Appetite-regulating hormone changes in patients with craniopharyngioma

Acquired hypothalamic obesity: A clinical overview and update

Hypothalamic obesity (HO) is a rare and complex disorder that confers substantial morbidity and excess mortality. HO is a unique subtype of obesity characterized by impairment in the key brain pathways that regulate energy intake and expenditure, autonomic nervous system function, and peripheral hormonal signalling. HO often occurs in the context of hypothalamic syndrome, a constellation of symptoms that follow from disruption of hypothalamic functions, for example, temperature regulation, sleep-wake circadian control, and energy balance. Genetic forms of HO, including the monogenic obesity syndromes, often impact central leptin-melanocortin pathways. Acquired forms of HO occur as a result of tumours impacting the hypothalamus, such as craniopharyngioma, surgery or radiation to treat those tumours, or other forms of hypothalamic damage, such as brain injury impacting the region. Risk for severe obesity following hypothalamic injury is increased with larger extent of hypothalamic damage or lesions that contain the medial and posterior hypothalamic nuclei that support melanocortin signalling pathways. Structural damage in these hypothalamic nuclei often leads to hyperphagia, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue, the collective effect of which is rapid weight gain. Individuals with hyperphagia are perpetually hungry. They do not experience fullness at the end of a meal, nor do they feel satiated after meals, leading them to consume larger and more frequent meals. To date, most efforts to treat HO have been disappointing and met with limited, if any, long-term success. However, new treatments based on the distinct pathophysiology of disturbed energy homeostasis in acquired HO may hold promise for the future.

Treatment of hypothalamic obesity in people with hypothalamic injury: new drugs are on the horizon

Hypothalamic obesity (HO) is a complex and rare disorder affecting multiple regulatory pathways of energy intake and expenditure in the brain as well as the regulation of the autonomic nervous system and peripheral hormonal signaling. It can be related to monogenic obesity syndromes which often affect the central leptin-melanocortin pathways or due to injury of the hypothalamus from pituitary and hypothalamic tumors, such as craniopharyngioma, surgery, trauma, or radiation to the hypothalamus. Traditional treatments of obesity, such as lifestyle intervention and specific diets, are still a therapeutic cornerstone, but often fail to result in meaningful and sustained reduction of body mass index. This review will give an update on pharmacotherapies of HO related to hypothalamic injury. Recent obesity drug developments are promising for successful obesity intervention outcomes.

Evaluating Eating Behaviour, Energy Homeostasis, and Obesity in Childhood-Onset Craniopharyngioma: A Feasibility Study

INTRODUCTION

Craniopharyngiomas are rare brain tumours (incidence 1.1-1.7 cases/million/year). Although non-malignant, craniopharyngioma causes major endocrine and visual morbidities including hypothalamic obesity, yet mechanisms leading to obesity are poorly understood. This study investigated the feasibility and acceptability of eating behaviour measures in patients with craniopharyngioma to inform the design of future trials.

METHODS

Patients with childhood-onset craniopharyngioma and controls matched for sex, pubertal stage, and age were recruited. After an overnight fast, participants received the following measures: body composition, resting metabolic rate, oral glucose tolerance test including magnetic resonance imaging (patients only), appetite ratings, eating behaviour, and quality of life questionnaires, ad libitum lunch, and an acceptability questionnaire. Data are reported as median ± IQR, with effect size measure (Cliff's delta) and Kendall's tau for correlations, due to the small sample size.

RESULTS

Eleven patients (median age = 14 years; 5 F/6 M) and matched controls (median age = 12 years; 5 F/6 M) were recruited. All patients had received surgery, and 9/11 also received radiotherapy. Hypothalamic damage post-surgery was graded (Paris grading): grade 2 n = 6; grade 1 n = 1; grade 0 n = 2. The included measures were deemed highly tolerable by participants and their parent/carers. Preliminary data suggest a difference in hyperphagia between patients and controls (d = 0.5), and a relationship between hyperphagia with body mass index standard deviation score (BMISDS) in patients (τ = 0.46).

DISCUSSION

These findings demonstrate that eating behaviour research is feasible and acceptable to craniopharyngioma patients and there is an association between BMISDS and hyperphagia in patients. Thus, food approach and avoidance behaviours may be useful targets for interventions to manage obesity in this patient group.

Craniopharyngioma in Pediatrics and Adults

Craniopharyngiomas are rare malignancies of dysembryogenic origin, involving the sellar and parasellar areas. These low-grade, epithelial tumors account for two main histological patterns (adamantinomatous craniopharyngioma and papillary craniopharyngioma), which differ in epidemiology, pathogenesis, and histomorphological appearance. Adamantinomatous craniopharyngiomas typically show a bimodal age distribution (5-15 years and 45-60 years), while papillary craniopharyngiomas are limited to adult patients, especially in the fifth and sixth decades of life. Recently, craniopharyngioma histological subtypes have been demonstrated to harbor distinct biomolecular signatures. Somatic mutations in CTNNB1 gene encoding β-catenin have been exclusively detected in adamantinomatous craniopharyngiomas, which predominantly manifest as cystic lesions, while papillary craniopharyngiomas are driven by BRAF V600E mutations in up to 95% of cases and are typically solid masses. Despite the benign histological nature (grade I according to the World Health Organization classification), craniopharyngiomas may heavily affect long-term survival and quality of life, due to their growth pattern in a critical region for the presence of eloquent neurovascular structures and possible neurological sequelae following their treatment. Clinical manifestations are mostly related to the involvement of hypothalamic-pituitary axis, optic pathways, ventricular system, and major blood vessels of the circle of Willis. Symptoms and signs referable to intracranial hypertension, visual disturbance, and endocrine deficiencies should promptly raise the clinical suspicion for sellar and suprasellar pathologies, advocating further neuroimaging investigations, especially brain MRI. The optimal therapeutic management of craniopharyngiomas is still a matter of debate. Over the last decades, the surgical strategy for craniopharyngiomas, especially in younger patients, has shifted from the aggressive attempt of radical resection to a more conservative and individualized approach via a planned subtotal resection followed by adjuvant radiotherapy, aimed at preserving functional outcomes and minimizing surgery-related morbidity. Whenever gross total removal is not safely feasible, adjuvant radiotherapy (RT) and stereotactic radiosurgery (SRS) have gained an increasingly important role to manage tumor residual or recurrence. The role of intracavitary therapies, including antineoplastic drugs or sealed radioactive sources, is predominantly limited to monocystic craniopharyngiomas as secondary therapeutic option. Novel findings in genetic profiling of craniopharyngiomas have unfold new scenarios in the development of targeted therapies based on brand-new biomolecular markers, advancing the hypothesis of introducing neoadjuvant chemotherapy regimens in order to reduce tumor burden prior to resection. Indeed, the rarity of these neoplasms requires a multispecialty approach involving an expert team of endocrinologists, neurosurgeons, neuro-ophthalmologists, neuroradiologists, radiotherapists, and neuro-oncologists, in order to pursue a significant impact on postoperative outcomes and long-term prognosis.

A temperature-regulated circuit for feeding behavior

Both rodents and primates have evolved to orchestrate food intake to maintain thermal homeostasis in coping with ambient temperature challenges. However, the mechanisms underlying temperature-coordinated feeding behavior are rarely reported. Here we find that a non-canonical feeding center, the anteroventral and periventricular portions of medial preoptic area (apMPOA) respond to altered dietary states in mice. Two neighboring but distinct neuronal populations in apMPOA mediate feeding behavior by receiving anatomical inputs from external and dorsal subnuclei of lateral parabrachial nucleus. While both populations are glutamatergic, the arcuate nucleus-projecting neurons in apMPOA can sense low temperature and promote food intake. The other type, the paraventricular hypothalamic nucleus (PVH)-projecting neurons in apMPOA are primarily sensitive to high temperature and suppress food intake. Caspase ablation or chemogenetic inhibition of the apMPOA→PVH pathway can eliminate the temperature dependence of feeding. Further projection-specific RNA sequencing and fluorescence in situ hybridization identify that the two neuronal populations are molecularly marked by galanin receptor and apelin receptor. These findings reveal unrecognized cell populations and circuits of apMPOA that orchestrates feeding behavior against thermal challenges.

Postoperative hypothalamic damage predicts postoperative weight gain in patients with adult-onset craniopharyngioma

OBJECTIVE

This study aimed to recapitulate the change trajectory of postoperative weight and investigate the association between postoperative hypothalamic damage and weight gain and hypothalamic obesity (HO) in patients with adult-onset craniopharyngioma.

METHODS

The data of 96 patients with surgically treated primary adult-onset craniopharyngioma were retrospectively analyzed. The association between postoperative hypothalamic damage based on magnetic resonance images or endoscopic observation and postoperative weight gain and HO was determined by multivariable logistic regression.

RESULTS

Forty-seven (49.0%) patients and 18 (18.8%) patients experienced clinically meaningful weight gain (≥5%) and HO at last follow-up, respectively. Postoperative weight significantly increased during the first 6 months following surgery, followed by stabilization. Both grade 2 postoperative hypothalamus damage, as evaluated by the magnetic resonance imaging classification system of Müller et al., and higher scores based on the Roth et al. hypothalamic lesion score were significantly associated with postoperative weight gain of ≥5% (p = 0.005 and p = 0.002) and with HO (p = 0.001 and p = 0.008). Additionally, bilateral hypothalamic injury as evaluated by the Hong et al. hypothalamic injury pattern based on endoscopic observation (p = 0.008) could predict postoperative weight gain ≥5%.

CONCLUSIONS

Significant postoperative weight gain is common in patients with adult-onset craniopharyngioma. Postoperative hypothalamic damage can predict clinically meaningful weight gain and HO.

Hypothalamic syndrome

Hypothalamic syndrome (HS) is a rare disorder caused by disease-related and/or treatment-related injury to the hypothalamus, most commonly associated with rare, non-cancerous parasellar masses, such as craniopharyngiomas, germ cell tumours, gliomas, cysts of Rathke's pouch and Langerhans cell histiocytosis, as well as with genetic neurodevelopmental syndromes, such as Prader-Willi syndrome and septo-optic dysplasia. HS is characterized by intractable weight gain associated with severe morbid obesity, multiple endocrine abnormalities and memory impairment, attention deficit and reduced impulse control as well as increased risk of cardiovascular and metabolic disorders. Currently, there is no cure for this condition but treatments for general obesity are often used in patients with HS, including surgery, medication and counselling. However, these are mostly ineffective and no medications that are specifically approved for the treatment of HS are available. Specific challenges in HS are because the syndrome represents an adverse effect of different diseases, and that diagnostic criteria, aetiology, pathogenesis and management of HS are not completely defined.

Craniopharyngiomas

Craniopharyngiomas are rare epithelial tumours situated primarily in the sellar/parasellar region, occurring along the path of the craniopharyngeal duct. Whilst classed as histologically benign tumours, their unpredictable growth pattern and proximity to vital structures including the optic chiasm, hypothalamus, and pituitary gland renders them a considerable threat, with significant associated morbidity and increase in mortality. Occurring both in child and adulthood, their clinical manifestations are broad, commonly with symptoms/signs secondary to hypothalamic-pituitary dysfunction, raised intracranial pressure and visual compromise. They have two distinct histological subtypes (adamantinomatous and papillary), with unique patterns of age distribution, and genetic and molecular make-up. With increasing understanding of their genetic pathogenesis including BRAF V600E mutations in the papillary subtype, and β-catenin mutations in the adamantinomatous, further research provides hope for the discovery of targeted medical therapy that can exploit molecular changes occurring as a result of such alterations. Until then, primary treatment consists of surgery with or without radiotherapy, with intracystic aspiration, chemotherapy or irradiation being alternative options in selected patients. Long term management by an experienced multidisciplinary team is essential, given the breadth of complications, including hypothalamic morbidity, visual compromise, cognitive and neuropsychological sequelae and impairment to quality of life.

Childhood-onset Craniopharyngioma

Craniopharyngiomas are rare embryonic malformational tumors of the sellar/parasellar region, classified by the World Health Organization (WHO) as tumors with low-grade malignancy (WHO I). The childhood adamantinomatous subtype of craniopharyngioma is usually cystic with calcified areas. At the time of diagnosis, hypothalamic/pituitary deficits, visual disturbances, and increased intracranial pressure are major symptoms. The treatment of choice in case of favorable tumor location (without hypothalamic involvement) is complete resection. It is important to ensure that optical and hypothalamic functionality are preserved. In case of unfavorable tumor location, that is with hypothalamic involvement, a hypothalamus-sparing surgical strategy with subsequent local irradiation of residual tumor is recommended. In the further course of the disease, recurrences and progression often occur. Nevertheless, overall survival rates are high at 92%. Severe impairment of quality of life and comorbidities such as metabolic syndrome, hypothalamic obesity, and neurological consequences can be observed in patients with disease- and/or treatment-related lesions of hypothalamic structures. Childhood-onset craniopharyngioma frequently manifests as a chronic disease so that patients require lifelong, continuous care by experienced multidisciplinary teams to manage clinical and quality of life consequences. For this review, a search for original articles and reviews published between 1986 and 2020 was performed in Pubmed, Science Citation Index Expanded, EMBASE, and Scopus. The search terms used were "craniopharyngioma, hypothalamus, pituitary obesity, irradiation, neurosurgery.

Appetite- and weight-inducing and -inhibiting neuroendocrine factors in Prader-Willi syndrome, Bardet-Biedl syndrome and craniopharyngioma versus anorexia nervosa

Obesity is reaching an epidemic state and has a major impact on health and economy. In most cases, obesity is caused by lifestyle factors. However, the risk of becoming obese differs highly between people. Individual's differences in lifestyle, genetic, and neuroendocrine factors play a role in satiety, hunger and regulation of body weight. In a small percentage of children and adults with obesity, an underlying hormonal or genetic cause can be found. The aim of this review is to present and compare data on the extreme ends of the obesity and undernutrition spectrum in patients with Prader-Willi syndrome (PWS), Bardet-Biedl syndrome (BBS), acquired hypothalamic obesity in craniopharyngioma patients, and anorexia nervosa. This may give more insight into the role of neuroendocrine factors and might give direction for future research in conditions of severe obesity and underweight.

Preoperative BMI Predicts Postoperative Weight Gain in Adult-onset Craniopharyngioma

CONTEXT

Craniopharyngiomas, while benign, have the highest morbidity of all nonmalignant sellar tumors. Studies on weight and metabolic outcomes in adult-onset craniopharyngioma (AOCP) remain sparse.

OBJECTIVE

To examine postsurgical weight and metabolic outcomes in AOCP and to identify any clinical predictors of weight gain.

METHODS

Retrospective chart review of patients with AOCP who underwent surgery between January 2014 and May 2019 in a single pituitary center. The study included 45 patients with AOCP with a minimum follow-up of 3 months. Median follow-up time was 26 months (interquartile range [IQR] 10-44). Main outcome measures were the changes in weight/body mass index (BMI), metabolic comorbidities, and pituitary deficiencies between preoperative and last follow-up.

RESULTS

Both weight and BMI were higher at last follow-up, with a mean increase of 3.4 kg for weight (P = .015) and 1.15 kg/m2 for BMI (P = .0095). Median % weight change was 2.7% (IQR -1.1%, 8.8%). Obesity rate increased from 37.8% at baseline to 55.6% at last follow-up. One-third of patients had ~15% median weight gain. The prevalence of metabolic comorbidities at last follow-up was not different from baseline. Pituitary deficiencies increased postoperatively, with 58% of patients having ≥3 hormonal deficiencies. Preoperative BMI was inversely associated with postoperative weight gain, which remained significant after adjusting for age, sex, race, tumor, and treatment characteristics. Patients with ≥3 hormonal deficiencies at last follow-up also had higher postoperative weight gain.

CONCLUSION

In this AOCP cohort, those with a lower BMI at the preoperative visit had higher postoperative weight gain. Our finding may help physicians better counsel patients and provide anticipatory guidance on postoperative expectations and management.

Craniopharyngiomas primarily affecting the hypothalamus

The concept of craniopharyngiomas (CPs) primarily affecting the hypothalamus, or "hypothalamic CPs" (Hy-CPs), refers, in a restrictive sense, to the subgroup of CPs originally developing within the neural tissue of the infundibulum and tuber cinereum, the components of the third ventricle floor. This subgroup, also known as infundibulo-tuberal CPs, largely occupies the third ventricle and comprises up to 40% of this pathological entity. The small subgroup of strictly intraventricular CPs (5%), lesions wholly developed within the third ventricle above an anatomically intact third ventricle floor, can also be included within the Hy-CP category. The remaining types of sellar and/or suprasellar CPs may compress or invade the hypothalamic region during their growth but will not be considered in this review. Hy-CPs predominantly affect adults, causing a wide range of symptoms derived from hypothalamic dysfunction, such as adiposogenital dystrophy (Babinski-Fröhlich's syndrome), diabetes insipidus (DI), abnormal diurnal somnolence, and a complex set of cognitive (dementia-like, Korsakoff-like), emotional (rage, apathy, depression), and behavioral (autism-like, psychotic-like) disturbances. Accordingly, Hy-CPs represent a neurobiological model of psychiatric disorders caused by a lesion restricted to the hypothalamus. The vast majority (90%) of squamous-papillary CPs belong to the Hy-CP category. Pathologically, most Hy-CPs present extensive and strong adhesions to the surrounding hypothalamus, usually formed of a thick band of gliotic tissue encircling the central portion of the tumor ("ring-like" attachment) or its entire boundary ("circumferential" attachment). CPs with these severe adhesion types associate high surgical risk, with morbidity and mortality rates three times higher than those for sellar/suprasellar CPs. Consequently, radical surgical removal of Hy-CPs cannot be generally recommended. Rather, Hy-CPs should be accurately classified according to an individualized surgery-risk stratification scheme considering patient age, CP topography, presence of hypothalamic symptoms, tumor size, and, most importantly, the CP-hypothalamus adhesion pattern.

Management of Hypothalamic Obesity

Energy homeostasis, appetite, and satiety are modulated by a complex neuroendocrine system regulated by the hypothalamus. Dysregulation of this system resulting in hypothalamic obesity (HO) is caused by brain tumors, neurosurgery, and/or cranial irradiation. Craniopharyngioma (CP) is a paradigmatic disease with regard to the development of HO. Initial hypothalamic involvement of CP and/or treatment-related damage to hypothalamic-pituitary axes result in HO. Attempts to control HO with lifestyle interventions have not been satisfactory. No generally accepted pharmacologic or bariatric therapy for HO in CP has been effective in randomized controlled trials. Accordingly, prevention of HO is recommended.

Craniopharyngioma treatment: an updated summary of important clinicopathological concepts

INTRODUCTION

Craniopharyngiomas (CPs) are benign histological tumors that may develop at different positions along the hypothalamic-pituitary axis. Their close, heterogenous relationship to the hypothalamus makes surgical removal challenging even though this remains the primary treatment strategy.

AREAS COVERED

This article presents a critical overview of the pathological and clinical concepts regarding CPs that should be considered when planning treatment. Thus, we have performed a comprehensive review of detailed CP reports published between 1839 and 2020.

EXPERT OPINION

CP surgery should pursue maximal tumor resection while minimizing the risk of injuring the hypothalamus. Therefore, surgical strategies should be individualized for each patient. Accurate assessment of presenting symptoms and preoperative MRI has proven useful to predict the type of CP-hypothalamus relationship that will be found during surgery. CPs with dense and extensive adhesions to the hypothalamus should be highly suspected when MRI shows the hypothalamus positioned around the mid-third of the tumor and an amputated upper portion of the pituitary stalk. Symptoms related to functional impairment of the infundibulo-tuberal area of the third ventricle floor, such as obesity/hyperphagia, Fröhlich's syndrome, diabetes insipidus, and/or somnolence, also indicate risky CP-hypothalamic adhesions. In these cases, limited tumor removal is strongly advocated followed by radiation therapy.

Metabolic features and changes in glucose-induced serum glucagon-like peptide-1 levels in children with hypothalamic obesity

Background Hypothalamic damage may alter glucagon-like peptide-1 (GLP-1) secretion and be involved in the pathogenesis of obesity. We aim to evaluate the metabolic features and the dynamic changes of GLP-1 levels during an oral glucose tolerance test (OGTT) in children with hypothalamic obesity (HO) compared with simple obesity controls. Methods Subjects included eight patients (six females, aged 9-16 years) with hypothalamo-pituitary tumors who later developed obesity and eight controls with simple obesity matched for age, body mass index (BMI), gender and puberty. We assessed the metabolic syndrome features, fat mass, severity of hyperphagia using a standardized questionnaire, and measured glucose, insulin and GLP-1 levels during a standard 75 g OGTT. Results Age, gender distribution, pubertal status and BMI-Z scores were not significantly different. Subjects with HO had higher fasting triglycerides (TG) than controls (128 vs. 94 mg/dL; p=0.05). Four HO subjects and three controls met the criteria for the metabolic syndrome. Fasting and 120 min post-glucose load GLP-1 levels were significantly higher in HO patients than in controls (21.9 vs. 19.7 pg/mL; p=0.025, 22.1 vs. 17.7 pg/mL; p=0.012). Patients with HO had significantly higher hyperphagia scores than in simple obese controls (13 vs. 2.5; p=0.012). Conclusions Patients with HO appear to have more metabolic complications and hyperphagia than controls with simple obesity. Impaired satiety may play an important role in HO. Fasting and glucose-induced serum GLP-1 concentrations seem to be altered in HO patients and could be a part of the pathogenesis of HO.

Hypothalamic Obesity: Prologue and Promise

Hypothalamic obesity (HO) frequently occurs following damage to the medial hypothalamic region, encompassing the arcuate nucleus, the paraventricular nucleus, the ventromedial nucleus, the dorsomedial nucleus, and the dorsal hypothalamic area, which are critically involved in the regulation of satiety and energy balance through neural and humoral connections. HO is most commonly described in the context of craniopharyngioma and its treatment, but it can also occur following other suprasellar tumors, radiation, trauma, or a surgical insult to the hypothalamus. A constellation of loss of satiety and a reduction of the metabolic rate, thermogenesis, and physical activity as well as increased vagal tone and hyperinsulinism with insulin and leptin resistance results in rapid weight gain due to a decreased energy expenditure and increased energy storage in adipose cells. To date, no viable long-term solution for HO has been found, due either to the requirement of intact hypothalamic pathways or to significant side effects. Newer therapeutic modalities focused on the unique pathophysiology of this condition offer potential for successful treatment. In this review, we describe the etiology of HO as well as past/current treatment approaches in the categories of hyperinsulinism, surgical approaches, and targeting energy expenditure/anorectic drugs. We conclude by providing an overview of the clinical trials currently underway.

Craniopharyngioma

Craniopharyngiomas are rare malformational tumours of low histological malignancy arising along the craniopharyngeal duct. The two histological subtypes, adamantinomatous craniopharyngioma (ACP) and papillary craniopharyngioma (PCP), differ in genesis and age distribution. ACPs are diagnosed with a bimodal peak of incidence (5-15 years and 45-60 years), whereas PCPs are restricted to adults mainly in the fifth and sixth decades of life. ACPs are driven by somatic mutations in CTNNB1 (encoding β-catenin) that affect β-catenin stability and are predominantly cystic in appearance. PCPs frequently harbour somatic BRAFV600E mutations and are typically solid tumours. Clinical manifestations due to increased intracranial pressure, visual impairment and endocrine deficiencies should prompt imaging investigations, preferentially MRI. Treatment comprises neurosurgery and radiotherapy; intracystic chemotherapy is used in monocystic ACP. Although long-term survival is high, quality of life and neuropsychological function are frequently impaired due to the close anatomical proximity to the optic chiasm, hypothalamus and pituitary gland. Indeed, hypothalamic involvement and treatment-related hypothalamic lesions frequently result in hypothalamic obesity, physical fatigue and psychosocial deficits. Given the rarity of these tumours, efforts to optimize infrastructure and international collaboration should be research priorities.

Pathophysiology and Individualized Treatment of Hypothalamic Obesity Following Craniopharyngioma and Other Suprasellar Tumors: A Systematic Review

The development of hypothalamic obesity (HO) following craniopharyngioma (CP) and other suprasellar tumors leads to reduced patient quality of life. No treatment algorithms are currently available for management of HO. Depending on which hypothalamic nuclei are destroyed, the pathophysiologic mechanisms and clinical symptoms that contribute to HO differ among patients. Herein, we review the contribution of the hypothalamus to the pathophysiologic mechanisms and symptoms underlying CP-associated HO. Additionally, we performed a systematic search of MEDLINE and Embase to identify all intervention studies for weight management in patients with CP or other suprasellar tumors published until September 2017. The search yielded 1866 publications, of which 40 were included. Of these 40 studies, we identified four modalities for intervention (i.e., lifestyle, dietary, pharmacotherapeutic, or surgical) within six clinical domains (i.e., psychosocial disorders, hyperphagia, sleep disturbances, decreased energy expenditure, hyperinsulinemia, and hypopituitarism). We used the findings from our systematic review, in addition to current knowledge on the pathophysiology of HO, to develop an evidence-based treatment algorithm for patients with HO caused by CP or other suprasellar tumors. Although the individual effects of the HO interventions were modest, beneficial individual effects may be achieved when the pathophysiologic background and correct clinical domain are considered. These two aspects can be combined in an individualized treatment algorithm with a stepwise approach for each clinical domain. Recently elucidated targets for HO intervention were also explored to improve future management of HO for patients with CP and other suprasellar tumors.

Detailed assessment of hypothalamic damage in craniopharyngioma patients with obesity

BACKGROUND/OBJECTIVES

Hypothalamic obesity (HO) occurs in 50% of patients with the pituitary tumor craniopharyngioma (CP). Attempts have been made to predict the risk of HO based on hypothalamic (HT) damage on magnetic resonance imaging (MRI), but none have included volumetry. We performed qualitative and quantitative volumetric analyses of HT damage. The results were explored in relation to feeding related peptides and body fat.

SUBJECTS/METHODS

A cross-sectional study of childhood onset CPs involving 3 Tesla MRI, was performed at median 22 years after first operation; 41 CPs, median age 35 (range: 17-56), of whom 23 had HT damage, were compared to 32 controls. After exclusions, 35 patients and 31 controls remained in the MRI study. Main outcome measures were the relation of metabolic parameters to HT volume and qualitative analyses of HT damage.

RESULTS

Metabolic parameters scored persistently very high in vascular risk particularly among HT damaged patients. Patients had smaller HT volumes compared to controls 769 (35-1168) mm³ vs. 879 (775-1086) mm³; P < 0.001. HT volume correlated negatively with fat mass and leptin among CP patients (r_s = -0.67; P < .001; r_s = -0.53; P = 0.001), and explained 39% of the variation in fat mass. For every 100 mm³ increase in HT volume fat mass decreased by 2.7 kg (95% CI: 1.5-3.9; P < 0.001). Qualitative assessments revealed HT damage in three out of six patients with normal volumetry, but HT damage according to operation records.

CONCLUSIONS

A decrease in HT volume was associated with an increase in fat mass and leptin. We present a method with a high inter-rater reliability (0.94) that can be applied by nonradiologists for the assessment of HT damage. The method may be valuable in the risk assessment of diseases involving the HT.

Impact of Age at Diagnosis and Hypothalamic Involvement on Body Mass Index Z-Score Change in Pediatric Brain Tumor Survivors

BACKGROUND

Obesity risk is increased for pediatric central nervous system tumor survivors. Hypothalamic involvement (HI) by tumor or treatment increases the risk. In healthy children, body mass index (BMI) normally declines until adiposity rebound (AR). We hypothesized that HI and diagnosis before AR would lead to increased BMI at follow-up.

METHODS

A chart review of 114 brain tumor survivors diagnosed between 2001-2011 at the Children's Hospital of Wisconsin extracted tumor location, treatment and BMI z-scores at diagnosis and 2-year follow-up. Children were categorized based on age at diagnosis relative to AR and presence/absence of HI.

RESULTS

Children diagnosed pre-AR and post-AR with HI had higher BMI z-scores at 2-year follow-up (pre-AR: 1.6, post-AR: 1.3) than at diagnosis (0.5, 0.6). All groups without HI showed no increase in BMI z-score from diagnosis to 2-year follow-up (pre-AR: 0.7-0.6, during AR: 0.7-0.8, post-AR: 0.7-0.8). The pre-AR and during-AR cohorts with HI had a higher BMI z-score at 2-year follow-up relative to those without HI, while the post-AR group did not.

CONCLUSION

Except for the post-AR group, patients with HI have increased BMI at 2 years after diagnosis compared to those without HI. Diagnosis pre-AR is associated with greater follow-up BMI z-score.

Risk-adapted, long-term management in childhood-onset craniopharyngioma

PURPOSE

This report is a review of findings on the diagnosis, treatment, clinical course, follow-up, and prognosis of craniopharyngioma patients with special regard to clinical trials and long-term management.

METHODS

Literature search on Pubmed for paper published after 1994.

RESULTS

Craniopharyngiomas are rare, embryonic malformations of the sellar/parasellar region with low histological grade. Clinical manifestations are related to increased intracranial pressure, visual impairment, and hypothalamic/pituitary deficiencies. If the tumor is favorably localized, therapy of choice is complete resection, with care taken to preserve hypothalamic and optic functions. In patients with unfavorable tumor location (i.e. involvement of hypothalamic areas), recommended therapy is limited hypothalamus-sparing surgical strategy followed by irradiation. Irradiation has proven effective in treatment of recurrences and progression. Surgical lesions and/or anatomical involvement of posterior hypothalamic areas can result in serious sequelae, mainly hypothalamic syndrome.

CONCLUSIONS

It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' by experienced multidisciplinary teams in the context of multicenter trials.

Postprandial GLP-1 Secretion After Bariatric Surgery in Three Cases of Severe Obesity Related to Craniopharyngiomas

Craniopharyngiomas are rare cerebral tumors associated with severe obesity after hypothalamic surgery. A meta-analysis showed significant weight loss at 1 year after bariatric surgery in these patients even though more modest than in common causes of obesity. We hypothesized that this discrepancy could be partly explained by differences in GLP-1 secretion after surgery since patients with craniopharyngioma present a significantly higher degree of insulin resistance and hyperinsulinism than common obese control. We report three cases of bariatric surgery in patients presenting with hypothalamique obesity related to craniopharyngiomas. At 18 months, the mean weight loss was 20 kg with expected insulin resistance decrease. Before surgery, standardized test meal shows abolition of postprandial GLP-1 secretion in all patients with a progressive restoration in the patients with gastric bypass (GBP) surgery.

Is there an effect of ghrelin/ghrelin analogs on cancer? A systematic review

Ghrelin is a hormone with multiple physiologic functions, including promotion of growth hormone release, stimulation of appetite and regulation of energy homeostasis. Treatment with ghrelin/ghrelin-receptor agonists is a prospective therapy for disease-related cachexia and malnutrition. In vitro studies have shown high expression of ghrelin in cancer tissue, although its role including its impact in cancer risk and progression has not been established. We performed a systematic literature review to identify peer-reviewed human or animal in vivo original research studies of ghrelin, ghrelin-receptor agonists, or ghrelin genetic variants and the risk, presence, or growth of cancer using structured searches in PubMed database as well as secondary searches of article reference lists, additional reviews and meta-analyses. Overall, 45 (73.8%) of the 61 studies reviewed, including all 11 involving exogenous ghrelin/ghrelin-receptor agonist treatment, reported either a null (no statistically significant difference) or inverse association of ghrelin/ghrelin-receptor agonists or ghrelin genetic variants with cancer risk, presence or growth; 10 (16.7%) studies reported positive associations; and 6 (10.0%) reported both negative or null and positive associations. Differences in serum ghrelin levels in cancer cases vs controls (typically lower) were reported for some but not all cancers. The majority of in vivo studies showed a null or inverse association of ghrelin with risk and progression of most cancers, suggesting that ghrelin/ghrelin-receptor agonist treatment may have a favorable safety profile to use for cancer cachexia. Additional large-scale prospective clinical trials as well as basic bioscientific research are warranted to further evaluate the safety and benefits of ghrelin treatment in patients with cancer.

A 52-week pilot study of the effects of exenatide on body weight in patients with hypothalamic obesity

OBJECTIVE

Hypothalamic obesity (HO) is a common complication of hypothalamic tumors, and effective therapies are lacking. The objective of this pilot study was to investigate changes in body weight before and during treatment with exenatide.

METHODS

This was a prospective, open-label, 52-week pilot study of exenatide (10 mcg b.i.d.) in adults with HO. Ten patients enrolled, and eight completed the study. Study measures included indirect calorimetry, body composition, buffet meals, diet recall, actigraphy, and hormone assays.

RESULTS

Participants had obesity with a baseline weight of 137.2 ± 37.6 kg. Exenatide therapy was well tolerated. Change in weight with exenatide therapy was not significant (-1.4 ± 4.3 kg [95% CI -4.9 to 2.2], P = 0.40), but six out of eight completers lost weight (-6.2 to -0.2 kg). Participants reported significantly lower intake on food recall during treatment compared with baseline (7837.8 ± 2796.6 vs. 6258.4 ± 1970.7 kJ [95% CI -2915.8 to -242.6], P = 0.027), but there was no change in intake during buffet meals.

CONCLUSIONS

Significant weight loss was not observed in patients with HO treated with exenatide, but 75% of completers had stable or decreasing weight. Further studies are needed to evaluate weight loss efficacy in patients with HO.

Activation of nuclear factor kappa B pathway and reduction of hypothalamic oxytocin following hypothalamic lesions

Background

Hypothalamic obesity (HO) occurs in patients with tumors and lesions in the medial hypothalamic region. In this study, a hyperphagic rat model of combined medial hypothalamic lesions (CMHL) was used to test which specific inflammatory molecules are involved.

Methods

In order to target specific homeostatic medial hypothalamic nuclei (arcuate, ventromedial, and dorsomedial nuclei), male Sprague-Dawley rats (age of 8 weeks, ~250 g body weight) received four electrolytic lesions or sham surgery. Post-surgery food intake and weight changes were tracked and hypothalamic gene expression for inflammatory molecules as well as anorexigenic peptide oxytocin 7 days and 7 months post-surgery were tested.

Results

Seven days post-surgery, average food intake increased by 23%, and body weight gain had increased by 68%. Toll-like 4 receptor/nuclear factor–κB (TLR4/NF–κB)—pathway was specifically activated in the mediobasal hypothalamus (MBH), resulting in 3-fold higher tumor necrosis factor (TNF)-α, 10-fold higher interleukin (IL) 1-β mRNA levels, and higher expression of suppression of cytokine signaling (SOCS) 3, while oxytocin mRNA levels were significantly reduced in CMHL rats versus sham surgery rats 7 days post-surgery. At 7 months, inflammation was less stimulated in MBH of CMHL rats compared to 7 days post-surgery and SOCS 3 as well as oxytocin mRNA levels were comparable between the two groups.

Conclusion

Medial hypothalamic lesions are associated with strong post-surgery hyperphagia and activation of TLR4/NF–κB—pathway as well as reduced expression of oxytocin in the hypothalamus.

Nutritional and endocrinologic evaluation of patients with craniopharyngioma

BACKGROUND & AIMS

Lesions of hypothalamus or adjacent brain structures by the craniopharyngioma (CP) and/or its treatment, as well as changes in orexigenic and anorexigenic hormones, are possible pathogenic factors for the obesity observed in CP patients. This study assessed anthropometric measurements, food intake, and biochemical markers of CP patients.

METHODS

Weight, height, skinfold thicknesses, circumferences, body composition, food intake evaluation, basal glucose, lipids, insulin, ghrelin, PYY, and HOMA-IR calculation were obtained from CP children (n = 10, 4F, aged 12 ± 4.2yr) and CP adults (n = 27,13F aged 42 ± 13 yr) and from 32 gender and age matched controls.

RESULTS

Overweight/obesity was observed in 51.4% of the patients at the diagnosis and increased to 86.5% at the time of the study. Obesity was more frequent in patients with grade 2 hypothalamic involvement. Most anthropometric measurements were similar in patients and controls. Caloric intake was lower in CP adults, without difference between children. Lipid intake was higher in CP patients. Carbohydrate and protein intakes were lower in CP children, with no difference between adult groups. There were no differences in micronutrients intake as well as in insulin and PYY levels, and HOMA-IR between patients and controls. HDL-c was lower in CP adults and ghrelin higher in CP children.

CONCLUSIONS

There is a high rate of overweight/obesity in CP patients at the diagnosis and throughout the follow-up period. Obesity was associated with degree of hypothalamic involvement but not with caloric intake. Obesity and a lipid rich diet may have contributed to the dyslipidemia observed in CP patients.

Hypothalamic Obesity in Craniopharyngioma Patients: Disturbed Energy Homeostasis Related to Extent of Hypothalamic Damage and Its Implication for Obesity Intervention

Hypothalamic obesity (HO) occurs in patients with tumors and lesions in the medial hypothalamic region. Hypothalamic dysfunction can lead to hyperinsulinemia and leptin resistance. This review is focused on HO caused by craniopharyngiomas (CP), which are the most common childhood brain tumors of nonglial origin. Despite excellent overall survival rates, CP patients have substantially reduced quality of life because of significant long-term sequelae, notably severe obesity in about 50% of patients, leading to a high rate of cardiovascular mortality. Recent studies reported that both hyperphagia and decreased energy expenditure can contribute to severe obesity in HO patients. Recognized risk factors for severe obesity include large hypothalamic tumors or lesions affecting several medial and posterior hypothalamic nuclei that impact satiety signaling pathways. Structural damage in these nuclei often lead to hyperphagia, rapid weight gain, central insulin and leptin resistance, decreased sympathetic activity, low energy expenditure, and increased energy storage in adipose tissue. To date, most efforts to treat HO have shown disappointing long-term success rates. However, treatments based on the distinct pathophysiology of disturbed energy homeostasis related to CP may offer options for successful interventions in the future.

Semiquantitative analysis of hypothalamic damage on MRI predicts risk for hypothalamic obesity

OBJECTIVE

Excessive weight gain frequently occurs in patients with hypothalamic tumors and lesions leading to hypothalamic obesity (HO).

METHODS

Digital brain magnetic resonance imaging (MRI) and clinical outcomes were studied retrospectively in a single center, including 45 children with postoperative lesions in the sellar region (41 craniopharyngiomas, 4 with Rathke's cleft cysts), ∼5 years post-surgery, mean age 13.9 years. Four standard sections covering hypothalamic areas critical to energy homeostasis were used to assess lesions and calculate a hypothalamic lesion score (HLS); the association with HO was examined.

RESULTS

Compared to subjects who did not develop HO (n = 23), subjects with HO (n = 22) showed more frequently lesions affecting the third ventricular floor, mammillary bodies, and anterior, medial (all P < 0.05), and most importantly posterior hypothalamus (P < 0.01). The HLS correlated significantly with BMI z-score changes 12 and 30 months post-surgery, even after adjusting for potential confounders of gender, age at surgery, surgery date, surgery BMI z-score, hydrocephalus, and residual hypothalamic tumor (r = 0.34, P = 0.03; r = 0.40, P = 0.02, respectively). Diabetes insipidus was found to be an endocrine marker for HO risk.

CONCLUSIONS

The extent of damage following surgery in the sellar region can be assessed by MRI using a novel scoring system for early HO risk assessment.

Neuroendocrine Disorders in Pediatric Craniopharyngioma Patients

Childhood-onset craniopharyngiomas are partly cystic embryonic malformations of the sellar/parasellar region. The therapy of choice in patients with favorable tumor localization is complete resection with a specific focus on maintaining optical and hypothalamic neuroendocrine functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), a limited hypothalamus-sparing surgical strategy followed by local irradiation is recommended. Involvement and/or surgical lesions of posterior hypothalamic areas cause major neuroendocrine sequelae. The overall survival rates are high (92%) but neuroendocrine disorders such as obesity and metabolic syndrome due to involvement and/or treatment-related hypothalamic lesions have major negative impact on survival and quality of life. Recurrences and progressions are frequent post-surgical events. Because irradiation is efficient in preventing tumor progression, appropriate timing of post-surgical irradiation is currently under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Childhood-onset craniopharyngioma should be recognized as a chronic disease requiring treatment and constant monitoring of the clinical and quality of life consequences, frequently impaired due to neuroendocrine disorders, by experienced multidisciplinary teams in order to provide optimal care of surviving patients.

Craniopharyngioma

This report is a review of findings on the diagnosis, treatment, clinical course, and prognosis of craniopharyngioma patients. Craniopharyngiomas are rare, partly cystic and calcified embryonic malformations of the sellar/parasellar region with low histological grade (WHO I°). A bimodal age distribution has been shown, with peak incidence rates in childhood-onset at 5-14 years and adult-onset craniopharyngioma at 50-74 years. Clinical manifestations are related to hypothalamic/pituitary deficiencies, visual impairment, and increased intracranial pressure. If the tumor is favorably localized, the therapy of choice is complete resection, with care taken to preserve optical and hypothalamic functions. In patients with unfavorable tumor localization (i.e., hypothalamic involvement), recommended therapy is a limited hypothalamus-sparing surgical strategy followed by local irradiation. Although overall survival rates are high (92%), recurrences and progressions are frequent. Irradiation has proven effective in reducing recurrences and progression, and timing of postsurgical irradiation in childhood-onset cases is currently under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Anatomical involvement and/or surgical lesions of posterior hypothalamic areas can result in serious quality of life-compromising sequelae such as hypothalamic obesity, psychopathological symptoms, and/or cognitive problems. It is crucial that craniopharyngioma be managed as a frequently chronic disease, providing ongoing care of pediatric and adult patients' clinical and quality of life consequences by experienced multidisciplinary teams.

Food intake regulating hormones in adult craniopharyngioma patients

INTRODUCTION

Patients with craniopharyngioma (CP) have disturbances of the hypothalamic-pituitary axis and serious comorbidities such as obesity. We hypothesized that the secretion of hormones regulating the nutritional status is altered in adult patients with CP compared with patients with non-functioning pituitary adenoma (NFPA).

METHODS

WE INCLUDED 40 CP (50% MALES, MEAN AGE: 49.6±14.3 years) and 40 NFPA (72.5% males, mean age: 63.4±9.8 years) patients. We measured glucose, insulin, leptin, total ghrelin, peptide-YY (PYY) and cholecystokinin (CCK) during oral glucose tolerance test (OGTT). Fat mass (FM) was determined by dual X-ray absorptiometry.

RESULTS

Gender distribution was not significantly different, but CP patients were significantly younger (P<0.001). CP patients had significantly higher BMI and FM than NFPA patients (BMI 32±8 vs 28±4 kg/m(2), P=0.009 and FM 37±9 vs 33±9%, P=0.02). Fasting glucose level (84±12 vs 78±11 mg/dl, P=0.03), leptin (27.9±34.2 vs 11.9±11.6 μg/l, P=0.008) and leptin levels corrected for percentage FM (0.66±0.67 vs 0.32±0.25 μg/l%, P=0.005) were significantly higher in CP than in NFPA patients, whereas ghrelin was significantly lower (131±129 vs 191±119 ng/l, P=0.035). Insulin, PYY and CCK did not differ significantly between groups. After glucose load, leptin decreased significantly in CP patients (P=0.019). In both groups, ghrelin decreased significantly during OGTT (both P<0.001). The percentage decline was significantly smaller for CP. PYY and CCK increased equally after glucose in both groups.

CONCLUSION

Our patients with CP have more metabolic complications than our patients with NFPA. The levels of leptin and ghrelin at fasting status and after glucose seem to be altered in CP, whereas changes in insulin, PYY and CCK do not seem to be responsible for the metabolic changes in these patients.

Childhood craniopharyngioma: treatment strategies and outcomes

Craniopharyngiomas are embryogenic malformations of the sellar region. With an overall incidence of 0.5-2.0 new cases per million population per year, approximately 30-50% of all cases represent childhood craniopharyngioma. Therapy of choice in patients with favorable tumor localization is complete resection with a specific focus on maintaining functions of the optical nerve and hypothalamic-pituitary axes. In patients whose unfavorable tumor localization makes maintaining hypothalamic functionality surgically challenging, a limited resection followed by local irradiation is recommended. The overall survival rates are high (92%) but relapses and reduced QoL in survivors are also frequent. Because irradiation is efficient in preventing tumor progression, appropriate timing of post-surgical irradiation is currently under investigation in a randomized trial (KRANIOPHARYNGEOM 2007). Childhood craniopharyngioma should be recognized as a chronic disease requiring constant monitoring of the clinical and QoL consequences in order to provide optimal care of surviving patients.

Craniopharyngioma

Craniopharyngiomas are partly cystic embryogenic malformations of the sellar and parasellar region. With an overall incidence of 0.5-2.0 new cases per million population per year, approximately 30-50% of all cases represent childhood craniopharyngioma. Typical manifestations at diagnosis are some combination of headache, visual impairment, polyuria/polydypsia, growth retardation, and significant weight gain. Therapy of choice in patients with favorable tumor localization is complete resection with specific focus on maintaining functions of the optic nerve and hypothalamic-pituitary axes. In patients whose unfavorable tumor localization makes maintaining hypothalamic functionality surgically challenging, a limited resection followed by local irradiation is recommended. The overall survival rates are high (92%) but occurrences of reduced quality of life are also high. Recurrences after complete resection and progressions of residual tumor after incomplete resection are frequent postsurgical events. Because irradiation is efficient in preventing tumor progression, appropriate timing of postsurgical irradiation is currently under investigation in the randomized multinational trial KRANIOPHARYNGEOM 2007 that analyzes quality of life as primary endpoint. Childhood craniopharyngioma should be recognized as a chronic disease requiring constant monitoring of the clinical and quality of life consequences in order to provide optimal care of surviving patients.

Autonomic nervous system balance in children and adolescents with craniopharyngioma and hypothalamic obesity

OBJECTIVE

Dysregulation of the autonomic nervous system is thought to be involved in craniopharyngioma-related hypothalamic obesity (CRHO). Increased parasympathetic activity and decreased sympathetic activity have been suggested. We aimed to study autonomic activity using heart rate variability (HRV) and biochemical measures in youth with CRHO compared with controls and to explore relationships between obesity and autonomic indices.

DESIGN

A cross-sectional study of 16 youth with CRHO and 16 controls matched for sex, age, and BMI.

METHODS

Anthropometrics, fasting blood-work, resting energy expenditure (REE), 24-h HRV, and 24-h urine catecholamines were assessed. Quality of life, sleepiness, and autonomic symptoms were evaluated. Power spectral analysis of the HRV was performed.

RESULTS

HRV power spectral analysis parameters of both parasympathetic activity (mean high frequency (HF (ms(2))) 611±504 vs 459±336, P=0.325) and sympathetic activity (median low frequency/HF 1.62 (1.37, 2.41) vs 1.89 (1.44, 2.99), P=0.650) did not differ between the groups. Parasympathetic activity negatively correlated with central adiposity in both groups (r=-0.53, P=0.034 and r=-0.54, P=0.029) and sympathetic activity positively correlated with central adiposity in CRHO (r=0.51, P=0.043). Youth with CRHO had significantly lower REE; lower health and activity scores in the quality of life questionnaires, and higher sleepiness scores.

CONCLUSIONS

Autonomic activity was similar in CRHO and control subjects. The degree of central adiposity correlated negatively with parasympathetic activity and positively with sympathetic activity in children with CRHO. These results provide a new perspective regarding autonomic balance in this unique patient population.

Hypothalamic obesity: prevalence, associations and longitudinal trends in weight in a specialist adult neuroendocrine clinic

OBJECTIVE

Obesity is highly prevalent among adults with acquired, structural hypothalamic damage. We aimed to determine hormonal and neuroanatomical variables associated with weight gain and obesity in patients following hypothalamic damage and to evaluate the impact of early instigation of weight loss measures to prevent or limit the severity of obesity in these patients.

DESIGN

Retrospective study of 110 adults with hypothalamic tumours attending a specialist neuroendocrine clinic. BMI was calculated at diagnosis and at last follow-up clinic visit. Endocrine data, procedures, treatments and weight loss measures were recorded and all available brain imaging reviewed.

RESULTS

At last follow-up, 82.7% of patients were overweight or heavier (BMI≥25 kg/m(2)), 57.2% were obese (BMI≥30 kg/m(2)) and 14.5% were morbidly obese (BMI≥40 kg/m(2)). Multivariate analysis revealed that use of desmopressin (odds ratio (OR)=3.5; P=0.026), GH (OR=2.7; P=0.031) and thyroxine (OR=3.0; P=0.03) was associated with development of new or worsened obesity. Neuroimaging features were not associated with weight gain. Despite proactive treatments offered in clinic in recent years (counselling, dietetic and physical activity advice, and anti-obesity medications), patients have continued to gain weight.

CONCLUSIONS

Despite increased awareness, hypothalamic obesity is difficult to prevent and to treat. Improved understanding of the underlying pathophysiologies and multicentre collaboration to examine efficacy of novel obesity interventions are warranted.

Metabolic consequences of craniopharyingioma and their management

Most patients diagnosed with craniopharyngioma survive long-term, but suffer many consequences of the disease and its treatment. Among the metabolic consequences, there is a high prevalence of panhypopituitarism and diabetes insipidus, mainly due to the surgical treatment. Obesity is also more prevalent in these patients than in the general population, and gets worse with time. It is a consequence of a diminished basal metabolic rate and a lower physical activity compared to that of matched controls, with a similar or lower caloric intake. Many different hormonal alterations that could be responsible for those changes in the energy balance have been found. Patients whose tumor involved the hypothalamus are more prone to develop obesity and its consequences. Cardiovascular risk factors are also more prevalent in these patients, leading to a high cardiovascular morbidity and mortality. Sleep disturbances, dysfunction in thermoregulation and thirst and a lower bone mineral density can also be found. Although randomized clinical trials comparing different treatments are lacking, it looks like therapeutic strategies have a minor influence on the risk of long-term sequelae.

Bariatric surgery for morbid obesity in craniopharyngioma

OBJECTIVE

To retrospectively analyse the effectiveness of bariatric surgery for hypothalamic obesity in patients with craniopharyngioma (CP).

PATIENTS

Patients who developed morbid obesity after surgery for CP and who underwent laparoscopic gastric banding (LAGB), laparoscopic sleeve gastrectomy or gastric bypass were included (n = 9). Patients with common obesity who underwent bariatric surgery served as controls (LAGB n = 40, sleeve gastrectomy n = 49 and gastric bypass n = 54).

RESULTS

CP was diagnosed during childhood or adolescence [median (range) 10 (1-21) years] and age at bariatric surgery was 17 [12-30] years. Six patients underwent gastric banding [median follow-up 5.5 years (range 1-9)], 4 had a sleeve gastrectomy [median follow-up 2 (0.4-4) years] and two patients had gastric bypass surgery (median follow-up 3 years). Three patients had more than one type of bariatric surgery. Different from controls, no weight loss was observed after LAGB or sleeve gastrectomy. The two patients who had gastric bypass surgery lost body weight comparable with controls.

CONCLUSION

With LAGB and sleeve gastrectomy, no significant loss of body weight was achieved in young adult patients with craniopharyngioma-associated morbid obesity.

Childhood craniopharyngioma

Craniopharyngiomas (CP) are partly cystic embryogenic malformations of the sellar and parasellar region. With an overall incidence of 0.5-2.0 new cases/million population/year, approximately 30-50 % of all cases represent childhood CP. Typical manifestations at diagnosis are headache, visual impairment, polyuria/polydypsia, growth retardation, puberty development disturbances, and significant weight gain. Therapy of choice in children with favorable tumor localization is complete resection with the intention to maintain optic nerve and hypothalamic-pituitary functions. In children with unfavorable tumor localization (hypothalamic involvement), a limited resection followed by local irradiation is recommended. Although overall surgical survival rates are high (92 %), recurrence after complete resection and progression after incomplete resection are typical post-surgical events. Particularly troublesome for the pediatric patient are the disturbances to their pubescent development and overall growth. Accordingly, the appropriate time point of irradiation after incomplete resection is under investigation in a randomized multinational trial (KRANIOPHARYNGEOM 2007). Quality of life is substantially reduced in approximately 50 % of long-term survivors due to sequelae, notably morbid hypothalamic obesity. CP should be recognized as a chronic disease requiring constant monitoring of the early life as well as post-pubescent consequences and appropriate medical resources for treatment in order to provide optimal quality of survival for patients.

Hypothalamic obesity in children

Hypothalamic obesity is an intractable form of obesity syndrome that was initially described in patients with hypothalamic tumours and surgical damage. However, this definition is now expanded to include obesity developing after a variety of insults, including intracranial infections, infiltrations, trauma, vascular problems and hydrocephalus, in addition to acquired or congenital functional defects in central energy homeostasis in children with the so-called common obesity. The pathogenetic mechanisms underlying hypothalamic obesity are complex and multifactorial. Weight gain results from damage to the ventromedial hypothalamus, which leads, variously, to hyperphagia, a low-resting metabolic rate; autonomic imbalance; growth hormone-, gonadotropins and thyroid-stimulating hormone deficiency; hypomobility; and insomnia. Hypothalamic obesity did not receive enough attention, as evidenced by rarity of studies in this group of patients. A satellite symposium was held during the European Congress of Obesity in May 2011, in Istanbul, Turkey, to discuss recent developments and concepts regarding pathophysiology and management of hypothalamic obesity in children. An international group of leading researchers presented certain aspects of the problem. This paper summarizes the highlights of this symposium. Understanding the central role of the hypothalamus in the regulation of feeding and energy metabolism will help us gain insights into the pathogenesis and management of common obesity.

Pituitary tumors in childhood

PURPOSE OF REVIEW

This review focuses on recently published literature on pituitary tumors in children with special focus on craniopharyngioma and prolactinoma. Although most pituitary masses are benign neoplasms, they are associated with high morbidity and mortality related to their proximity to vital neurologic structures including the optic chiasm, hypophysis and hypothalamus, resulting in disruption of pituitary hormone secretion.

RECENT FINDINGS

The role of Wingless/β-beta catenin signaling and aryl hydrocarbon receptor-interacting protein mutations in pituitary tumor formation has been recognized. There is general agreement on optimal treatment of prolactinomas, although duration of medical therapy in children deserves more specific attention. Advances in imaging, medical, surgical and radiotherapy techniques have greatly increased survival rates for all pituitary tumors, but high recurrence rates after attempted complete resection and high progression rates after incomplete resection of craniopharyngioma remain troublesome. Long-term morbidity and late mortality of all pituitary tumors have become better appreciated with recent focus placed on severe obesity. A trend toward a more multidisciplinary approach for craniopharyngioma, including radiotherapy and chemotherapy, particularly when tumor burden involves the hypothalamus, continues.

SUMMARY

A vast amount of literature has been recently published, focusing on the management and long-term sequelae of all pituitary tumors in children. Craniopharyngioma remains the most challenging mass arising within sellar and parasellar areas, and optimal treatment continues to be hotly debated. Recognizing the rarity of pediatric pituitary tumors, the field would greatly benefit from more prospective multicenter trials, as well as from standardization of the assessment of preoperative function and post-treatment outcomes.

Functional neuroimaging in craniopharyngioma: a useful tool to better understand hypothalamic obesity?

OBJECTIVE

To use functional magnetic resonance imaging (fMRI) in craniopharyngioma (CP) patients to examine the hypothesis that hypothalamic damage due to CP and its treatment results in enhanced perception of food reward and/or impaired central satiety processing.

METHODS

Pre- and post-meal responses to visual food cues in brain regions of interest (ROI; bilateral nucleus accumbens, bilateral insula, and medial orbitofrontal cortex) were assessed in 4 CP patients versus 4 age- and weight-matched controls. Stimuli consisted of images of high- ('fattening') and low-calorie ('non-fattening') foods in blocks, alternating with non-food object blocks. After the first fMRI scan, subjects drank a high-calorie test meal to suppress appetite, then completed a second fMRI scan. Within each ROI, we calculated mean z-scores for activation by fattening as compared to non-fattening food images.

RESULTS

Following the test meal, controls showed suppression of activation by food cues while CP patients showed trends towards higher activation.

CONCLUSION

These data, albeit in a small group of patients, support our hypothesis that perception of food cues may be altered in hypothalamic obesity (HO), especially after eating, i.e. in the satiated state. The fMRI approach is encouraging for performing future mechanistic studies of the brain response to food cues and satiety in patients with hypothalamic or other forms of childhood obesity.

Bariatric surgery in hypothalamic obesity

Craniopharyngiomas (CP) are epithelial neoplasms generally found in the area of the pituitary and hypothalamus. Despite benign histology, these tumors and/or their treatment often result in significant, debilitating disorders of endocrine, neurological, behavioral, and metabolic systems. Severe obesity is observed in a high percentage of patients with CP resulting in significant comorbidities and negatively impacting quality of life. Obesity occurs as a result of hypothalamic damage and disruption of normal homeostatic mechanisms regulating energy balance. Such pathological weight gain, termed hypothalamic obesity (HyOb), is often severe and refractory to therapy. Unfortunately, neither lifestyle intervention nor pharmacotherapy has proven effective in the treatment of HyOb. Given the limited choices and poor results of these treatments, several groups have examined bariatric surgery as a treatment alternative for patients with CP-HyOb. While a large body of evidence exists supporting the use of bariatric surgery in the treatment of exogenous obesity and its comorbidities, its role in the treatment of HyOb has yet to be defined. To date, the existing literature on bariatric surgery in CP-HyOb is largely limited to case reports and series with short term follow-up. Here we review the current reports on the use of bariatric surgery in the treatment of CP-HyOb. We also compare these results to those reported for other populations of HyOb, including Prader-Willi Syndrome, Bardet-Biedl syndrome, and hypothalamic melanocortin signaling defects. While initial reports of bariatric surgery in CP-HyOb are promising, their limited scope makes it difficult to draw any substantial conclusions as to the long term safety and efficacy of bariatric surgery in CP-HyOb. There continues to be a need for more robust, controlled, prospective studies with long term follow-up in order to better define the role of bariatric surgery in the treatment of HyOb.

Diagnostics, treatment, and follow-up in craniopharyngioma

Craniopharyngiomas are partly cystic embryogenic malformations of the sellar and parasellar region, with up to half the 0.5-2.0 new cases per million population per year occur in children and adolescents. Diagnosis profile for pediatric and adult craniopharyngioma is characterized by a combination of headache, visual impairment, and polyuria/polydipsia, which can also include significant weight gain. In children, growth retardation, and/or premature puberty often occur later or postoperatively. Recommended therapy with favorable tumor localization is complete resection; with unfavorable tumor localization (optic nerve and/or hypothalamic involvement), consensus is still pending whether a limited resection followed by local irradiation is more prudent. Even though overall survival rates are high (92%), recurrences after complete resection and progressions after incomplete resection can be expected. Accordingly, a randomized multinational trial (KRANIOPHARYNGEOM 2007) has been established to identify optimal diagnosis, treatment (particularly the ideal time point of irradiation after incomplete resection), and quality of life strategies of this chronic disease - most notably the morbid hypothalamic obesity in ∼50% of long-term survivors. We report on craniopharyngioma origins, its pathological manifestations, and specific challenges these sequelae pose regarding diagnosis, treatment, and life-long multi-discipline quality of life management for both adult and childhood craniopharyngioma patients.

A novel rodent model that mimics the metabolic sequelae of obese craniopharyngioma patients

Patients with craniopharyngioma (CP), a tumor located in the pituitary and/or hypothalamus, are susceptible to developing obesity and many metabolic complications. The study aim was to create a rodent model that mimics the complex neuroanatomical and metabolic disturbances commonly seen in obese CP patients. We compared the metabolic phenotype of animals with three distinct types of hypothalamic lesions: 1) destruction of the arcuate nucleus (ARC) induced by monosodium glutamate (MSG), 2) electrolytic lesion of the adjacent ventromedial nucleus (VMN) alone, 3) both the VMN and dorsomedial nucleus (DMN), or a 4) combined medial hypothalamic lesion (CMHL) affecting the VMN, DMN, and the ARC. Only the CMHL model exhibited all key features observed in patients with hypothalamic obesity induced by CP. These features included excessive weight gain due to increased adiposity, increased food intake, and pronounced hyperinsulinemia and hyperleptinemia. Similar to characteristics of patients with CP, CMHL animals exhibited reduced plasma levels of alpha-melanocyte stimulating hormone and reduced ambulatory activity compared with weight-matched controls. Therefore, the CMHL model best mimics the complex metabolic abnormalities observed in obese CP patients compared with lesions to other hypothalamic areas and provides a foundation for future pharmacological approaches to treat obesity in children with hypothalamic damage.

Long term sequelae of pediatric craniopharyngioma - literature review and 20 years of experience

Craniopharyngioma are rare histologically benign brain tumors that develop in the pituitary-hypothalamic area. They may invade nearby anatomical structures causing significant rates of neurological, neurocognitive, and endocrinological complications including remarkable hypothalamic damage. Information regarding long term implications of the tumors and treatment in the pediatric population is accumulating, and treatment goals appear to be changing accordingly. In this review we aim to present data regarding long term complications of craniopharyngioma in children and adolescents and our experience from a large tertiary center. Hypothalamic dysfunction was noted to be the most significant complication, adversely affecting quality of life in survivors. Obesity, fatigue, and sleep disorders are the most notable manifestations of this dysfunction, and treatment is extremely difficult. Changes in management in recent years show a potential for improved long term outcomes; we found a trend toward less aggressive surgical management and increasing use of adjuvant treatment, accompanied by a decrease in complication rates.

Effects of methylphenidate on weight gain and food intake in hypothalamic obesity

For patients with a craniopharyngioma (CP), treatment of hypothalamic obesity (HO) and hyperphagia following resection and/or radiotherapy is extremely difficult and few reports have been published on potential drug therapies. Psychomotor stimulant methylphenidate (MPH) has been reported to inhibit food intake (FI). In this paper, we report reduction of body mass index (BMI) and appetite in an adolescent CP patient suffering from HO. We then tested the ability of MPH to attenuate the FI and body weight (BW) gain in a rat model consistent with the neuroanatomical and metabolic disturbances commonly observed in obese CP patients. Specifically, we used a novel electrolytically generated combined medial hypothalamic lesion (CMHL) affecting the arcuate nucleus, ventromedial hypothalamic nucleus, and dorsomedial hypothalamic nucleus to induce hyperphagia, rapid weight gain, and adiposity. Both CMHL and control animals (n = 7 per group) were administered either methylphenidate HCl (MPH; 20 mg kg(-1) day(-1)) or saline for 4 days in a crossover design experiment 28 weeks post-surgery. A significant decrease in percent baseline FI (CMHL -23%, p = 0.008; control -20%, p = 0.002) and percent change in BW (CMHL -1.97%/4 days, p = 0.011; control -1.75%/4 days, p = 0.003) was observed during MPH treatment as compared to saline.

CONCLUSION

This study shows MPH treatment of severely obese CMHL rats resulted in significantly reduced FI and BW loss.

Hypothalamic obesity in patients with craniopharyngioma: profound changes of several weight regulatory circuits

One of the most striking examples of dysfunctional hypothalamic signaling of energy homeostasis is observed in patients with hypothalamic lesions leading to hypothalamic obesity (HO). This drastic condition is frequently seen in patients with craniopharyngioma (CP), an embryological tumor located in the hypothalamic and/or pituitary region, frequently causing not only hypopituitarism, but also leading to damage of medial hypothalamic nuclei due to the tumor and its treatment. HO syndrome in CP patients is characterized by fatigue, decreased physical activity, uncontrolled appetite, and morbid obesity, and is associated with insulin and leptin resistance. Mechanisms leading to the profoundly disturbed energy homeostasis are complex. This review summarizes different aspects of important clinical studies as well as data obtained in rodent studies. In addition a model is provided describing how medial hypothalamic lesion can interact simultaneously with several weight-regulating circuitries.

Increased daytime sleepiness in patients with childhood craniopharyngioma and hypothalamic tumor involvement: review of the literature and perspectives

Childhood craniopharyngiomas are rare embryogenic malformations of the sellar region, presumably derived from Rathke cleft epithelium. The overall survival rates after neurosurgical intervention and/or irradiation are high (92%). However, the quality of survival is frequently impaired due to endocrine deficiencies, sleep disturbances, daytime sleepiness, and severe obesity caused by hypothalamic lesions. Based on self-assessment using nutritional diaries, caloric intake was similar in patients and BMI-matched controls. Analyses of physical activity by accelerometric measurements showed a markedly lower level of physical activity. Significant daytime sleepiness and disturbances of circadian rhythms have been demonstrated in obese childhood craniopharyngioma patients. Daytime sleepiness and obesity in these patients were both correlated with low nocturnal and early morning melatonin levels. Polysomnographic studies in patients with severe daytime sleepiness revealed sleeping patterns typical for secondary narcolepsy. Reports on a beneficial effect of treatment with central stimulating agents supported the hypothesis that secondary narcolepsy should be considered as a rare cause for severe daytime sleepiness in patients with childhood craniopharyngioma.