Epidemiology and Management Challenges in Prolactinomas.

Clinically relevant pituitary adenomas are present in about 1 per 1,000 of the general population and prolactinomas are by far the most common clinical subtype of pituitary adenomas. Usually prolactinomas affect premenopausal women and present with typical symptoms of menstrual disturbance and/or galactorrhea. They are generally managed with dopamine agonists to restore fertility and to control symptoms and tumor size. In a subset of prolactinomas, however, management remains challenging. Studies in recent years have identified the factors related to dopamine agonist resistance, such as male sex, genetic features, and aggressive tumor behavior. Certain other patient groups represent particular challenges for management, such as pediatric patients and pregnant women. Treatment with dopamine agonists is usually safe and effective, and adverse effects such as clinically relevant cardiac valvular complications and impulse control disorders may occur in isolated instances. A number of important disease characteristics of prolactinomas remain to be explained, such as the difference in sex prevalence before and after menopause, the higher prevalence of macroadenomas in older males, and the biochemical mechanisms of resistance to dopaminergic agonists.

Role of MDH2 pathogenic variant in pheochromocytoma and paraganglioma patients.

PURPOSE: MDH2 (malate dehydrogenase 2) has recently been proposed as a novel potential pheochromocytoma/paraganglioma (PPGL) susceptibility gene, but its role in the disease has not been addressed. This study aimed to determine the prevalence of MDH2 pathogenic variants among PPGL patients and determine the associated phenotype. METHODS: Eight hundred thirty patients with PPGLs, negative for the main PPGL driver genes, were included in the study. Interpretation of variants of unknown significance (VUS) was performed using an algorithm based on 20 computational predictions, by implementing cell-based enzymatic and immunofluorescence assays, and/or by using a molecular dynamics simulation approach. RESULTS: Five variants with potential involvement in pathogenicity were identified: three missense (p.Arg104Gly, p.Val160Met and p.Ala256Thr), one in-frame deletion (p.Lys314del), and a splice-site variant (c.429+1G>T). All were germline and those with available biochemical data, corresponded to noradrenergic PPGL. CONCLUSION: This study suggests that MDH2 pathogenic variants may play a role in PPGL susceptibility and that they might be responsible for less than 1% of PPGLs in patients without pathogenic variants in other major PPGL driver genes, a prevalence similar to the one recently described for other PPGL genes. However, more epidemiological data are needed to recommend MDH2 testing in patients negative for other major PPGL genes.

Intensity of prolactinoma on T2-weighted magnetic resonance imaging: towards another gender difference.

INTRODUCTION: Clinical presentations of prolactinomas are quite different between genders. In comparison with women's prolactinoma, those in men showed predominance of large tumors with high prolactin (PRL) levels. This preponderance could be attributed to a greater proliferative potential of the tumors. Differences in magnetic resonance imaging (MRI) signal at diagnosis have not been yet clearly evaluated. METHODS: We conduct a retrospective study comparing MRI signal intensity (SI) on T2-weighted images (T2-WI) between 41 men and 41 women to investigate whether or not men prolactinoma present specific features. RESULTS: In addition to the size of the adenoma and PRL levels (P < 0001), prolactinomas in men also exhibit differences from those in women in signal on T2-WI on MRI (P < 0001). Women's prolactinomas are mostly of high SI on T2-WI while men's prolactinomas exhibit a more heterogeneous pattern of SI on T2-WI. Prolactinomas presenting with low SI on T2-WI are almost exclusively encountered in men. CONCLUSIONS: Presence of T2-WI hypointensities in pituitary adenoma can be predictive of a different subtype of prolactinoma almost encountered in men and possibly translate the presence of spherical amyloid deposits, in agreement with the literature.

Inconsistencies in laboratory investigations of hypertension in a young woman taking ethinylestradiol/drospirenone association.

CASE PRESENTATION: A 34-year-old woman presented to the emergency department for arterial hypertension. Blood analysis requested by the endocrinologist showed very high level of aldosterone (1805 ng/L, normal values: <264 ng/L) and high level of renin activity (2.8 ng/mL/h, normal values: 0.1-2.0 ng/mL/h). The patient reported the use of Yasmin® (ethinylestradiol 30 µg/drospirenone 3 mg) continuously (without hormone-free week between cycles) as oral contraception. Medical imaging examinations revealed no anomaly in the kidneys and the adrenal glands. On the endocrinologist advice, patient stopped the intake of Yasmin®. Aldosterone and renin levels were measured several times after the discontinuation of the oral contraception and a diminution of these levels was observed with a complete normalization of both levels 26 days after the synthetic hormones discontinuation. DISCUSSION: The literature shows that ethynilestradiol/drospirenone association can interfere with the renin-angiotensin-aldosterone system and increase the levels of aldosterone and/or renin. We reported here a clinical case illustrating the significant impact of this medication on the renin-angiotensin-aldosterone axis of a young woman. However, this association is not listed among the drugs interfering with the aldosterone and renin-level measurements. CONCLUSION: Considering the data in the literature and our clinical case, we suggest adding drospirenone and the ethinylestradiol/drospirenone association in the list of drugs interfering with aldosterone and renin level determination.

PAI-BEL: a Belgian multicentre survey of primary adrenal insufficiency.

Objective: Primary adrenal insufficiency (PAI) is a rare disease with an increasing prevalence, which may be complicated by life-threatening adrenal crisis (AC). Good quality epidemiological data remain scarce. We performed a Belgian survey to describe the aetiology, clinical characteristics, treatment regimens, comorbidities and frequency of AC in PAI. Methods: A nationwide multicentre study involving 10 major university hospitals in Belgium collected data from adult patients with known PAI. Results: Two hundred patients were included in this survey. The median age at diagnosis was 38 years (IQR 25-48) with a higher female prevalence (F/M sex ratio = 1.53). The median disease duration was 13 years (IQR 7-25). Autoimmune disease was the most common aetiology (62.5%) followed by bilateral adrenalectomy (23.5%) and genetic variations (8.5%). The majority (96%) of patients were treated with hydrocortisone at a mean daily dose of 24.5 ± 7.0 mg, whereas 87.5% of patients also received fludrocortisone. About one-third of patients experienced one or more AC over the follow-up period, giving an incidence of 3.2 crises per 100 patient-years. There was no association between the incidence of AC and the maintenance dose of hydrocortisone. As high as 27.5% of patients were hypertensive, 17.5% had diabetes and 17.5% had a diagnosis of osteoporosis. Conclusion: This study provides the first information on the management of PAI in large clinical centres in Belgium, showing an increased frequency of postsurgical PAI, a nearly normal prevalence of several comorbidities and an overall good quality of care with a low incidence of adrenal crises, compared with data from other registries.

The clinical and therapeutic profiles of prolactinomas associated with germline pathogenic variants in the aryl hydrocarbon receptor interacting protein (AIP) gene.

Introduction: Prolactinomas are the most frequent type of pituitary adenoma encountered in clinical practice. Dopamine agonists (DA) like cabergoline typically provide sign/ symptom control, normalize prolactin levels and decrease tumor size in most patients. DA-resistant prolactinomas are infrequent and can occur in association with some genetic causes like MEN1 and pathogenic germline variants in the AIP gene (AIPvar). Methods: We compared the clinical, radiological, and therapeutic characteristics of AIPvar-related prolactinomas (n=13) with unselected hospital-treated prolactinomas ("unselected", n=41) and genetically-negative, DA-resistant prolactinomas (DA-resistant, n=39). Results: AIPvar-related prolactinomas occurred at a significantly younger age than the unselected or DA-resistant prolactinomas (p<0.01). Males were more common in the AIPvar (75.0%) and DA- resistant (49.7%) versus unselected prolactinomas (9.8%; p<0.001). AIPvar prolactinomas exhibited significantly more frequent invasion than the other groups (p<0.001) and exhibited a trend to larger tumor diameter. The DA-resistant group had significantly higher prolactin levels at diagnosis than the AIPvar group (p<0.001). Maximum DA doses were significantly higher in the AIPvar and DA-resistant groups versus unselected. DA-induced macroadenoma shrinkage (>50%) occurred in 58.3% in the AIPvar group versus 4.2% in the DA-resistant group (p<0.01). Surgery was more frequent in the AIPvar and DA- resistant groups (43.8% and 61.5%, respectively) versus unselected (19.5%: p<0.01). Radiotherapy was used only in AIPvar (18.8%) and DA-resistant (25.6%) groups. Discussion: AIPvar confer an aggressive phenotype in prolactinomas, with invasive tumors occurring at a younger age. These characteristics can help differentiate rare AIPvar related prolactinomas from DA-resistant, genetically-negative tumors.

Corrigendum to "Migration from RIA to LC-MS/MS for aldosterone determination: Implications for clinical practice and determination of plasma and urine reference range intervals in a cohort of healthy Belgian subjects" [Clin. Mass Spectrom. 9 (2018) 7-17].

[This corrects the article DOI: 10.1016/j.clinms.2018.06.002.].

ENSAT registry-based randomized clinical trials for adrenocortical carcinoma.

Adrenocortical carcinoma (ACC) is an orphan disease lacking effective systemic treatment options. The low incidence of the disease and high cost of clinical trials are major obstacles in the search for improved treatment strategies. As a novel approach, registry-based clinical trials have been introduced in clinical research, so allowing for significant cost reduction, but without compromising scientific benefit. Herein, we describe how the European Network for the Study of Adrenal Tumours (ENSAT) could transform its current registry into one fit for a clinical trial infrastructure. The rationale to perform randomized registry-based trials in ACC is outlined including an analysis of relevant limitations and challenges. We summarize a survey on this concept among ENSAT members who expressed a strong interest in the concept and rated its scientific potential as high. Legal aspects, including ethical approval of registry-based randomization were identified as potential obstacles. Finally, we describe three potential randomized registry-based clinical trials in an adjuvant setting and for advanced disease with a high potential to be executed within the framework of an advanced ENSAT registry. Thus we, therefore, provide the basis for future registry-based trials for ACC patients. This could ultimately provide proof-of-principle of how to perform more effective randomized trials for an orphan disease.

CT Characteristics of Pheochromocytoma: Relevance for the Evaluation of Adrenal Incidentaloma.

Background: Up to 7% of all adrenal incidentalomas (AIs) are pheochromocytomas (PCCs). In the evaluation of AI, it is generally recommended that PCC be excluded by measurement of plasma-free or 24-hour urinary fractionated metanephrines. However, recent studies suggest that biochemical exclusion of PCC not be performed for lesions with CT characteristics of an adrenocortical adenoma (ACA). Aim: To determine the proportion of PCCs with ACA-like attenuation or contrast washout on CT. Methods: For this multicenter retrospective study, two central investigators independently analyzed the CT reports of 533 patients with 548 histologically confirmed PCCs. Data on tumor size, unenhanced Hounsfield units (HU), absolute percentage washout (APW), and relative percentage washout (RPW) were collected in addition to clinical parameters. Results: Among the 376 PCCs for which unenhanced attenuation data were available, 374 had an attenuation of >10 HU (99.5%). In the two exceptions (0.5%), unenhanced attenuation was exactly 10 HU, which lies just within the range of ≤10 HU that would suggest a diagnosis of ACA. Of 76 PCCs with unenhanced HU > 10 and available washout data, 22 (28.9%) had a high APW and/or RPW, suggestive of ACA. Conclusion: Based on the lack of PCCs with an unenhanced attenuation of <10 HU and the low proportion (0.5%) of PCCs with an attenuation of 10 HU, it seems reasonable to abstain from biochemical testing for PCC in AIs with an unenhanced attenuation of ≤10 HU. The assessment of contrast washout, however, is unreliable for ruling out PCC.

Absence of hypogonadism in a male patient with a giant prolactinoma: a clinical paradox.

BACKGROUND: Impotence and decreased libido are the cardinal features of prolactinomas in males. We describe the unusual clinical, pathological and biochemical features in a male patient with a giant prolactinoma and normal gonadal function. CASE REPORT: A 57 year-old man presented with visual symptoms related to a 30x25x60mm tumor of the sella and skull base. Biopsy revealed a pituitary adenoma and subsequent hormone profiles demonstrated grossly elevated serum prolactin (131,412ng/ml), LH at the upper limit of normal and normal testosterone. The patient had no symptoms of decreased libido or impotence related to this giant prolactinoma. Immunohistochemistry revealed a tumor that was positive for prolactin, alpha-subunit and LH. Cabergoline greatly reduced prolactin levels but these remained above normal. LH, testosterone and alpha-subunit levels were decreased in parallel. Loss of libido and impotence became apparent when testosterone fell below normal, a situation that resolved with further cabergoline treatment and prolactin inhibition and testosterone therapy. CONCLUSIONS: Sexual dysfunction is a hallmark of prolactinomas in males. Tumors that co-secrete prolactin and LH are extremely rare and this is the first such case reported in an adult male. In this case, normal testosterone was maintained by intact LH levels even in the face of the highest prolactin level reported to date.

Expression of Contactin 4 Is Associated With Malignant Behavior in Pheochromocytomas and Paragangliomas.

Context: Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine, usually benign, tumors. Currently, the only reliable criterion of malignancy is the presence of metastases. Objective: The aim of this study was to identify genes associated with malignancy in PPGLs. Design: Transcriptomic profiling was performed on 40 benign and 11 malignant PPGLs. Genes showing a significantly different expression between benign and malignant PPGLs with a ratio ≥4 were confirmed and tested in an independent series by quantitative real-time polymerase chain reaction (qRT-PCR). Immunohistochemistry was performed for the validated genes on 109 benign and 32 malignant PPGLs. Functional assays were performed with hPheo1 cells. Setting: This study was conducted at the Department of Pathology of the Erasmus MC University Medical Center Rotterdam Human Molecular Genetics laboratory of the de Duve Institute, University of Louvain. Patients: PPGL samples from 179 patients, diagnosed between 1972 and 2015, were included. Main outcome measures: Associations between gene expression and malignancy were tested using supervised clustering approaches. Results: Ten differentially expressed genes were selected based on messenger RNA (mRNA) expression array data. Contactin 4 (CNTN4) was overexpressed in malignant vs benign tumors [4.62-fold; false discovery rate (FDR), 0.001]. Overexpression at the mRNA level was confirmed using qRT-PCR (2.90-fold, P = 0.02; validation set: 4.26-fold, P = 0.005). Consistent findings were obtained in The Cancer Genome Atlas cohort (2.7-fold; FDR, 0.02). CNTN4 protein was more frequently expressed in malignant than in benign PPGLs by immunohistochemistry (58% vs 17%; P = 0.002). Survival after 7 days of culture under starvation conditions was significantly enhanced in hPheo1 cells transfected with CNTN4 complementary DNA. Conclusion: CNTN4 expression is consistently associated with malignant behavior in PPGLs.

Prospective, long-term study of the effect of cabergoline on valvular status in patients with prolactinoma and idiopathic hyperprolactinemia.

Since the 1990's cabergoline has been the treatment of choice in prolactinoma, as it permits rapid and effective hormonal and tumor control in most cases. Evidence of cardiac valvulopathy was demonstrated in Parkinson's disease patients treated with dopamine agonists. Retrospective studies in prolactinoma patients treated with cabergoline at lower doses did not show such an effect. However, few prospective data with long-term follow-up are available. The aim of this study was to assess the safety of cabergoline regarding cardiac valvular status during prospective follow-up in patients treated for prolactinoma or idiopathic hyperprolactinemia. We report here a series of 100 patients (71F; median age at diagnosis: 41.5 years) treated with cabergoline for endocrine diseases (prolactinoma n = 89, idiopathic hyperprolactinemia n = 11). All patients underwent complete transthoracic echocardiographic studies at baseline and during long-term prospective surveillance using the same equipment and performed by the same technicians. The median interval between baseline and last follow-up echocardiographic studies while on cabergoline was 62.5 months (interquartile range: 34.75-77.0). The median total duration of cabergoline treatment was 124.5 months (interquartile range: 80.75-188.75) and the median cumulative total dose of cabergoline was 277.8 mg (interquartile range : 121.4-437.8 mg) at last follow-up. We found no clinically relevant alterations in cardiac valve function or valvular calcifications with cabergoline treatment. Our data suggest that findings from retrospective analyses are correct and that cabergoline is a safe chronic treatment at the doses used typically in endocrinology.

PheoSeq: A Targeted Next-Generation Sequencing Assay for Pheochromocytoma and Paraganglioma Diagnostics.

Genetic diagnosis is recommended for all pheochromocytoma and paraganglioma (PPGL) cases, as driver mutations are identified in approximately 80% of the cases. As the list of related genes expands, genetic diagnosis becomes more time-consuming, and targeted next-generation sequencing (NGS) has emerged as a cost-effective tool. This study aimed to optimize targeted NGS in PPGL genetic diagnostics. A workflow based on two customized targeted NGS assays was validated to study the 18 main PPGL genes in germline and frozen tumor DNA, with one of them specifically directed toward formalin-fixed paraffin-embedded tissue. The series involved 453 unrelated PPGL patients, of whom 30 had known mutations and were used as controls. Partial screening using Sanger had been performed in 275 patients. NGS results were complemented with the study of gross deletions. NGS assay showed a sensitivity ≥99.4%, regardless of DNA source. We identified 45 variants of unknown significance and 89 pathogenic mutations, the latter being germline in 29 (7.2%) and somatic in 58 (31.7%) of the 183 tumors studied. In 37 patients previously studied by Sanger sequencing, the causal mutation could be identified. We demonstrated that both assays are an efficient and accurate alternative to conventional sequencing. Their application facilitates the study of minor PPGL genes, and enables genetic diagnoses in patients with incongruent or missing clinical data, who would otherwise be missed.

Efficacy and safety of mitotane in the treatment of adrenocortical carcinoma: A retrospective study in 34 Belgian patients.

OBJECTIVES: Evaluation of patient characteristics and mitotane use in the treatment of adrenocortical carcinoma (ACC) over a 4-year period in Belgium. MATERIAL AND METHODS: This was a multicentre retrospective review of the outcome of 34 patients treated with mitotane for ACC during the period [01/2008-12/2011] (12 diagnosed before and 22 diagnosed during the study period) and evaluated up to 06/2013. RESULTS: Patient and tumour characteristics were consistent with those generally described for ACC. Mean age at diagnosis was 46.5 years, most patients were female (62%), had functioning ACC (65%) and advanced tumours (ENSAT stages III or IV: 82%). Therapeutic mitotane plasma levels (14-20 mg/L) were achieved at least once in 70% of the cohort, after a median of 4 months, and were maintained for more than 2 months in 61% of evaluable patients. Mitotane-related adverse effects were observed in 66% of patients, were never serious, and included gastrointestinal, neurological, neuropsychological, hormonal, dermatologic and metabolic effects. Most patients (88%) discontinued mitotane, mainly due to tumour progression. Multivariate analysis showed that ENSAT stage was a prognostic factor for overall (OS) and disease-free survival (DFS); OS was also influenced independently by achievement of therapeutic mitotane plasma levels for at least two consecutive months. CONCLUSION: Patient and tumour characteristics were consistent with previously published data. OS and DFS were mostly influenced by ENSAT stage at diagnosis. Achieving therapeutic levels of mitotane for at least two consecutive months seemed to positively influence OS, but such levels were not reached or sustained in some patients.

Challenges and controversies in the treatment of prolactinomas.

Recent studies have reported a higher prevalence of pituitary tumors than previously thought. Among these tumors, prolactinomas occur in up to 66% of cases. Since the mid-1980s, the widespread use of dopamine agonists has facilitated the management of the majority of prolactinomas, allowing biological and tumoral control in most cases. The less frequent cases of resistant prolactinomas remain challenging despite a multimodal therapy approach. The understanding of genetic alterations in familial and aggressive pituitary tumors provides new perspectives in the management of some prolactinomas. Genetic screening should be considered, particularly in familial cases but also in young patients with macroprolactinomas, as some mutations can predict potential aggressiveness.

The third/second generation PTH assay ratio as a marker for parathyroid carcinoma: evaluation using an automated platform.

BACKGROUND: Parathyroid carcinoma (PCa) is rare and often difficult to differentiate initially from benign disease. Because PCa oversecretes amino PTH that is detected by third-generation but not by second-generation PTH assays, the normal 3rd/2nd generation PTH ratio (<1) is inverted in PCa (ie, >1). OBJECTIVE: The objective of the investigation was to study the utility and advantages of automated 3rd/2nd generation PTH ratio measurements using the Liaison XL platform over existing manual techniques. SETTING: The study was conducted at a tertiary-referral academic center. DESIGN: This was a retrospective laboratory study. SUBJECTS: Eleven patients with advanced PCa (mean age 56.0 y). The controls were patients with primary-hyperparathyroidism (n = 144; mean age 53.8 y), renal transplantation (n = 41; mean age 50.6 y), hemodialysis (n = 80; mean age 65.2 y), and healthy elderly subjects (n = 40; mean age 72.6 y). RESULTS: The median (interquartile range) 3rd/2nd generation PTH ratio was 1.16 (1.10-1.38) in the PCa group, which was significantly higher than the control groups: hemodialysis: 0.74 (0.71-0.75); renal transplant: 0.77 (0.73-0.79); primary hyperparathyroidism: 0.76 (0.74-0.78); healthy elderly: 0.80 (0.74-0.83). An inverted 3rd/2nd-generation PTH ratio (>1) was seen in 9 of 11 PCa patients (81.8%) and in 7 of 305 controls (2.3%): 3 of 80 hemodialysis (3.8%), and 4 of 144 primary-hyperparathyroidism patients (2.8%). Of four PCa patients who had a normal PTH ratio with the manual method, two had an inverted 3rd/2nd-generation PTH ratio with the automated method. CONCLUSIONS: Study of the 3rd/2nd-generation PTH ratio in large patient populations should be feasible using a mainstream automated platform like the Liaison XL. The current study confirms the utility of the inverted 3rd/2nd-generation PTH ratio as a marker of PCa (sensitivity: 81.8%; specificity: 97.3%).