Sleep patterns in patients treated for non-secreting intra- and parasellar tumors: A self-report case-control study.

Purpose: In this study we evaluate sleep patterns of patients treated for non-secreting intra- and parasellar tumors and age- and sex-matched healthy controls. Methods: We conducted a self-report cross-sectional case-control study with 104 patients treated for non-secreting intra- and parasellar tumors and 1800 healthy controls in an 1:8 matching. All subjects answered the Munich ChronoType Questionnaire, whereas patients were provided the Pittsburgh Sleep Quality Index, the Epworth Sleepiness Scale, the Short-Form 36 Health survey, the Beck Depression Inventory and the State-Trait Anxiety Inventory additionally. Results: Patients treated for non-secreting intra- and parasellar tumors go to bed earlier, fall asleep earlier, need less time to prepare to sleep but also to get up. Additionally, they lie and sleep longer. The subgroup analysis showed that patients with secondary adrenal insufficiency compared to controls experienced shorter daily light exposure and longer sleep latency. Higher hydrocortisone dose (>20mg) was associated with worse score in global, physical and mental health, shorter time to prepare to sleep, earlier sleep onset and longer sleep duration. Conclusion: Our study shows that patients treated for non-secreting intra- and parasellar tumors, even if successfully treated, experience altered sleep patterns compared to controls. We suggest that managing clinicians should enlighten these possible sleep alterations to their patients and use specific questionnaires to document sleep disturbances. Additionally, when treating patients surgically, especially by transcranial approach, damaging the suprachiasmatic nucleus should be avoided. Furthermore, circadian hydrocortisone replacement therapy ideally with dual-release hydrocortisone - if possible, in a dose not more than 20mg daily - that resembles physiological cortisol levels more closely may be beneficial and could improve sleep patterns and sleep-related quality of life.

TP53 mutations in functional corticotroph tumors are linked to invasion and worse clinical outcome.

Corticotroph macroadenomas are rare but difficult to manage intracranial neoplasms. Mutations in the two Cushing's disease mutational hotspots USP8 and USP48 are less frequent in corticotroph macroadenomas and invasive tumors. There is evidence that TP53 mutations are not as rare as previously thought in these tumors. The aim of this study was to determine the prevalence of TP53 mutations in corticotroph tumors, with emphasis on macroadenomas, and their possible association with clinical and tumor characteristics. To this end, the entire TP53 coding region was sequenced in 86 functional corticotroph tumors (61 USP8 wild type; 66 macroadenomas) and the clinical characteristics of patients with TP53 mutant tumors were compared with TP53/USP8 wild type and USP8 mutant tumors. We found pathogenic TP53 variants in 9 corticotroph tumors (all macroadenomas and USP8 wild type). TP53 mutant tumors represented 14% of all functional corticotroph macroadenomas and 24% of all invasive tumors, were significantly larger and invasive, and had higher Ki67 indices and Knosp grades compared to wild type tumors. Patients with TP53 mutant tumors had undergone more therapeutic interventions, including radiation and bilateral adrenalectomy. In conclusion, pathogenic TP53 variants are more frequent than expected, representing a relevant amount of functional corticotroph macroadenomas and invasive tumors. TP53 mutations associated with more aggressive tumor features and difficult to manage disease.

Health-related quality of life in patients with non-functioning pituitary adenoma: a special focus on hydrocortisone replacement dose.

PURPOSE: Patients with non-functioning pituitary adenomas (NFPA) suffer from pronounced impairments in physical and mental measures that result in an impairment of health-related quality of life (HRQOL). The role of secondary adrenal insufficiency (SAI) and especially the one of the hydrocortisone (HC) replacement dose on the HRQOL seems to be conflicting. The primary aim of this study is to assess the HRQOL in patients with NFPA in terms of presence of SAI and in patients without SAI and the secondary to explore the impact of treatment parameters such as daily HC dose. DESIGN/METHODS: In a cross-sectional study we evaluated parameters of HRQOL in 95 patients with NFPA of the Endocrine Outpatient Unit of the Max Planck Institute of Psychiatry in Munich using standardized questionnaires like Short Form (SF-36), Beck's Depression Inventory (BDI), State-Trait Anxiety Inventory (STAI), Epworth Sleepiness Scale (ESS), Pittsburgh Sleep Quality Index (PSQI) and a self-constructed questionnaire about medical history. RESULTS: We could not find any significant difference between patients with and without SAI in the standardized questionnaires in terms of HRQOL. We could show that higher doses of HC were negatively correlated with HRQOL measured by SF-36 global health score regardless of using BDI or STAI in the block (ß = - 0.397; p = 0.021, ß = - 0.390; p = 0.016, respectively). CONCLUSIONS: NFPA patients with SAI do not have a worse HRQOL than patients with NFPA and intact corticotropic axis. We could show that higher doses of HC are associated with an impaired HRQOL measured by SF-36 global and physical health score, whereas mental health score is not significantly influenced by the HC dose.

Thyroid and colorectal cancer screening in acromegaly patients: should it be different from that in the general population?

The literature on an association between acromegaly and cancer is particularly abundant on either colorectal cancer or thyroid cancer, and an endless debate is ongoing whether patients with acromegaly should be submitted to specific oncology screening and surveillance protocols. The aim of the present work is to review the most recent data on the risk of either colorectal cancer or thyroid cancer in acromegaly and discuss the opportunity for specific screening in relation to the accepted procedures in the general population.

Multivariable Prediction Model for Biochemical Response to First-Generation Somatostatin Receptor Ligands in Acromegaly.

CONTEXT: First-generation somatostatin receptor ligands (fg-SRLs) represent the mainstay of medical therapy for acromegaly, but they provide biochemical control of disease in only a subset of patients. Various pretreatment biomarkers might affect biochemical response to fg-SRLs. OBJECTIVE: To identify clinical predictors of the biochemical response to fg-SRLs monotherapy defined as biochemical response (insulin-like growth factor (IGF)-1 ≤ 1.3 × ULN (upper limit of normal)), partial response (>20% relative IGF-1 reduction without normalization), and nonresponse (≤20% relative IGF-1 reduction), and IGF-1 reduction. DESIGN: Retrospective multicenter study. SETTING: Eight participating European centers. METHODS: We performed a meta-analysis of participant data from 2 cohorts (Rotterdam and Liège acromegaly survey, 622 out of 3520 patients). Multivariable regression models were used to identify predictors of biochemical response to fg-SRL monotherapy. RESULTS: Lower IGF-1 concentration at baseline (odds ratio (OR) = 0.82, 95% confidence interval (CI) 0.72-0.95 IGF-1 ULN, P = .0073) and lower bodyweight (OR = 0.99, 95% CI 0.98-0.99 kg, P = .038) were associated with biochemical response. Higher IGF-1 concentration at baseline (OR = 1.40, (1.19-1.65) IGF-1 ULN, P ≤ .0001), the presence of type 2 diabetes (oral medication OR = 2.48, (1.43-4.29), P = .0013; insulin therapy OR = 2.65, (1.02-6.70), P = .045), and higher bodyweight (OR = 1.02, (1.01-1.04) kg, P = .0023) were associated with achieving partial response. Younger patients at diagnosis are more likely to achieve nonresponse (OR = 0.96, (0.94-0.99) year, P = .0070). Baseline IGF-1 and growth hormone concentration at diagnosis were associated with absolute IGF-1 reduction (ß = 0.90, standard error (SE) = 0.02, P ≤ .0001 and ß â€…= 0.002, SE = 0.001, P = .014, respectively). CONCLUSION: Baseline IGF-1 concentration was the best predictor of biochemical response to fg-SRL, followed by bodyweight, while younger patients were more likely to achieve nonresponse.

Hypoxia and the hypoxia inducible factor 1α activate protein kinase A by repressing RII beta subunit transcription.

Overactivation of the cAMP signal transduction pathway plays a central role in the pathogenesis of endocrine tumors. Genetic aberrations leading to increased intracellular cAMP or directly affecting PKA subunit expression have been identified in inherited and sporadic endocrine tumors, but are rare indicating the presence of nongenomic pathological PKA activation. In the present study, we examined the impact of hypoxia on PKA activation using human growth hormone (GH)-secreting pituitary tumors as a model of an endocrine disease displaying PKA-CREB overactivation. We show that hypoxia activates PKA and enhances CREB transcriptional activity and subsequently GH oversecretion. This is due to a previously uncharacterized ability of HIF-1α to suppress the transcription of the PKA regulatory subunit 2B (PRKAR2B) by sequestering Sp1 from the PRKAR2B promoter. The present study reveals a novel mechanism through which the transcription factor HIF-1α transduces environmental signals directly onto PKA activity, without affecting intracellular cAMP concentrations. By identifying a point of interaction between the cellular microenvironment and intracellular enzyme activation, neoplastic, and nonneoplastic diseases involving overactivated PKA pathway may be more efficiently targeted.

[Medical care of young women with Turner syndrome in Germany]. / Medizinische Betreuung von jungen Frauen mit Ullrich-Turner-Syndrom in Deutschland.

BACKGROUND: Many recommendations for medical care for women with Turner syndrome (TS) have been published in the past. There are no studies that analyse the care situation of the women in Germany until now. METHODS: The study was performed in 2015 based on a questionnaire that was completed by TS women (aged ≥ 18 years; median: 25 years). The questionnaire was devised by a French team and used with their permission. All women had received growth hormone treatment during childhood. The women were identified and addressed in writing through eleven cooperating centers and the support group. In all, 130 questionnaires were evaluated. RESULTS: 79 of the 130 women (61 %) stated that they had health problems. 38 % of the women were under medical care by only one physician and 42 % by two physicians. The gynecologist was mentioned most often (by 80.3 %), followed by the family physician (53.8 %). ENT was mentioned as a problem system by 35 %, but only 3 % of the women attended an ENT physician. The question as to whether at least one of the following examinations (measurements of blood pressure, blood sugar, blood fats, liver function and/or thyroid hormones, echocardiographic and/or audiogram examination) had been performed during a period of 4 years was answered as follows: blood pressure (85 %), blood sugar (47 %), blood fats (41 %), liver function (46 %), thyroid hormones (44 %), echocardiography (57 %) and audiogram (35 %). A comprehensive examination was performed in 9.8 % of the women. 103 women (80.5 %) received sexual hormone replacement therapy. 76 women were on further drugs; thyroid hormones (44 %) and antihypertensive drugs (11 %) were stated most often. CONCLUSIONS: This is the first study which analyses the current situation of medical care of TS women in Germany. Our data show that medical care of young adult TS women is not optimal. The study cannot clarify the reasons. Due to the numerous and different comorbidities, the medical care of TS women is complex and should therefore be provided multidisciplinarily by different specialists under the direction of one physician.

GEOFFREY HARRIS AWARD 2019: Translational research in pituitary tumours.

Although effective treatment regimens (surgical resection, drug treatment with dopamine agonists or somatostatin analogues, radiotherapy) have been established for the therapy of most pituitary tumours, a considerable proportion of affected patients cannot completely cured due to incomplete resection or drug resistance. Moreover, even if hormone levels have been normalized, patients with hormone-secreting tumours still show persistent pathophysiological alterations in metabolic, cardiovascular or neuropsychiatric parameters and have an impaired quality of life. In this review reasons for the discrepancy between biochemical cure and incomplete recovery from tumour-associated comorbidities are discussed and the clinical management is delineated exemplarily for patients with acromegaly and Cushing's disease. In view of the development of additional treatment concepts for the treatment of pituitary adenomas we speculate about the relevance of RSUME as a potential target for the development of an anti-angiogenic therapy. Moreover, the role of BMP-4 which stimulates prolactinoma development through the Smad signalling cascade is described and its role as putative drug target for the treatment of prolactinomas is discussed. Regarding the well-known resistance of a part of somatotropinomas to somatostatin analogue treatment, recently identified mechanisms responsible for the drug resistance are summarized and ways to overcome them in future treatment concepts are presented. Concerning novel therapeutic options for patients with Cushing's disease the impact of retinoic acid, which is currently tested in clinical studies, is shown, and the action and putative therapeutic impact of silibinin to resolve glucocorticoid resistance in these patients is critically discussed.

Insulin Resistance in Patients With Acromegaly.

Acromegaly is characterized by chronic overproduction of growth hormone (GH) that leads to insulin resistance, glucose intolerance and, ultimately, diabetes. The GH-induced sustained stimulation of lipolysis plays a major role not only in the development of insulin resistance and prediabetes/diabetes, but also in the reduction of lipid accumulation, making acromegaly a unique case of severe insulin resistance in the presence of reduced body fat. In the present review, we elucidate the effects of GH hypersecretion on metabolic organs, describing the pathophysiology of impaired glucose tolerance in acromegaly, as well as the impact of acromegaly-specific therapies on glucose metabolism. In addition, we highlight the role of insulin resistance in the development of acromegaly-associated complications such as hypertension, cardiac disease, sleep apnea, polycystic ovaries, bone disease, and cancer. Taken together, insulin resistance is an important metabolic hallmark of acromegaly, which is strongly related to disease activity, the development of comorbidities, and might even impact the response to drugs used in the treatment of acromegaly.

Heat Shock Protein 90 as a Prognostic Marker and Therapeutic Target for Adrenocortical Carcinoma.

Background: Adrenocortical carcinoma (ACC) is a rare tumor entity with restricted therapeutic opportunities. HSP90 (Heat Shock Protein 90) chaperone activity is fundamental for cell survival and contributes to different oncogenic signaling pathways. Indeed, agents targeting HSP90 function have shown therapeutic efficacy in several cancer types. We have examined the expression of HSP90 in different adrenal tumors and evaluated the use of HSP90 inhibitors in vitro as possible therapy for ACC. Methods: Immunohistochemical expression of HSP90 isoforms was investigated in different adrenocortical tumors and associated with clinical features. Additionally, a panel of N-terminal (17-allylamino-17-demethoxygeldanamycin (17-AAG), luminespib, and ganetespib) and C-terminal (novobiocin and silibinin) HSP90 inhibitors were tested on various ACC cell lines. Results: Within adrenocortical tumors, ACC samples exhibited the highest expression of HSP90ß. Within a cohort of ACC patients, HSP90ß expression levels were inversely correlated with recurrence-free and overall survival. In functional assays, among five different compounds tested luminespib and ganetespib induced a significant decrease in cell viability in single as well as in combined treatments with compounds of the clinically used EDP-M scheme (etoposide, doxorubicin, cisplatin, mitotane). Inhibition of cell viability correlated furthermore with a decrease in proliferation, in cell migration and an increase in apoptosis. Moreover, analysis of cancer pathways indicated a modulation of the ERK1/2-and AKT-pathways by luminespib and ganetespib treatment. Conclusions: Our findings emphasize HSP90 as a marker with prognostic impact and promising target with N-terminal HSP90 inhibitors as drugs with potential therapeutic efficacy toward ACC.

Driver mutations in USP8 wild-type Cushing's disease.

BACKGROUND: Medical treatment in Cushing's disease (CD) is limited due to poor understanding of its pathogenesis. Pathogenic variants of ubiquitin specific peptidase 8 (USP8) have been confirmed as causative in around half of corticotroph tumors. We aimed to further characterize the molecular landscape of those CD tumors lacking USP8 mutations in a large cohort of patients. METHODS: Exome sequencing was performed on 18 paired tumor-blood samples with wild-type USP8 status. Candidate gene variants were screened by Sanger sequencing in 175 additional samples. The most frequent variant was characterized by further functional in vitro assays. RESULTS: Recurrent somatic hotspot mutations in another deubiquitinase, USP48, were found in 10.3% of analyzed samples. Several possibly damaging variants were found in TP53 in 6 of 18 samples. USP48 variants were associated with smaller tumors and trended toward higher frequency in female patients. They also changed the structural conformation of USP48 and increased its catalytic activity toward its physiological substrates histone 2A and zinc finger protein Gli1, as well as enhanced the stimulatory effect of corticotropin releasing hormone (CRH) on pro-opiomelanocortin production and adrenocorticotropic hormone secretion. CONCLUSIONS: USP48 pathogenic variants are relatively frequent in USP8 wild-type tumors and enhance CRH-induced hormone production in a manner coherent with sonic hedgehog activation. In addition, TP53 pathogenic variants may be more frequent in larger CD tumors than previously reported.

[Life Situation of Young women with Turner Syndrome: Results of a Questionnaire-based Study in Germany]. / Lebenssituation von jungen Frauen mit Ullrich-Turner-Syndrom nach dem Ende der Wachstumshormontherapie: Ergebnisse einer Umfrage in Deutschland.

INTRODUCTION: Psychosocial problems such as anxious personality, low self-esteem, late separation from home and/or late sexual experience have been described in girls and women with Turner syndrome (TS). METHODS: The study was performed in 2015 based on a questionnaire that was sent out to 779 women with TS aged 25 years (median). The questionnaire was devised by a French team and used with their permission. In all, 130 questionnaires (16.7 %) could be evaluated. The questions from the individual topics were not always completely answered. RESULTS: (mean ± SD).: 116 women (89.9 %) were not married; 52 women (40 %) lived in their parents' home. 47.6 % had a high-school/technical diploma or university degree. 60 women (46 %) had a job; 51 women (39 %) had not completed vocational training. Puberty was induced at the age of 14.2 ± 2.1 years in 78 % of the women. 80 % of the women received hormone replacement therapy at the time of the questionnaire survey. 66 of 93 women (71 %) found that the disease had a negative influence on emotional life. "Love life and sexual relationship" was the topic mentioned most frequently by 44 women (66.6 %). 116 women answered questions on sexuality. Here, 77 % had the first French kiss at the age of 16.4 ± 3.6 years and 62.4 % had sexual intercourse for the first time at the age of 19.0 ±â€Š3.4 years. 81 % of the women stated that they had a partner relationship for more than 6 months (94 women had a male partner and 5 had a female partner). The question as to the wish to have children was answered in the affirmative by 89 of 124 women (71.8 %); 38.2 % desired spontaneous pregnancy and 44.9 % had considered in vitro fertilization or adoption. DISCUSSION: The women's answers show that care needs to be improved. There are deficits in the topics of family, emotional life, relationships, sexuality, fertility and pregnancy. Therefore, the medical team should also include psychologists and social workers.

Does sex hormone treatment reverse the sex-dependent stress regulation? A longitudinal study on hypothalamus-pituitary-adrenal (HPA) axis activity in transgender individuals.

BACKGROUND: Studies in mammals indicate a role for sex hormones in the regulation of hypothalamic-pituitary-adrenal (HPA)-axis reactivity. However, in humans, experimental paradigms investigating long-term exposure to sex hormones are sparse, limiting the understanding of the influence of sex hormones on HPA-axis activity. Gender-affirming hormone therapy (GAHT) in transgender persons enables to study the physiological role of sex steroids partially uncoupled from the distinct genetic background of men and women. METHODS: Ten transwomen (male genotype and female gender identity) and 15 transmen (female genotype and male gender identity) were investigated at baseline and following three months of GAHT by means of the combined dexamethasone (dex)/CRH-test. Linear mixed-effects model analysis was used to assess changes over time and to identify determinants of HPA-axis reactivity. RESULTS: In response to CRH, overall ACTH (+18%) as well as cortisol (+15%) output were increased in transwomen after 3-months of estrogen and antiandrogen treatment, while the opposite was the case for transmen after testosterone treatment (-15% and -58%, respectively). The ACTH/Cortisol-ratio indicated that testosterone attenuated sensitivity for ACTH at the adrenal level in transmen. Interestingly, copeptin levels before CRH administration were a strong predictor of overall cortisol secretion. CONCLUSIONS: This is the first study demonstrating long-term effects of a complete reversal of the sex-hormonal milieu on HPA-axis activity in humans. Our findings hereby expand the current knowledge of the physiology of HPA-axis regulation. and may be particularly relevant for transgender and cisgender people undergoing hormonal suppression or substitution therapies.

Clinical score system in the treatment of Cushing's disease: failure to identify discriminative variables from the German Cushing's Registry.

PURPOSE: To develop a multidimensional and integrated clinical scoring instrument, that encompasses, summarizes and weights appropriately the desired clinical benefits of a treatment for Cushing's disease (CD). METHODS: A panel of 42 variables potentially relevant to the clinical course of CD was predefined by endocrinology experts taking into account relevant literature. Variables as well as biochemical disease activity assessed as urinary free cortisol (UFC) levels were evaluated at baseline and at least after 12 months in patients treated between 2012 and 2016 in two Munich-based academic centres of the German Cushing's Registry. The primary endpoint was the identification of variables whose changes from baseline to follow-up visit(s) could characterize well biochemical cured from not cured patients after 12 months. RESULTS: Ninety nine patients with at least two consecutive visits were enrolled. Biochemical data were available for 138 visit-pairs among which UFC was not controlled in 48 (34.8%) and controlled in 90 (65.2%) first visits. In 41 (29.7%) consecutive visits (visit-pairs) changes in biochemical activity categories was observed between visits; concretely: in 17 (12.3%) consecutive visits changing from previously controlled to not controlled, and in 24 (17.4%) from uncontrolled to controlled biochemical activity. Multivariate statistical analyses (especially analyses of variance) based on data of the 138 visit-pairs were performed in order to proof possible effects of biochemical activity on clinical benefits. However, in none of the considered 42 variables corresponding to quality of life-dimensions, laboratory, anthropometric, musculo-skeletal or other clinical areas any statistically significant differences between different categories of biochemical activity were observed. CONCLUSION: It was not possible to provide clinical key parameters in our population of patients with CD discriminating biochemical cured from non-cured patients and to construct a clinical scoring system reflecting clinical treatment benefits.

"The Adrenal Gland: Central Relay in Health and Disease - Current Challenges and Perspectives 2018" - Cushing's Disease.

BACKGROUND: Despite advances in diagnostic and therapeutic approach, Cushing's disease (CD) presents a challenging situation for the treating physician. AIMS: To elucidate current challenges, present strengths and pitfalls of existing diagnostic tests, enlighten the need for new diagnostic approaches, appraise the effects of surgery and available pharmacological agents and identify future perspectives regarding CD. MATERIALS AND METHODS: Systematic search to PubMed and Medline databases for publications mainly over the last five years. RESULTS: Mutations in the ubiquitin specific peptidase 8 gene have been recently identified in functional sporadic corticotroph adenomas causing CD. Since the prevalence of obesity and metabolic syndrome is rapidly increasing, new diagnostic tests are necessary to differentiate these conditions. Next to the traditional tests, a cutoff of preoperative ACTH/cortisol ratio, an ultrasensitive late night salivary cortisol assay and the desmopressin test have been suggested as valid tools for the diagnosis and differential diagnosis of CD. Transsphenoidal surgery with variable remission and recurrence rates presents the treatment of choice for CD. Medical therapy consists of adrenal-targeted drugs e. g. ketoconazole, metyrapone, etomidate and mitotane and pituitary-targeted drugs e. g. pasireotide, cabergoline and retinoic acid. CONCLUSIONS: CD is associated to a significant clinical burden, since numerous comorbidities persist after long-term biochemical control. These chronically ill patients show an increased mortality despite disease remission. Clinicians should treat comorbidities aggressively and seek for appropriate consultations. Structured consultation hours and expert excellence networks are needed in order to allow optimal, individualized care for affected patients, reverse increased morbidity and mortality and identify tumor recurrence early.

Shorter telomeres associated with high doses of glucocorticoids: the link to increased mortality?

OBJECTIVE: Patients with non-functioning pituitary adenomas exhibit high morbidity and mortality rates. Growth hormone deficiency and high doses of glucocorticoid substitution therapy have been identified as corresponding risk factors. Interestingly, high levels of endogenous cortisol in, e.g., patients with post-traumatic stress disorder or patients with Cushing's disease have been linked to shorter telomere length. Telomeres are noncoding DNA regions located at the end of chromosomes consisting of repetitive DNA sequences which shorten with ageing and hereby determine cell survival. Therefore, telomere length can serve as a predictor for the onset of disease and mortality in some endocrine disorders (e.g., Cushing's disease). DESIGN/METHODS: We examine telomere length from blood in patients (n = 115) with non-functioning pituitary adenomas (NFPA) in a cross-sectional case control (n = 106, age-, gender- matched) study using qPCR. Linear regression models were used to identify independent predictors of telomere length. RESULTS: We show that patients with NFPA exhibited shorter telomeres than controls. No significant association of indices of growth hormone deficiency (IGF-1-level-SDS, years of unsubstituted growth hormone deficiency etc.) with telomere length was detected. Interestingly, linear regression analysis showed that hydrocortisone replacement dosage in patients with adrenal insufficiency (n = 52) was a significant predictor for shorter telomere length (ß = 0.377; p = 0.018) independent of potential confounders. Median split analysis revealed that higher hydrocortisone intake (> 20 mg) was associated with significantly shorter telomeres. CONCLUSION: These observations strengthen the importance of adjusted glucocorticoid treatment in NFPA patients with respect to morbidity and mortality rates.

Recent advances in understanding corticotroph pituitary tumor initiation and progression.

Cushing's disease is the most frequent form of hypercortisolism and is caused by hypophyseal corticotroph adenomas secreting excessive amounts of adrenocorticotropic hormone. Most of the tumors develop sporadically and only a limited number of corticotroph adenomas have been found to be associated with different neuroendocrine syndromes or with familial isolated pituitary adenomas. The pathogenic mechanisms of corticotroph adenomas are largely unknown, but the discovered aberrant chaperoning activity of heat shock protein 90 on the one hand and the presence of ubiquitin-specific protease 8 mutations on the other hand partially explained the causes of their development. Corticotroph tumors arise initially as benign microadenomas but with time form invasively growing aggressive macroadenomas which can switch to corticotroph carcinomas in extremely rare cases. The mechanisms through which corticotroph tumors escape from glucocorticoid negative feedback are still poorly understood, as are the processes that trigger the progression of benign corticotroph adenomas toward aggressive and malignant phenotypes. This review summarizes recent findings regarding initiation and progression of corticotroph pituitary tumors.

The USP8 mutational status may predict long-term remission in patients with Cushing's disease.

OBJECTIVE: Almost half of the cases of Cushing's disease (CD) tumours carry recurrent activating somatic mutations in the ubiquitin-specific protease eight gene (USP8). The USP8 mutational status could predict remission in patients with CD, so our objective was to correlate the presence of somatic USP8 mutations with the rate of recurrence after transsphenoidal surgery (TSS) retrospectively. DESIGN: Biochemical, radiological and clinical data were retrospectively assessed in 48 patients. USP8 mutational status was determined from corticotroph tumour samples. Association between USP8 mutational status, remission and recurrence was investigated. PATIENTS: Patients with Cushing's disease from a single-centre cohort who underwent TSS between 1991 and 2012. MEASUREMENTS: Long-term remission and recurrence rate after TSS with at least 6 months follow-up. Biochemical, radiological and clinical data, including sex, age at diagnosis, tumour size and pre-operative hormonal levels. USP8 mutational status. RESULTS: Patients with USP8 mutant corticotroph tumours (18 of 48; 37%) were diagnosed significantly earlier (mean ± SD 46 ± 10 years vs 53 ± 11 years; P = 0.028) and presented with higher pre-operative 24-hour urinary-free cortisol levels (median IQR µg/24 hours 1174.0, 1184.5 vs 480.0, 405.3; P = 0.045). The incidence of recurrence in a 10-year follow-up was significantly higher in patients with USP8 mutant tumours after the initial remission (58% vs 18% P = 0.026). Recurrence appeared significantly earlier in these patients (months 70, 44-97 95% CI vs 102, 86-119 95% CI; P = 0.019). CONCLUSION: Recurrence appears to be more frequent and earlier after TSS in patients with USP8 mutant corticotroph tumours.