Low immediate postoperative serum-cortisol nadir predicts the short-term, but not long-term, remission after pituitary surgery for Cushing's disease

Glucocorticoid withdrawal syndrome: what to expect and how to manage

PURPOSE OF REVIEW

Glucocorticoid withdrawal syndrome (GWS) can develop after withdrawing exposure to supraphysiological levels of endogenous or exogenous glucocorticoids due to an established physical dependence. It is characterised by symptoms similar to adrenal insufficiency but needs to be regarded as a separate entity. GWS is often under-recognised in clinical practice and affected patients can experience significant impairment in their quality of life.

RECENT FINDINGS

A cornerstone in GWS management is adequate patient education and reassurance that symptoms are expected and typically temporary. Patients with endogenous Cushing's syndrome need to be aware that psychopathology may persist into the postoperative period. GWS is more likely to develop in severe Cushing's syndrome and in patients with very low levels of cortisol after surgery. Postoperatively, glucocorticoid replacement should be initiated and tapered in an individualised approach but there is currently no consensus on the best tapering strategy. If symptoms of GWS develop, glucocorticoid replacement ought to be temporarily increased to the previous, well tolerated dose. No randomised studies have thus far compared regimens for withdrawing glucocorticoids after treatment for anti-inflammatory or immunosuppressive causes to determine the best and safest tapering strategy. One open-label, single-arm trial in patients with asthma has recently proposed a personalised glucocorticoid tapering regimen which included the systematic assessment of adrenal function.

SUMMARY

Awareness of GWS by treating physicians and patient education are essential. Evidence on optimal GWS management after Cushing's syndrome treatment is scarce, but new data are emerging for tapering after long-term glucocorticoid treatment.

Predictive Value of Early Postoperative Course of Serum Cortisol After Transsphenoidal Surgery for Cushing’s Disease

Objective To identify early available predictors for the long-term outcome of patients after transsphenoidal surgery (TSS) in the management of Cushing’s disease.

Methods This single-center, retrospective study included 93 consecutive patients with Cushing’s disease (follow-up 12–129 months, mean 48, median 38) who underwent TSS (21 had previous operations elsewhere). Six cases had early re-operation, and the resulting data were evaluated instead of the respective first operation. During the postoperative course, serum cortisol levels were assessed every four hours at least until the next morning. An association of parameters with long-term outcomes was tested using binary logistic regression. Receiver operating characteristic curves were used to determine sensitivity, specificity, positive predictive value, and negative predictive value of different cut-off values of serum cortisol in the postoperative course in the event of recurrence after remission.

Results Eighty out of 93 patients (86%) showed postoperative remission (after primary treatment, 60 out of 72 patients, 90.3%). Of these, 8 patients (10%) developed recurrence of hypercortisolism. Compared to patients with persisting long-term remission, those with recurrence differed in cortisol levels starting from 4 pm on the day of surgery plus an event of increasing cortisol during the early postoperative course (“peak”). Binary logistic regression showed the association between a peak of serum cortisol in the early postoperative course with an increased probability of recurrence.

Conclusions Patients with a peak of serum cortisol in the early postoperative course show an increased recurrence rate. A cut-off value of serum cortisol for clear identification of patients with later recurrence could not be determined.

Glucocorticoid Withdrawal Syndrome following treatment of endogenous Cushing Syndrome

PURPOSE

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Predictive factors for recurrence of Cushing's disease after pituitary surgery

INTRODUCTION

The first-line treatment for Cushing's disease (CD) is transsphenoidal excision of the corticotropic adenoma.

AIM

To identify the predictive factors of recurrence of corticotropic adenomas after pituitary surgery.

METHODS

This is a retrospective and longitudinal study conducted in 28 patients operated for corticotropic adenoma between 1987 and 2014 and followed up in the department of endocrinology of La Rabta Hospital in Tunis (Tunisia). The mean duration of follow-up was 82 ± 65.9 months. The population was subdivided into two groups according to the occurrence or not of a recurrence. Recurrence was defined by hormonally confirmed postoperative recurrence of Cushing's syndrome.

RESULTS

The mean age of the patients was 30.8±11.8 years (24 women and 4 men). CD was related to a microadenoma in 46% of cases (n=13) and a macroadenoma in 54% of cases (n=15). The recurrence rate was 28% (n=8/28). The mean time to diagnosis of recurrence was 5.6±4 years. The sex ratio (F/M) was 7 in the recurrence group (R) and 5.6 in the non-recurrence group (NR); p= NS. The mean age of patients in the (R) group was 27.2±11.8 years and 32.2±11.9 years in the (NR) group; p= NS. The recurrence rate was 63% in case of macroadenoma and 37% in case of microadenoma; p= NS. Postoperative cortisolemia was significantly higher in the recurrence group (23.2 ± 13.5 µg/dl vs 4.4 ± 3.9 µg/dl; p 4.4 µg/dl was significantly associated with recurrence (100% vs 26.3%; p= 0.001). The duration of corticotropic axis inertia was 67.2 ± 47.7 months in the (R) group versus 88.37 ± 72.14 months in the (NR) group; p= NS.

CONCLUSIONS

Nearly a quarter of patients operated for CD develop a recurrence within five years. A postoperative cortisol level > 4.4 µg/dl is predictive of disease recurrence. Multicenter studies and a larger sample are needed to support these results.

Efficacy of endoscopic transsphenoidal surgery for cushing's disease: Case series and review of the literature

Background

This study was performed to examine the efficacy of endoscopic transsphenoidal surgery (ETS) for Cushing's disease at a single institute and to review past reports.

Material and Methods

We studied eight consecutive patients who underwent ETS for Cushing's disease. The radiological evaluation comprised a detailed examination of preoperative magnetic resonance images (MRIs), including inferior petrosal sinus sampling, for cases with normal renal function. Remission was evaluated at least three months after surgery and was defined by the presence of hypocortisolemia that required steroid replacement therapy or eucortisolemia with suppression to <1.8 μg/dL after 1mg of dexamethasone.

Results

In all cases preoperative MRI was abnormal and included two macroadenomas (25 %). Pathological confirmation of an adenoma was possible in all patients. The mean follow-up period was 5.6 (2-7) years. Remission was confirmed in 75.0% of the cases and was higher in rate for microadenoma (100%) than for macroadenoma (50%). Postoperatively , no cerebrospinal fluid rhinorrhea occurred, but new endocrine deficits were noted in 25% of patients.

Conclusion

Based on this study, ETS enhanced the intrasellar identification of adenomatous tissue, which led to low remission and complication rates that were comparable with those of traditional microsurgery for Cushing's disease.

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.

Prediction of recurrence and remission within 3 years in patients with Cushing disease after successful transnasal adenomectomy

BACKGROUND

Some laboratory and clinical features are associated with a probability of recurrence after transnasal adenomectomy for Cushing disease (CD). However, there is no consensus on a set of predictors. Rules for prediction of recurrence were not proposed earlier.

AIM

To develop prediction model of recurrence/remission after successful neurosurgical treatment for CD.

METHODS

Retrospective single-site comparative study included 349 patients (52 men and 297 women) with a verified diagnosis of CD who underwent effective endoscopic transsphenoidal adenomectomy between 2007 and 2014. Clinical and laboratory parameters were evaluated. Laboratory tests were performed using immunochemiluminescent method. Time-to-event analysis and ROC-analysis were applied. Multivariate models were developed using logistic regression and artificial neural network (ANN).

RESULTS

Postoperative cortisol and ACTH levels and their combinations cannot be used for prediction of recurrence. ANN for prediction of recurrence within 3 years after successful surgery was developed. Input variables are age, duration of the disease, MRI data on adenoma, morning postoperative levels of ACTH and cortisol, output variable is binary (recurrence/remission). Predictive value for remission is 93%, 95% CI [89%; 96%], and predictive value for recurrence is 85%, 95% CI [71%; 94%]. Web-calculator based on the model is developed and free for use.

CONCLUSION

Effective method for prediction of recurrence and long-term remission within 3 years after successful endoscopic transsphenoidal adenomectomy is proposed.

Prognostic usefulness of ACTH in the postoperative period of Cushing's disease

OBJECTIVES

To analyze the usefulness of plasma ACTH in predicting CD remission after surgery and to evaluate the prognostic usefulness of ACTH measurement after the cortisol and ACTH nadir (48 h prior to discharge).

DESIGN

A prospective study was made of 65 patients with CD operated upon between 2005 and 2016.

METHODS

Postsurgery plasma ACTH and cortisol were measured every 6 h, in the absence of corticosteroid coverage. Hydrocortisone was started in the presence of adrenal insufficiency or cortisol <55.2 nmol/L. Plasma ACTH was again determined before discharge.

MAIN OUTCOME MEASURE

Usefulness of plasma ACTH in predicting CD remission.

RESULTS

Remission at 3 months of CD was achieved in 56 of 65 cases, with late recurrence in 18 of 58 cases. Following resection, the ACTH nadir was significantly lower referred to late remission (2.8 vs 6.5 pmol/L; P = 0.031) and higher for recurrence (2.1 vs 4.8 pmol/L; P < 0.001), and identical results were obtained for the ACTH values before discharge. In the analysis of the ROC curves, nadir and before discharge ACTH values <1.9 pmol/L and <2.6 pmol/L were respectively indicative of early remission (AUC 0.827; P < 0.001); <6.2 pmol/L of remission at 3 months (AUC 0.847; P = 0.001) and >3.2 pmol/L of recurrence (AUC 0.810; P < 0.001) in both ACTH values. A time to ACTH nadir <46 h was indicative of early remission (AUC 0.751; P = 0.001), while a time >39 h was indicative of recurrence (AUC 0.773; P = 0.001).

CONCLUSIONS

We propose an ACTH value <3.3 pmol/L as a good long-term prognostic marker in the postoperative period of CD. Reaching the ACTH nadir in less time is associated to a lesser recurrence rate.

Evaluation of different hydrocortisone treatment strategies in transsphenoidal pituitary surgery

Background

Hydrocortisone treatment in transsphenoidal pituitary surgery has been debated. Although several publications advocate restrictive treatment, centers around the world administer stress doses of hydrocortisone in patients with presumed intact cortisol production. Our aim with this analysis was to compare postoperative hypocortisolism in patients who received three different protocols of hydrocortisone therapy during and after surgery.

Method

This was a retrospective observational study. Based on perioperative hydrocortisone dose given, patients were divided in three groups: high dose (HD), intermediate dose (ID), and low dose (LD). Postoperative evaluation of the pituitary function was performed using S-cortisol at day 4 and short Synacthen test (SST) at 6–8 weeks. Patients with ACTH-producing adenomas or preoperative hydrocortisone treatment were excluded.

Result

There was no difference between the groups regarding failure rate of SST. The rate of failed SST (all groups) was 51/186 (27%), 24/74 (32%) in the HD group and 26/74 (35%) and 11/38 (29%) in the ID and LD groups respectively. There was no significant difference between the ID and LD groups regarding S-cortisol at postoperative day 4 regarding serum cortisol level below 200 nmol/L. There was a significant but weak correlation, r_s 0.330 (P < 0.01) between S-cortisol day 4 and SST at 4–6 weeks.

Conclusions

Peri and postoperative hydrocortisone treatment did not affect SST response 6–8 weeks postoperatively, whereas the rate of patients with S-cortisol below 200 nmol/L at postoperative day 4 did. LD hydrocortisone therapy seems to favor a better endogenous production in the early postoperative phase.

An early post-operative ACTH suppression test can safely predict short- and long-term remission after surgery of Cushing's disease

PURPOSE

The present study evaluates the usefulness of an ACTH suppression test shortly after surgery, and to determine optimal cut-off values of included laboratory analyses, in predicting short- and long-term remission after surgery of Cushing's disease.

METHODS

A 48 h suppression test with betamethasone 2 mg/day applied after 45 transphenoidal adenomectomies in 28 patients was evaluated. Receiver operating characteristic (ROC)-curves were created for the included assays: plasma cortisol, plasma adrenocorticotropic hormone (ACTH) and urinary free cortisol (UFC). Plasma levels of cortisol and ACTH were measured both at 24 and 48 h. Youden's index was used to determine cut-off with the highest sensitivity and specificity in predicting short- (3 months) and long-term (5 years or longer) remission. The area under curve (AUC) illustrated the clinical accuracy of the different assays.

RESULTS

Plasma cortisol after 24 h with betamethasone was most accurate in predicting both short- and long-term remission. 3 months remission with cut-off 107 nmol/L: sensitivity 0.85, specificity 0.94, positive predictive value (PPV) 0.96 and AUC 0.92 (95% CI 0.85-1). 5 years remission with cut-off 49 nmol/L: sensitivity: 0.94, specificity 0.93, PPV 0.88, AUC 0.98 (95% CI 0.95-1). Analyses of ACTH or UFC did not improve diagnostic accuracy.

CONCLUSIONS

A 48 h, 2 mg/day betamethasone suppression test after transphenoidal surgery of Cushing's disease could predict short- and long-term remission with a high accuracy. Suppression of plasma cortisol after 24 h with betamethasone to values excluding Cushings disease in the diagnostic setting yielded the highest accuracy in predicting long-term remission.

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.

Prognostic Factors of Long-Term Remission After Surgical Treatment of Cushing's Disease

Transsphenoidal surgery is the main treatment of patients with adrenocorticotropic hormone (ACTH)-secreting pituitary adenomas. Although biochemical remission occurs in most patients undergoing operations at specialized centers, the recurrence risk is significant. Visualization of microadenomas on preoperative imaging and confirmation of ACTH-positive adenomas have been associated with higher remission rates. Low cortisol levels in the first 2 weeks postoperatively have been associated with durable remission; however, recurrence cannot be excluded by any cortisol threshold. The decision to perform a pituitary reoperation is based on this parameter; the protocols are institution specific. Patients with Cushing's disease warrant lifelong endocrinologic surveillance.

Clinical Parameters to Distinguish Silent Corticotroph Adenomas from Other Nonfunctioning Pituitary Adenomas

BACKGROUND

It is difficult to distinguish silent corticotroph adenomas (SCAs) from other nonfunctioning pituitary adenomas (NFPAs) preoperatively. This study aimed to determine the preoperative clinical parameters associated with SCAs.

METHODS

This was a retrospective single-center study of patients who underwent surgery for NFPAs during 2011-2016 in our tertiary hospital and who had preoperative combined pituitary function test (CPFT) and immunohistochemical staining results available. After we excluded patients with increased 24-hour urinary free cortisol to preclude overt Cushing's disease, 341 patients were finally enrolled. The medical records, including the CPFT and immunohistochemistry results, of the patients were reviewed.

RESULTS

The age and tumor size were similar between patients with SCAs and other NFPAs. The SCA group had a greater proportion of women (89.2% vs. 57.6%, P < 0.001), cavernous sinus invasion (35.1% vs. 20.7%, P = 0.047), and intratumoral hemorrhage on preoperative sella magnetic resonance imaging (32.4% vs. 9.2%, P < 0.001) compared with the NFPA group. In the preoperative CPFT, the cortisol response was not significantly different between groups. However, the peak adrenocorticotropic hormone (ACTH) (67.80 ± 49.83 vs. 85.67 ± 78.97 pg/mL, P = 0.061) tended to be lower, and the ΔACTH (53.71 ± 50.14 vs. 72.67 ± 75.82 pg/mL, P = 0.046) was significantly lower in SCAs. After we excluded patients with preoperative hypopituitarism caused by mass effects, the peak ACTH (69.39 ± 39.45 vs. 119.75 ± 89.84 pg/mL, P = 0.001) and ΔACTH (58.58 ± 36.51 vs. 107.66 ± 86.05 pg/mL, P = 0.001) were significantly lower in SCAs than in other NFPAs.

CONCLUSIONS

Female sex, cavernous sinus invasion, intratumoral hemorrhage on sella magnetic resonance imaging, and decreased ACTH response in the CPFT are independent indicators of SCAs.

Earlier post-operative hypocortisolemia may predict durable remission from Cushing's disease

CONTEXT

Achievement of hypocortisolemia following transsphenoidal surgery (TSS) for Cushing's disease (CD) is associated with successful adenoma resection. However, up to one-third of these patients recur.

OBJECTIVE

We assessed whether delay in reaching post-operative cortisol nadir may delineate patients at risk of recurrence for CD following TSS.

METHODS

A retrospective review of 257 patients who received 291 TSS procedures for CD at NIH, between 2003 and 2016. Early biochemical remission (serum cortisol nadir <5 μg/dL) was confirmed with endocrinological and clinical follow-up. Recurrence was detected by laboratory testing, clinical stigmata or medication dependence during a median follow-up of 11 months.

RESULTS

Of the 268 unique admissions, remission was recorded in 241 instances. Recurrence was observed in 9% of these cases with cortisol nadir ≤5 μg/dL and 6% of cases with cortisol nadir ≤2 μg/dL. The timing of hypocortisolemia was critical in detecting late recurrences. Morning POD-1 cortisol <3.3 μg/dL was 100% sensitive in predicting durable remission and morning POD-3 cortisol ≥18.5 μg/dL was 98.6% specific in predicting remote recurrence. AUROC analysis revealed that hypocortisolemia ≤5 µg/dL before 15 h (post-operative) had 95% sensitivity and an NPV of 0.98 for durable remission. Serum cortisol level ≤2 µg/dL, when achieved before 21 h, improved sensitivity to 100%.

CONCLUSIONS

In our cohort, early, profound hypocortisolemia could be used as a clinical prediction tool for durable remission. Achievement of hypocortisolemia ≤2 µg/dL before 21 post-operative hours appeared to accurately predict durable remission in the intermediate term.

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.