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

An objective way to predict remission and relapse in Cushing disease using Bayes' theorem of probability

OBJECTIVE

In this study on patients with Cushing disease, post-transsphenoidal surgery (TSS), we attempt to predict the probability of remaining in remission, at least for a year and relapse after that, using Bayes' theorem and the equation of conditional probability. The number of parameters, as well as the weightage of each, is incorporated in this equation.

DESIGN AND METHODS

The study design was a single-centre ambispective study. Ten clinical, biochemical, radiological and histopathological parameters capable of predicting Cushing disease remission were identified. The presence or absence of each parameter was entered as binary numbers. Bayes' theorem was applied, and each patient's probability of remission and relapse was calculated.

RESULTS

A total of 145 patients were included in the study. ROC plot showed a cut-off value of the probability of 0.68, with a sensitivity of 82% (range 73-89%) and a specificity of 94% (range 83-99%) to predict the probability of remission. Eighty-one patients who were in remission at 1 year were followed up for relapse and 23 patients developed relapse of the disease. The Bayes' equation was able to predict relapse in only 3 out of 23 patients.

CONCLUSIONS

Using various parameters, remission of Cushing disease can be predicted by applying Bayes' theorem of conditional probability with a sensitivity and a specificity of 82% and 94%, respectively. This study provided an objective way of predicting remission after TSS and relapse in patients with Cushing disease giving a weightage advantage to every parameter.

Intensity-modulated radiotherapy for cushing's disease: single-center experience in 70 patients

Context

Intensity-modulated radiotherapy (IMRT) is a modern precision radiotherapy technique for the treatment of the pituitary adenoma.

Objective

Aim to investigate the efficacy and toxicity of IMRT in treating Cushing's Disease (CD).

Methods

70 of 115 patients with CD treated with IMRT at our institute from April 2012 to August 2021 were included in the study. The radiation doses were usually 45-50 Gy in 25 fractions. After IMRT, endocrine evaluations were performed every 6 months and magnetic resonance imaging (MRI) annually. Endocrine remission was defined as suppression of 1 mg dexamethasone test (DST) or normal 24-hour urinary free cortisol level (24hUFC). The outcome of endocrine remission, endocrine recurrence, tumor control and complications were retrieved from medical record.

Results

At a median follow-up time of 36.8 months, the endocrine remission rate at 1, 2, 3 and 5 years were 28.5%, 50.2%, 62.5% and 74.0%, respectively. The median time to remission was 24 months (95%CI: 14.0-34.0). Endocrine recurrence was found in 5 patients (13.5%) till the last follow-up. The recurrence-free rate at 1, 2, 3 and 5 years after endocrine remission was 98.2%, 93.9%, 88.7% and 88.7%, respectively. The tumor control rate was 98%. The overall incidence of new onset hypopituitarism was 22.9%, with hypothyroidism serving as the most common individual axis deficiency. Univariate analysis indicated that only higher Ki-67 index (P=0.044) was significant favorable factors for endocrine remission.

Conclusion

IMRT was a highly effective second-line therapy with low side effect profile for CD patients. Endocrine remission, tumor control and recurrence rates were comparable to previous reports on FRT and SRS.

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.

Transsphenoidal Surgery of Corticotroph Adenomas With Cavernous Sinus Invasion: Results in a Series of 86 Consecutive Patients

Objective

Transsphenoidal surgery (TSS) is the first-line treatment for corticotroph adenomas. Although most corticotroph adenomas are noninvasive microadenomas, a small subset of them invading cavernous sinus (CS) is notoriously difficult to manage. The aim of this study was to evaluate the surgical outcome of corticotroph adenomas with CSI from a single center.

Patients and Methods

The clinical features and outcomes of CD patients who underwent TSS between January 2000 and September 2019 at Peking Union Medical College Hospital were collected from medical records. The clinical, endocrinological, radiological, histopathological, and surgical outcomes, and a minimum 12-month follow-up of patients with corticotroph adenomas invading CS were retrospectively reviewed.

Results

Eighty-six patients with corticotroph adenomas invading CS were included in the study. The average age at TSS was 37.7 years (range, 12 to 67 years), with a female-to-male ratio of 3.1:1 (65/21). The median duration of symptoms was 52.6 months (range, 1.0 to 264 months). The average of maximum diameter of tumor was 17.6 mm (range, 4.5–70 mm). All included 86 patients underwent TSS using a microscopic or an endoscopic approach. Gross total resection was achieved in 63 patients (73.3%), subtotal resection was attained in 18 (20.9%), and partial resection was achieved in 5 (5.8%). After surgery, the overall postoperative immediate remission rate was 48.8% (42/86); 51.2% (44/86) of patients maintained persistent hypercortisolism. In 42 patients with initial remission, 16.7% (7/42) experienced a recurrence. In these patients with persistent disease and recurrent CD, data about further treatment were available for 30 patients. Radiotherapy was used for 15 patients, and 4 (26.7%) of them achieved biochemical remission. Repeat TSS was performed in 5 patients, and none achieved remission. Medication was administered in 4 patients, and one of them obtained disease control. Adrenalectomy was performed in 6 patients, and 5 (83.3%) achieved biochemical remission. At the last follow-up, 10 of 30 patients (33.3%) were in remission, and 20 patients still had persistent disease.

The remission rate in corticotroph adenomas with cavernous sinus invasion (CSI) that underwent gross total resection and first TSS was significantly higher than that in patients undergoing subtotal resection, partial resection, and a second TSS (all p < 0.05). However, there was no significant difference in the remission rate between patients with different tumor sizes, Knosp grades, and surgical approaches (p > 0.05).

Conclusion

The management of corticotroph adenomas with CSI remain a therapeutic challenge due to incomplete resection of invasive and/or a large adenoma. With the application of multiple techniques, approximately half of the patients could achieve gross total resection and biochemical remission via TSS by experienced neurosurgeons. The extent of tumor resection and the number of operations were associated with surgical remission rate in corticotroph adenomas with CSI. If the remission was not achieved by surgery, other treatments including radiotherapy, medical therapy, and even bilateral adrenalectomy are required.

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.

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.

Presurgical predictive factors of surgical remission in Cushing's disease. Study of 32 cases

PURPOSE

Identify presurgical factors associated with surgical remission in Cushing's disease (CD).

METHODS

All the patients with ACTH-dependent Cushing's Syndrome in follow-up at our centre between 2014-2021 (n=40) were identified. Those patients with CD diagnosis who underwent transsphenoidal surgery by the same neurosurgeon (n=32) were included. Surgical remission was defined as plasma cortisol <1.8μg/dl and normal or low urinary free cortisol (UFC) after surgery.

RESULTS

Sixty-three per cent (n=20) were women, and the mean age at diagnosis was 42.3±17.9 years. Six patients had macroadenomas, 17 had microadenomas, and in the other 9 patients, no pituitary lesion was identified on the MRI. Seven patients were previously operated on in another centre. Surgical remission was achieved in 75% (n=24). Only three patients experienced recurrence. No association between pre-surgical demographic (age, sex, comorbidities) or hormonal (UFC, ACTH, late-night salivary cortisol levels) characteristics and the probability of surgical remission was observed. The only variable associated with a greater chance of remission was the presurgical visualisation of the adenoma on MRI (OR 8.3, P=0.02). It was also observed that patients with a history of a previous pituitary surgery had a lower tendency to achieve remission, although statistical significance was not reached (OR 0.17, P=0.09).

CONCLUSIONS

In our experience, 75% of patients with CD achieved biochemical cure after the intervention. Surgical remission was up to eight times more frequent in those patients in whom the adenoma was visualised before the intervention, but no other presurgical predictive factors of cure were identified.

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.