedure (CTSS); 8 patients developed panhypopituitarism after adjuvant radiotherapy.

CONCLUSIONS

We observed slightly inferior cure rate after first surgery compared with moderately better relapse rates and time to relapse. Radiotherapy after surgery failure seemed to be more effective than CTSS; however, EETSS may be a valid alternative. Postoperative panhypopituitarism rate after first surgery was lower than expected; after radiotherapy, our results were comparable to other series.

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.

Clinical characteristics and surgical outcome in USP8-mutated human adrenocorticotropic hormone-secreting pituitary adenomas

PURPOSE

somatic mutations in the ubiquitin-specific protease 8 (USP8) gene have recently been described in patients with Cushing's disease (CD). The aim of the study is to verify whether USP8 mutation may predict early and late outcome of pituitary surgery in patients with CD operated at a single institution.

METHODS

We performed a retrospective genetic analysis of 92 adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. Specimens were screened for USP8 hotspot mutations in the exon 14 with Sanger sequencing. Hormonal and surgical data were compared between USP8 variant carriers and wild-type tumors.

RESULTS

USP8 variants were detected in 22 adenomas (23.9%) with higher prevalence in women (28.9% vs. 5.3% in men; p < 0.05). No significant difference in hormonal levels and tumoral features in relation to USP8 status was observed. Interestingly, USP8-variant carriers were more likely to achieve surgical remission than wild-type adenomas (100% vs. 75.7%; p = 0.01). Conversely, recurrence of CD occurred in 23% of USP8-mutated patients and in 13% of patients with wild-type adenoma. The recurrence-free survival did not differ significantly between the two groups (p = 0.42).

CONCLUSIONS

ACTH-secreting pituitary adenomas carrying somatic USP8 mutations are associated with a greater likelihood of surgical remission in patients operated by a single neurosurgeon. Recurrence rates are not related with USP8-variant status.

Prediction of Recurrence after Transsphenoidal Surgery for Cushing's Disease: The Use of Machine Learning Algorithms

BACKGROUND

There are no reliable predictive models for recurrence after transsphenoidal surgery (TSS) for Cushing's disease (CD).

OBJECTIVES

This study aimed to develop machine learning (ML)-based predictive models for CD recurrence after initial TSS and to evaluate their performance.

METHOD

A total of 354 CD patients were included in this retrospective, supervised learning, data mining study. Predictive models for recurrence were developed according to 17 variables using 7 algorithms. Models were evaluated based on the area under the receiver operating characteristic curve (AUC).

RESULTS

All patients were followed up for over 12 months (mean ± SD 43.80 ± 35.61). The recurrence rate was 13.0%. Age (p < 0.001), postoperative morning serum cortisol nadir (p = 0.002), and postoperative (p < 0.001) and preoperative (p = 0.04) morning adrenocorticotropin (ACTH) level were significantly related to recurrence. AUCs of the 7 models ranged from 0.608 to 0.781. The best performance (AUC = 0.781, 95% CI 0.706, 0.856) appeared when 8 variables were introduced to the random forest (RF) algorithm, which was much better than that of logistic regression (AUC = 0.684, p = 0.008) and that of using only postoperative morning serum cortisol (AUC = 0.635, p < 0.001). According to the feature selection algorithms, the top 3 predictors were age, postoperative serum cortisol, and postoperative ACTH.

CONCLUSIONS

Using ML-based models for prediction of the recurrence after initial TSS for CD is feasible, and RF performs best. The performance of most of ML-based models was significantly better than that of some conventional models.

Endoscopic vs. microscopic transsphenoidal surgery for Cushing's disease: a systematic review and meta-analysis

PURPOSE

Systematic review and meta-analysis comparing endoscopic and microscopic transsphenoidal surgery for Cushing's disease regarding surgical outcomes (remission, recurrence, and mortality) and complication rates. To stratify the results by tumor size.

METHODS

Nine electronic databases were searched in February 2017 to identify potentially relevant articles. Cohort studies assessing surgical outcomes or complication rates after endoscopic or microscopic transsphenoidal surgery for Cushing's disease were eligible. Pooled proportions were reported including 95% confidence intervals.

RESULTS

We included 97 articles with 6695 patients in total (5711 microscopically and 984 endoscopically operated). Overall, remission was achieved in 5177 patients (80%), with no clear difference between both techniques. Recurrence was around 10% and short term mortality < 0.5% for both techniques. Cerebrospinal fluid leak occurred more often in endoscopic surgery (12.9 vs. 4.0%), whereas transient diabetes insipidus occurred less often (11.3 vs. 21.7%). For microadenomas, results were comparable between both techniques. For macroadenomas, the percentage of patients in remission was higher after endoscopic surgery (76.3 vs. 59.9%), and the percentage recurrence lower after endoscopic surgery (1.5 vs. 17.0%).

CONCLUSIONS

Endoscopic surgery for patients with Cushing's disease reaches comparable results for microadenomas, and probably better results for macroadenomas than microscopic surgery. This is present despite the presumed learning curve of the newer endoscopic technique, although confounding cannot be excluded. Based on this study, endoscopic surgery may thus be considered the current standard of care. Microscopic surgery can be used based on neurosurgeon's preference. Endocrinologists and neurosurgeons in pituitary centers performing the microscopic technique should at least consider referring Cushing's disease patients with a macroadenoma.

The experience with transsphenoidal surgery and its importance to outcomes

PURPOSE

Surgical experience is considered paramount for excellent outcome of transsphenoidal surgery (TSS). However, objective data demonstrating the surgical success in relation to the experience of pituitary surgery units or individual experience of pituitary surgeons is sparse.

METHODS

Based on literature data, we have investigated the influence of experience with TSS for pituitary adenomas on endocrinological remission rates and on operative complications. The surgical experience was assessed by calculating the number of transsphenoidal operations per year.

RESULTS

For TSS of microprolactinomas, mean remission rates were 77% in centers with < 2 operations per year for microprolactinomas, 82% with 2-4 operations, 84% with 4-6 operations, and 91% with > 6 operations. A yearly experience with more than 10 initial operations for Cushing's disease (CD) warrants a remission rate exceeding 70%. Remission rates in CD exceeding 86% have only been reported for single surgeon series. Extraordinarily high complication rates were found in some series with < 25 yearly total operations for pituitary adenomas. Major vascular complications were less than 2% and revision rates for rhinorrhea usually < 2.5% in centers performing > 25 transsphenoidal operations per year.

CONCLUSIONS

We conclude that a center with experience of > 25 transsphenoidal operations for pituitary adenomas per year provides a high likelihood of safe TSS. Surgery for CD requires a particularly high level of practice to guarantee excellent remission rates. The endocrinologist has the unique opportunity to audit the surgical success by hormone measurement and to refer patients to neurosurgeons with proven excellence.

Outcome of Transsphenoidal Surgery for Cushing Disease: A Single-Center Experience over 20 Years

BACKGROUND

This study investigated the outcome of transsphenoidal surgery (TSS) for Cushing disease (CD) and the influence of our surgical strategy on remission rates and postoperative pituitary function.

PATIENTS AND METHODS

We retrospectively reviewed data from 71 patients with CD who underwent microscope navigation TSS (MN-TSS) in Saint-Luc Hospital between 1996 and 2017. True remission was defined as normal fasting cortisol level, normal 24-hour urinary free cortisol, or continued need for hydrocortisone replacement for 1 year after surgery.

RESULTS

Overall remission rate after 1 or repeated MN-TSS was 83%. Highest remission rate was found in patients with macroadenomas (92%). Successful first MN-TSS was correlated with a high final remission rate (95%), whereas failed first MN-TSS was correlated with a low final remission rate (36%). Although day 1 cortisol levels were significantly lower in patients with long-term remission, high levels were still observed in a few patients, especially those who had had CD for many years. We found a low rate of postoperative pituitary long-term hypofunction (9.7%).

CONCLUSIONS

MN-TSS is a safe and effective procedure to treat CD, allowing remission rates of 83%. One-year remission period after first surgery is correlated with a final remission rate of 95%. Although day 1 morning cortisol value is the most significant predictor for long-term remission, some patients with CD for many years may keep high postoperative cortisol levels and be in later remission, likely because of secondary adrenal hyperplasia. Our focused approach with microscope navigation resulted in low rates of postoperative pituitary hypofunction and kept a recurrence rate comparable to that in the literature.

Transsphenoidal surgery in Cushing disease: The challenging microadenoma (Local experience)

Background: Cushing disease is uncommon challenging disease. The adenomas are usually small in size in most case making the disease diagnosis and management is sometimes difficult. In some cases, the tumor cannot be identified on imaging studies and in many cases the adenoma is eccentric in location adding more difficulties to the trans-sphenoid approach for excision of such tricky tumors.

Object: to evaluate the challenge of diagnosis and trans-sphenoid surgery for ACTH pituitary microadenomas.

Methods: 21 patients with ACTH secreting adenomas were involved in this retrospective study. All cases were operated up on via trans-sphenoid approach during the period from January 2009 till October 2015. All of them were microadenomas. All patients had obvious Cushing manifestations. In all cases magnetic resonance (MR) imaging and CT paranasal sinuses were performed. In this study: cases with macroadenomas and recurrent cases after previous trans-sphenoid approach or gamma knife radiosurgery were excluded.

Results: Among the 21 patients; 14 were female and 7 weremale with age ranging from 21 to 44 years. The imaging study was positive for microadenoma in 18 patients while in 3 cases; no tumor was seen on the MRI imaging. All were operated via the trans-sphenoid approach (12 patients via the microscopic technique and other 9 patients via the endoscopic technique). The adenoma was successfully removed in 15 out of the 18 patients with evident adenoma on pre-operative MRI imaging while partial hypophysectomy were done in 5 cases without an evident adenoma on pre-operative MRI study or difficult adenoma identification. In one patient; the procedure was aborted because of sphenoid sinus abnormalities and the tumor was successfully removed via trans-cranial approach. Disease remission was achieved in 17 patients. In 4 patients; complete remission was not achieved and gamma knife radiosurgery was done after surgery. Disease progression occurred in two patients with initial remission and was treated gamma knife radiosurgery. 13 patients had an ACTH deficiency after surgery while other hormonal replacement therapy is needed in only 5 cases. CSF rhinorrhea occurred in 2 patients and was managed with transient lumbar drain without any subsequent morbidities. Transient diabetes insipidus occurred in 6 cases and was treated conservatively.

Conclusions: The transsphenoidal approach ACTH secreting pituitary microadenomas is considered safe and effective for achieving disease remission despite the challenge of diagnosis and intra-operative tumor identification.

Neonatal Cushing Syndrome: A Rare but Potentially Devastating Disease

Neonatal Cushing syndrome (CS) is most commonly caused by exogenous administration of glucocorticoids and rarely by endogenous hypercortisolemia. CS owing to adrenal lesions is the most common cause of endogenous CS in neonates and infants, and adrenocortical tumors (ACTs) represent most cases. Many ACTs develop in the context of a TP53 gene mutation, which causes Li-Fraumeni syndrome. More rarely, neonatal CS presents as part of other syndromes such as McCune-Albright syndrome or Beckwith-Wiedemann syndrome. Management usually includes resection of the primary tumor with or without additional medical treatment, but manifestations may persist after resolution of hypercortisolemia.

USP8 Mutations in Pituitary Cushing Adenomas-Targeted Analysis by Next-Generation Sequencing

Gain-of-function somatic mutations in the ubiquitin specific protease 8 (USP8) gene have recently been reported as a cause of pituitary adenomas in Cushing disease. Molecular diagnostic testing of tumor tissue may aid in the diagnosis of specimens obtained through therapeutic transsphenoidal surgery; however, for small tumors, availability of fresh tissue is limited, and contamination with normal tissue is frequent. We performed molecular testing of DNA isolated from single formalin-fixed and paraffin-embedded (FFPE) tissue sections of 42 pituitary adenomas from patients with Cushing disease (27 female patients and 15 male patients; mean age at surgery, 42.5 years; mean tumor size, 12.2 mm). By Sanger sequencing, we identified previously reported USP8 missense mutations in six tumors. Targeted next-generation sequencing (NGS) revealed known or previously undescribed missense mutations in three additional tumors (two with two different mutations each), with mutant allele frequencies as low as 3%. Of the nine tumors with USP8 mutations (mutation frequency, 21.4%), seven were from female patients (mutation frequency, 25.9%), and two were from male patients (mutation frequency, 13.3%). Mutant tumors were on average 11.4 mm in size, and patients with mutations were on average 43.9 years of age. The overall USP8 mutation frequency in our cohort was lower than in previously described cohorts, and we did not observe USP8 deletions that were frequent in other cohorts. We demonstrate that testing for USP8 variants can be performed from small amounts of FFPE tissue. NGS showed higher sensitivity for USP8 mutation detection than did Sanger sequencing. Assessment for USP8 mutations may complement histopathological diagnosis.

Outcome of endoscopic vs microsurgical transsphenoidal resection for Cushing's disease

INTRODUCTION

It is unclear whether the proportions of remission and the recurrence rates differ between endoscopic transsphenoidal surgery (TS) and microscopic TS in Cushing's disease (CD); thus, we conducted a systematic review and meta-analysis to evaluate studies of endoscopic TS and microscopic TS.

METHODS

We conducted a comprehensive search of PubMed to identify relevant studies. Remission and recurrence were used as outcome measures following surgical treatment of CD.

RESULTS

A total of 24 cohort studies involving 1670 adult patients were included in the comparison. Among these studies, 702 patients across 9 studies underwent endoscopic TS, and 968 patients across 15 studies underwent microscopic TS. Similar baseline characteristics were observed in both groups. There was no significant difference in remission between the two groups: 79.7% (95% CI: 73.1-85.0%) in the endoscopic group and 76.9% (95% CI: 71.3-81.6%) in the microscopic group (P = 0.485). It appears that patients who underwent endoscopic surgery experience recurrence less often than patients who underwent microscopic surgery, with recurrence proportions of 11.0% and 15.9%, respectively (P = 0.134). However, if follow-up time is taken into account, both groups had a recurrence rate of approximately 4% per person per year (95% CI: 3.1-5.4% and 3.6-5.1%, P = 0.651).

CONCLUSIONS

We found that remission proportion and recurrence rate were the same in patients who underwent endoscopic TS as in patients who underwent microscopic TS. The definition of diagnosis, remission and recurrence should always be considered in the studies assessing therapeutic efficacy in CD.

Duration of post-operative hypocortisolism predicts sustained remission after pituitary surgery for Cushing's disease

PURPOSE

Transsphenoidal surgery (TSS) is the primary treatment modality for Cushing's disease (CD). However, the predictors of post-operative remission and recurrence remain debatable. Thus, we studied the post-operative remission and long-term recurrence rates, as well as their respective predictive factors.

METHODS

A retrospective analysis of case records of 230 CD patients who underwent primary microscopic TSS at our tertiary care referral centre between 1987 and 2015 was undertaken. Demographic features, pre- and post-operative hormonal values, MRI findings, histopathological features and follow-up data were recorded. Remission and recurrence rates as well as their respective predictive factors were studied.

RESULTS

Overall, the post-operative remission rate was 65.6% (early remission 46%; delayed remission 19.6%), while the recurrence rate was 41% at mean follow-up of 74 ± 61.1 months (12-270 months). Significantly higher early remission rates were observed in patients with microadenoma vs macroadenoma (51.7% vs 30.6%, P = 0.005) and those with unequivocal vs equivocal MRI for microadenoma (55.8% vs 38.5%, P = 0.007). Patients with invasive macroadenoma had poorer (4.5% vs 45%, P = 0.001) remission rates. Recurrence rates were higher in patients with delayed remission than those with early remission (61.5% vs 30.8%, P = 0.001). Duration of post-operative hypocortisolemia ≥13 months predicted sustained remission with 100% specificity and 46.4% sensitivity. Recurrence could be detected significantly earlier (27.7 vs 69.2 months, P < 0.001) in patients with available serial follow-up biochemistry as compared to those with infrequent follow-up after remission.

CONCLUSION

In our study, remission and recurrence rates were similar to that of reported literature, but proportion of delayed remission was relatively higher. Negative/equivocal MRI findings and presence of macroadenoma, especially those with cavernous sinus invasion were predictors of poor remission rates. In addition to early remission, longer duration of post-operative hypocortisolism is an important predictor of sustained remission. Regular biochemical surveillance may help in identifying recurrence early.

Safety of transsphenoidal microsurgical approach in patients with an ACTH-secreting pituitary adenoma

PURPOSE

Patients affected by Cushing's disease often have important comorbidities directly linked to hypercortisolism that might enhance the operative risk. We report the safety of transsphenoidal surgery in patients affected by Cushing's disease as compared with patients with nonfunctioning pituitary adenoma.

METHODS

We have retrospectively analyzed 142 patients with Cushing's disease and 299 patients with nonfunctioning pituitary adenoma who underwent transsphenoidal surgery performed by a single experienced neurosurgeon between September 2007 and December 2014. For all of them, an intraoperative computerized anesthetic record for the automatic storage of data was available.

RESULTS

The intraoperative vital parameters and the frequency of drugs administered during anesthesia were comparable between Cushing's disease and nonfunctioning pituitary adenoma groups. The duration of surgery was similar between the two groups (41.2 ± 11.8 vs. 42.9 ± 15.6 min), while the duration of anesthesia was slightly shorter in Cushing's disease patients (97.6 ± 18.1 min) than in nonfunctioning pituitary adenoma patients (101.6 ± 20.6 min, p = 0.04). The total perioperative mortality rate was 0.2% (0% in Cushing's disease vs. 0.3% in nonfunctioning pituitary adenoma). Cushing's disease patients had surgical and medical complication rates of 3.5% each, not different from those occurring in nonfunctioning pituitary adenoma. The postoperative incidence of diabetes insipidus (10.6%) and isolated hyponatremia (10.6%) in Cushing's disease patients was significantly higher than in nonfunctioning pituitary adenoma patients (4.4 and 4.1%; p = 0.02 and p = 0.01, respectively).

CONCLUSIONS

In a large series of unselected and consecutive patients with Cushing's disease, transsphenoidal surgery performed by one dedicated experienced neurosurgeon had a reasonably low risk of complications. In particular, despite the higher burden of comorbidities typically associated with hypercortisolism, medical complications are rare and no more frequent than in patients with nonfunctioning pituitary adenoma.

Diagnosis and Outcomes of 341 Patients with Cushing's Disease Following Transsphenoid Surgery: A Single-Center Experience

BACKGROUND

Transsphenoid surgery (TSS) is a standard treatment modality for Cushing's disease (CD). However, postoperative remission and recurrence rates vary among studies. Here we analyze the diagnosis and outcomes of 341 patients with a preoperative diagnosis of CD undergoing TSS in a single center over a 3-year period.

METHODS

A total of 341 patients were enrolled. Clinical manifestations, imaging results, laboratory workups, and results of inferior petrosal sinus sampling (IPSS) were obtained. Outcomes were obtained with a follow-up length from 12 to 36 months.

RESULTS

The tumors were mainly of Knosp level 0 (68.57%). The sensitivity of MRI, combined low-dose and high-dose dexamethasone suppression test and IPSS in the diagnosis were 90.83%, 88.53% and 95.57%. The concordance of lateralization by MRI and by IPSS were 78.96% and 61.34% compared with surgery. 2.

OUTCOMES

The overall remission rate was 78.89% (N = 289). Patients undergoing the first TSS (N = 234) had a remission rate of 86.36% for macroadenomas (N = 22) and 83.2% for microadenomas (N = 212). Patients undergoing a second TSS (N = 55) had lower rate of remission of 50.00% for macroadenomas (N = 6) and 61.22% for microadenomas (N = 49). For patients with invasive tumors, the overall remission rate was 26.92% (N = 26), 20.0% for macroadenomas (n = 20) and 50.0% for microadenomas (N = 6). The recurrence rate was 2.42%.

CONCLUSIONS

Pituitary imaging, endocrinological workups and IPSS are sensitive and specific diagnostic modalities for CD, but the lateralization efficacy of MRI and IPSS are unsatisfactory. A higher rate of remission relies on gross resections of tumors.

A rare case of multiple pituitary adenomas in an adolescent Cushing disease presenting as a vertebral compression fracture

Cushing disease in children and adolescents, especially with multiple pituitary adenomas (MPAs), is very rare. We report 17-year-old boy with MPAs. He presented with a vertebral compression fracture, weight gain, short stature, headache, and hypertension. On magnetic resonance imaging (MRI), only a left pituitary microadenoma was found. After surgery, transient clinical improvement was observed but headache and hypertension were observed again after 3 months later. Follow-up MRI showed a newly developed right pituitary microadenoma 6 months after the surgery. The need for careful clinical and radiographic follow-up should be emphasized in the search for potential MPAs in patients with persistent Cushing disease.

Somatic USP8 Gene Mutations Are a Common Cause of Pediatric Cushing Disease

CONTEXT

Somatic mutations in the ubiquitin-specific protease 8 (USP8) gene have been recently identified as the most common genetic alteration in patients with Cushing disease (CD). However, the frequency of these mutations in the pediatric population has not been extensively assessed.

OBJECTIVE

We investigated the status of the USP8 gene at the somatic level in a cohort of pediatric patients with corticotroph adenomas.

DESIGN AND METHODS

The USP8 gene was fully sequenced in both germline and tumor DNA samples from 42 pediatric patients with CD. Clinical, biochemical, and imaging data were compared between patients with and without somatic USP8 mutations.

RESULTS

Five different USP8 mutations (three missense, one frameshift, and one in-frame deletion) were identified in 13 patients (31%), all of them located in exon 14 at the previously described mutational hotspot, affecting the 14-3-3 binding motif of the protein. Patients with somatic mutations were older at disease presentation [mean 5.1 ± 2.1 standard deviation (SD) vs 13.1 ± 3.6 years, P = 0.03]. Levels of urinary free cortisol, midnight serum cortisol, and adrenocorticotropic hormone, as well as tumor size and frequency of invasion of the cavernous sinus, were not significantly different between the two groups. However, patients harboring somatic USP8 mutations had a higher likelihood of recurrence compared with patients without mutations (46.2% vs 10.3%, P = 0.009).

CONCLUSION

Somatic USP8 gene mutations are a common cause of pediatric CD. Patients harboring a somatic mutation had a higher likelihood of tumor recurrence, highlighting the potential importance of this molecular defect for the disease prognosis and the development of targeted therapeutic options.

Efficacy of endoscopic endonasal transsphenoidal surgery for Cushing's disease in 230 patients with positive and negative MRI

OBJECT

The primary objective was to assess the remission rate, and the secondary objectives were to evaluate the early complications and recurrence rate and to define the predictive factors for the remission and recurrence rates.

PATIENTS AND METHODS

This prospective single-center study included 230 consecutive patients, operated on by a single surgeon for Cushing's disease via a transsphenoidal endoscopic endonasal approach, over a 6-year period (2008-2013). The patients included in this series were all adults (>18 years of age), who presented with clinical and biological characteristics of Cushing's disease confirmed based on dedicated MRI pituitary imaging. Biochemical remission was defined as a postoperative serum cortisol level <5 μg/dl on the 2nd day following surgery that required glucocorticoid replacement therapy.

RESULTS

The remission rate for the global population (n = 230) with a follow-up of 21 ± 19.2 months concerned 182 patients (79.1%) divided into 132 patients (82.5%) with positive MRI and 50 patients (71.4%) with negative MRI with no statistically significant difference (p = 0.077). Complications occurred in 77 patients with no deaths. A total of 22% of patients had transient diabetes insipidus and 6.4% long-term diabetes insipidus, and no postoperatively CSF leakage was observed. The recurrence rate was 9.8% with a mean time of 32.7 ± 15.2 months. The predictive factors for the remission rate were the presence of pituitary microadenoma and a positive histology. No risk factors were involved regarding the recurrence rate.

CONCLUSION

Whatever the MRI results, the transsphenoidal endonasal endoscopic approach remains the gold standard treatment for Cushing's disease. It was maximally effective with a remission rate of 79.1% and lower morbidity.