Influence of inferior petrosal sinus drainage symmetry on detection of adenomas in Cushing's syndrome

Morbidities and mortality among hospitalized patients with hypopituitarism: Prevalence, causes and management

Hypopituitarism is a highly heterogeneous multisystem disorder that can have a major impact on long-term morbidity and mortality, but even more so during acute medical conditions requiring hospitalization. Recent studies suggest a significant in-hospital burden with prolonged length of stay, increased rate of intensive care unit (ICU) admission, and initiation of mechanical ventilation - all of which may lead to an increased risk of in-hospital mortality. On the one hand, patients with hypopituitarism are often burdened by metabolic complications, including obesity, hypertension, dyslipidemia, and hyperglycemia, which alone, or in combination, are known to significantly alter relevant physiological mechanisms, including metabolism, innate and adaptive immune responses, coagulation, and wound healing, thereby contributing to adverse in-hospital outcomes. On the other hand, depending on the extent and the number of pituitary hormone deficiencies, early recognition of hormone deficiencies and appropriate management and replacement strategy within a well-organized multidisciplinary team are even stronger determinants of short-term outcomes during acute hospitalization in this vulnerable patient population. This review aims to provide an up-to-date summary of recent advances in pathophysiologic understanding, clinical implications, and recommendations for optimized multidisciplinary management of hospitalized patients with hypopituitarism.

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

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

The diagnostic yield of inferior petrosal sinus sampling in Cushing syndrome in the era of ovine CRH shortage

PURPOSE

The ovine corticotropin-releasing hormone (oCRH) stimulation test has been routinely used in the diagnostic work-up of ACTH-dependent Cushing syndrome (CS). With oCRH currently being out-of-stock in Europe, we aimed at evaluating the diagnostic performance of inferior petrosal sinus sampling (IPSS) without oCRH stimulation.

METHODS

We compared the values of 40 patients with ACTH-dependent CS and negative MRI findings in whom ACTH was measured before and after oCRH stimulation.

RESULTS

The ratio of central-to-peripheral ACTH measurement (IPS:P) before the combined 3, 5, and 10 min of oCRH stimulation yielded diminished sensitivity (85% vs. 97%), alongside markedly decreased specificity (57% vs. 71%), as well as reduced positive and negative predictive values (90% vs. 94% and 44% vs. 83%), respectively.

CONCLUSIONS

With the current drug shortages in Europe, ACTH measurements without oCRH stimulation in IPSS cannot be recommended. Thus, we call for desmopressin or the commercially available human CRH as a potential alternative in the confirmation of ACTH excess by IPSS in equivocal MRI findings.

Bilateral Inferior Petrosal Sinus Sampling Without Lateralization Is Less Accurate for the Diagnosis of Cushing Disease

Context

During bilateral inferior petrosal sinus sampling (BIPSS), the side-to-side adrenocorticotropic hormone (ACTH) ratio, referred to as sampling lateralization, was used to predict pituitary adenoma localization.

Objective

To investigate the potential different diagnostic accuracy of BIPSS for differentiating Cushing disease (CD) and ectopic ACTH secretory syndrome (EAS) patients with low lateralization (inferior petrosal sinus [IPS]:IPS ≤ 1.4) and high lateralization (IPS:IPS > 1.4).

Methods

This single-center retrospective study (2011-2021) included (all patients had BIPSS results and confirmed pathologic diagnoses) 220 consecutive CD patients (validation set), 30 EAS patients, and 40 of the CD patients who had digital subtraction angiography (DSA) videos (discovery set).

Results

In the discovery set, the low-lateralization CD group (n = 11) had a higher median plasma ACTH concentration (62.2, IQR 44.7-181.0 ng/L) than the high-lateralization CD group (n = 29) (33.0, IQR 18.5-59.5, P = .013). Lower IPS to peripheral ratios were observed in the low-lateralization group during BIPSS, both before and after stimulation (P = .013 and P = .028). The sensitivity of BIPSS before stimulation in differentiating CD from EAS was lower in the low-lateralization group than the high-lateralization group (54.6% vs 93.1%, P = .003), as validated in the validation set. DSA videos revealed higher vascular area difference visible in the 2 sides of the pituitary in low lateralization (median 1.2 × 105 pixels, IQR 0.5-1.8) than the high-lateralization group (0.4 × 105 pixels, IQR 0.1-0.7, P = .008). The vascular area ratio of the 2 sides was also significantly higher in low (1.55, IQR 1.31-2.20) than high lateralization (1.19, IQR 1.07-1.35, P = .010).

Conclusion

Our study suggested that low lateralization in CD patients may reduce the diagnostic sensitivity of BIPSS, which might be potentially associated with peripituitary vascular anatomy.

Prolactinomas in adolescent and elderly patients-A comparative long-term analysis

Objectives

Prolactinomas represent the most common type of secreting pituitary adenomas, yet are rarely encountered in adolescent-onset (AO; i.e. <18 years) or elderly-onset (EO; i.e. ≥65 years) cohorts. As a result, it is not clear whether long-term strategies should be focused differently at both age extremes when comparing their therapeutic outcomes. We aimed at investigating long-term endocrinological outcomes, looking for differences between the two cohorts and evaluating the dependence on continued dopamine agonist (DA) therapy.

Methods

Retrospective cross-sectional comparative study analyzing prolactinoma patients with a follow-up of ≥4 years. Clinical, radiological and biochemical characteristics were assessed at diagnosis and last follow-up. Longitudinal endocrinological outcomes between groups of extreme ages (i.e. AO and EO) and middle age (i.e. ≥18 years to 65 years) were compared. Independent risk factors for long-term dependence on DAs were calculated.

Results

Follow-up at ≥4 years was recorded for 108 prolactinoma patients; 10 patients with AO and 10 patients with EO. Compared to AO patients, EO patients were predominantly men (p = 0.003), and presented with significantly higher prolactin (PRL) levels (p = 0.05) and higher body mass index (p = 0.03). We noted a significant positive correlation between patients' PRL values and their age (r = 0.5, p = 0.03) or BMI (r = 0.6, p = 0.03). After a median follow-up of 115 months, remission was noted in 87 (83%) patients; 9 (90%) in AO patients, and 7 (70%) in EO patients (p = 0.58). Continuation of DAs was required in 4 patients (40%) with AO and 7 patients (70%) with EO (p = 0.37). Patients with elderly-onset were an independent predictor of long-term dependence on DAs (HR 2.8, 95% CI 1.1-7.2, p = 0.03).

Conclusions

Long-term control of hyperprolactinemia and hypogonadism does not differ between members of the AO and EO cohorts, and can be attained by the majority of patients. However, adjuvant DAs are often required, independent of the age of onset. Considering the clinical significance of persistent DA therapy for the control of hyperprolactinemia in many patients at both extremes of age, long-term monitoring may become recommended, in particular in patients with elderly-onset.

Machine Learning for Outcome Prediction in First-Line Surgery of Prolactinomas

BACKGROUND

First-line surgery for prolactinomas has gained increasing acceptance, but the indication still remains controversial. Thus, accurate prediction of unfavorable outcomes after upfront surgery in prolactinoma patients is critical for the triage of therapy and for interdisciplinary decision-making.

OBJECTIVE

To evaluate whether contemporary machine learning (ML) methods can facilitate this crucial prediction task in a large cohort of prolactinoma patients with first-line surgery, we investigated the performance of various classes of supervised classification algorithms. The primary endpoint was ML-applied risk prediction of long-term dopamine agonist (DA) dependency. The secondary outcome was the prediction of the early and long-term control of hyperprolactinemia.

METHODS

By jointly examining two independent performance metrics - the area under the receiver operating characteristic (AUROC) and the Matthews correlation coefficient (MCC) - in combination with a stacked super learner, we present a novel perspective on how to assess and compare the discrimination capacity of a set of binary classifiers.

RESULTS

We demonstrate that for upfront surgery in prolactinoma patients there are not a one-algorithm-fits-all solution in outcome prediction: different algorithms perform best for different time points and different outcomes parameters. In addition, ML classifiers outperform logistic regression in both performance metrics in our cohort when predicting the primary outcome at long-term follow-up and secondary outcome at early follow-up, thus provide an added benefit in risk prediction modeling. In such a setting, the stacking framework of combining the predictions of individual base learners in a so-called super learner offers great potential: the super learner exhibits very good prediction skill for the primary outcome (AUROC: mean 0.9, 95% CI: 0.92 - 1.00; MCC: 0.85, 95% CI: 0.60 - 1.00). In contrast, predicting control of hyperprolactinemia is challenging, in particular in terms of early follow-up (AUROC: 0.69, 95% CI: 0.50 - 0.83) vs. long-term follow-up (AUROC: 0.80, 95% CI: 0.58 - 0.97). It is of clinical importance that baseline prolactin levels are by far the most important outcome predictor at early follow-up, whereas remissions at 30 days dominate the ML prediction skill for DA-dependency over the long-term.

CONCLUSIONS

This study highlights the performance benefits of combining a diverse set of classification algorithms to predict the outcome of first-line surgery in prolactinoma patients. We demonstrate the added benefit of considering two performance metrics jointly to assess the discrimination capacity of a diverse set of classifiers.

Selective resection of cushing microadenoma guided by preoperative hybrid 18-fluoroethyl-L-tyrosine and 11-C-methionine PET/MRI

PURPOSE

11-C-methionine (MET)-positron emission tomography (PET) as an adjunct to magnetic resonance imaging (MRI) has been proposed as a suitable molecular imaging modality for localizing pituitary adenomas in Cushing's disease. 18-F-Fluoroethyl-L-tyrosine (FET)-PET, which is more widely available has not yet been reported in this context.

METHODS

Retrospective double-center cohort study on 15 patients who underwent transsphenoidal surgery for biochemically proven Cushing's disease between 2011 and 2019. Preoperative MET-PET/MRI and/or FET-PET/MRI were compared with intraoperative and histopathological examinations using the Mann Whitney U test and the Fisher's Exact test, along with positive predictive value calculations.

RESULTS

Fifteen patients were included, with a mean age of 47.2 (18-69) years. Six patients received either a MET-PET/MRI or a FET-PET/MRI and 3 patients both exams, respectively. 67% of the tumors were detected by MRI (MET-PET-group [56%]; FET-PET-group [78%]). All tumors were microadenomas with a mean adenoma volume of 0.19 cm³ (0.02-0.78), all of which displayed a circumscribed pathological FET- and/or MET-uptake. FET-PET/MRI results positively correlated with the localization of the tumor confirmed intraoperatively and histopathologically in all cases, resulting in a sensitivity and specificity of FET-PET/MRI for tumor localization of 100% (95% CI 66.37-100%). One MET-PET/MRI suggested a localization contralateral to the expected spot. The sensitivity and specificity of MET-PET for tumor localization hence was 89% (95% CI 51.75-99.72%).

CONCLUSIONS

Preoperative hybrid FET-PET/MRI and MET-PET/MRI have a high predictive value in localizing corticotroph adenoma for selective adenomectomy in Cushing's disease.

First-line surgery in prolactinomas: lessons from a long-term follow-up study in a tertiary referral center

CONTEXT

Although consensus guidelines recommend dopamine agonists (DAs) as the first-line approach in prolactinomas, some patients may opt instead for upfront surgery, with the goal of minimizing the need for continuation of DAs over the long term. While this approach can be recommended in selected patients with a microprolactinoma, the indication for upfront surgery in macroprolactinomas remains controversial, with limited long-term data in large cohorts. We aimed at elucidating whether first-line surgery is equally safe and effective for patients with micro- or macroprolactinomas not extending beyond the median carotid line (i.e., Knosp grade ≤ 1).

METHODOLOGY

Retrospective study of patients with prolactinomas Knosp grade ≤ 1 treated with upfront surgery. The primary endpoint was patients' dependence on DAs at last follow-up. The secondary endpoint was postoperative complications. Independent risk factors for long-term dependence on DAs were analyzed.

RESULTS

A microadenoma was noted in 45 patients (52%) and a macroadenoma in 41 (48%), with 17 (20%) harboring a Knosp grade 1 prolactinoma. Median follow-up was 80 months. First-line surgery resulted in long-term remission in 31 patients (72%) with a microprolactinoma and in 18 patients (45%) with a macroprolactinoma (p = 0.02). DA therapy was ultimately required in 11 patients (24%) with microadenomas vs. 20 (49%) with macroadenomas (p = 0.03). As for the latter, DA was required in 13 patients (76%) with Knosp grade 1 macroadenomas vs. 7 patients (29%) with Knosp grade 0 macroadenomas (p = 0.004). There was no mortality, and morbidity was minimal. Knosp grade 1 prolactinomas (OR 7.3, 95% CI 1.4-37.7, p = 0.02) but not adenoma size (i.e., macroprolactinomas) were an independent predictor of long-term dependence on DAs.

CONCLUSIONS

First-line surgery in patients with microprolactinomas or macroprolactinomas Knosp grade 0 resulted in a good chance of non-dependency on DA therapy. However, in patients with prolactinomas Knosp grade 1, first-line surgery cannot be recommended, as adjuvant DA therapy after surgery is required in the majority of them over the long term.

Lateral one-third gland resection in Cushing patients with failed adenoma identification leads to low remission rates: long-term observations from a small, single-center cohort

BACKGROUND

Currently, there are no guidelines for neurosurgeons treating patients with Cushing's disease (CD) when intraoperative adenoma identification is negative. Under these circumstances, a total hypophysectomy or hemi-hypophysectomy on the side indicated by inferior petrosal sinus sampling (IPSS) is the approach being used, although there is a subsequent risk of hypopituitarism. Data on whether one-third lateral pituitary gland resection results in cure of hypercortisolism and low rates of hypopituitarism remain inconclusive.

METHODS

Retrospective single-center study of CD patients with failed intraoperative adenoma identification and subsequent resection of the lateral one-third of the pituitary gland as predicted by IPSS. We assessed (i) histopathological findings, (ii) early and long-term remission rates, and (iii) rates of additional pituitary hormone insufficiency.

RESULTS

Ten women and three men met the inclusion criteria. At 3 months, remission was noted in six (46%) patients: three (23%) had histologically confirmed adenomas, two (15%) had ACTH hyperplasia, and one patient (8%) was positive for Crooke's hyaline degeneration. New pituitary hormone deficits were noted in two patients (15%). After a median (±SD) follow-up of 14±4 years, recurrence was noted in two (15%) patients. Long-term control of hypercortisolism was attained by 10 patients (77%), with additional therapies required in nine (69%) of them.

CONCLUSIONS

In CD patients with failed intraoperative adenoma visualization, lateral one-third gland resection resulted in low morbidity and long-term remission in 31% of patients without the need for additional therapies. Bearing in mind the sample size of this audit, the indication for lateral one-third-gland resection has to be critically appraised and discussed with the patients before surgery.

Revalidation of inferior petrosal sinus sampling: the latest results from a single-center experience

Cushing's disease (CD), which manifests as excess cortisol secretion, is caused by adrenocorticotrophic hormone (ACTH)-secreting pituitary adenomas. Such adenomas are occasionally difficult to identify on magnetic resonance imaging (MRI), and thorough endocrinological examination may be required to detect them. Inferior petrosal sinus (IPS) sampling (IPSS) has been the gold standard test for distinguishing CD from ectopic ACTH syndrome (EAS). However, IPSS is an invasive procedure, and proper catheterization is occasionally challenging due to anatomical variations. Thus, there have been ongoing debates regarding the necessity of this procedure. Here, we present our recent IPSS data derived from the analysis of 65 patients who were referred to us for possible CD between April 2018 and December 2020 after undergoing meticulous endocrinological testing. Even with detailed MRI, no obvious lesions were identified in 19 patients. IPSS performed on these 19 individuals identified an IPS-to-peripheral ACTH gradient in 15 of them. The four patients who lacked this gradient were subjected to a classical algorithm using concurrently measured prolactin levels, the results of which were consistent with their ultimately confirmed diagnoses: two true-positive and two true-negative diagnoses. These findings support the validity of the algorithm and demonstrate that the prolactin-adjusted IPS-to-peripheral ACTH ratio can improve the differentiation between CD and EAS. We had no false-negative results, but three patients were false-positive. Consequently, those three patients in which no apparent tumor was clarified during surgery could not have any endocrinological improvement postoperatively.

Impact of primary medical or surgical therapy on prolactinoma patients' BMI and metabolic profile over the long-term

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High prolactin (PRL) levels are associated with weight gain and impaired metabolic profiles.

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Long-term control of hyperprolactinemia can be attained by first-line surgery and medical therapy.

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Normalization of PRL improves patients’ BMI and fasting glucose levels.

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Marginal changes in patients’ metabolic profiles are noted regardless of the primary therapy.

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Not dopamine agonists per se, but rather the control of hyperprolactinemia plays a role in metabolic profile alterations.

Objectives

High prolactin levels have been associated with weight gain and impaired metabolic profiles. While treatment with dopamine agonists (DAs) has been shown to improve these parameters, there is a lack of surgical series on its comparative effect in prolactinoma patients.

Methods

In this retrospective, comparative study, consecutive patients with a prolactinoma were enrolled if treated with first-line transsphenoidal surgery (TSS) or with DAs. Patients with prolactinomas of Knosp grade >2 and those with a follow-up <24 months were excluded, as were patients with missing laboratory metabolic parameters at baseline and over the long-term. Effects of either treatment on BMI and the metabolic profile were analyzed, and independent risk factors for long-term obesity were calculated.

Results

Primary treatment was TSS for 12 patients (40%) and DAs for 18 patients (60%). At diagnosis, no significant differences between the two cohorts were observed with regard to adenoma size, Knosp grading, baseline prolactin (PRL) levels, prevalence of hypogonadism, or laboratory metabolic parameters. Mean follow-up was 51.9 months (range, 24–158). Over the long-term, both TSS and DAs led to the control of hyperprolactinemia (92% vs. 72%) and hypogonadism (78% vs. 83%) in the majority of patients. While a significant decrease in patients’ BMI and fasting glucose were observed, changes in the lipid profile were marginal and independent of the treatment modality. At baseline, increased BMI—but not the primary treatment strategy—was an independent predictor of long-term obesity.

Conclusions

Over the long-term, patients’ BMI and FG improve, but changes in the metabolic profile are marginal and independent of the primary treatment. It is presumable that not DAs per se, but rather the control of hyperprolactinemia plays a role in patients’ metabolic profile alterations.

Long-term IGF-1 monitoring in prolactinoma patients treated with cabergoline might not be indicated

PURPOSE

Cabergoline (CAB) therapy for prolactinomas has been associated with serum IGF-1 levels modifications, with recent reports indicating a paradoxical increase of IGF-1 levels during ongoing therapy. As a result, IGF-1 measurement has been proposed not only at diagnosis of a prolactinoma, but also during follow-up. In this follow-up study on prolactinoma patients with chronic CAB therapy, we investigated whether there are long-term changes in IGF-1 levels that necessitate continuous monitoring.

METHODS

We reviewed our institutional database on prolactinoma patients with long-term CAB therapy, in whom IGF-1 levels were measured at baseline, at 3-months follow-up and in the long term.

RESULTS

Chronic CAB therapy was noted in 20 patients (13 men, 7 women). Median (±SD) age was 43.5 ± 12.6 years. 17 (85%) patients presented with a macroprolactinoma. Median CAB treatment time was 75 ± 43 months (range 24-187). Median IGF-1 levels increased at last follow-up, though not significantly; from 122 ± 37 ng/ml (IQR 104-160 ng/ml) to 133 ± 54 (IQR 121-162 ng/ml), p = 0.10. Thereby, 18 (90%) patients showed normal serum IGF-1 levels adjusted for age, one (5%) patient above (1.05 × ULN) and 1 (5%) patient below the normal range (0.34 × ULN). No patient was or became symptomatic of acromegaly.

CONCLUSION

Our long-term results indicate that chronic treatment with CAB in prolactinoma patients does not significantly modify serum IGF-1 levels. Bearing in mind the sample size of this study, continuing IGF-1 monitoring is not indicated in prolactinoma patients with long-term CAB therapy.

Persistent bone impairment despite long-term control of hyperprolactinemia and hypogonadism in men and women with prolactinomas

While prolactinoma patients have high bone turnover, current data are inconclusive when it comes to determining whether correction of hyperprolactinemia and associated hypogandism improves osteodensitometric data in men and women over the long term. In a large cohort of including 40 men and 60 women, we studied the long-term impact of prolactinoma treatment on bone mineral density (BMD) in men versus women, assessed adverse effects of a primary surgical or medical approach, and evaluated data for risk factors for impaired BMD at last follow-up using multivariate regression analyses. Median duration of follow-up was 79 months (range 13–408 months). Our data indicate that the prevalence of impaired BMD remained significantly higher in men (37%) than in women (7%, p < 0.001), despite the fact that hyperprolactinemia and hypogonadism are under control in the majority of men. We found that persistent hyperprolactinemia and male sex were independent risk factors for long-term bone impairment. Currently, osteoporosis prevention and treatment focus primarily on women, yet special attention to bone loss in men with prolactinomas is advised. Bone impairment as “end organ” reflects the full range of the disease and could become a surrogate marker for the severity of long-lasting hyperprolactinemia and associated hypogonadism.

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.