Central diabetes insipidus: Is it Langerhans cell histiocytosis of the pituitary stalk? A diagnostic pitfall

Incidence and Predictors for Oncologic Etiologies in Chinese Children with Pituitary Stalk Thickening

BACKGROUND

With the increasing use of magnetic resonance imaging (MRI) in the evaluation of children with endocrine disorders, pituitary stalk thickening (PST) poses a clinical conundrum due to the potential for underlying neoplasms and challenges in obtaining a tissue biopsy. The existing literature suggests Langerhans cell histiocytosis (LCH) to be the commonest (16%) oncologic cause for PST, followed by germ cell tumors (GCTs, 13%) (CCLG 2021). As the cancer epidemiology varies according to ethnicity, we present herein the incidence and predictors for oncologic etiologies in Hong Kong Chinese children with PST.

METHODS

Based on a territory-wide electronic database, we reviewed patients aged < 19 years who presented to three referral centers with endocrinopathies between 2010 and 2022. Records for patients who underwent at least one MRI brain/pituitary were examined (n = 1670): those with PST (stalk thickness ≥ 3 mm) were included, while patients with pre-existing cancer, other CNS and extra-CNS disease foci that were diagnostic of the underlying condition were excluded.

RESULTS

Twenty-eight patients (M:F = 10:18) were identified. The median age at diagnosis of PST was 10.9 years (range: 3.8-16.5), with central diabetes insipidus (CDI) and growth hormone deficiency (GHD) being the most frequent presenting endocrine disorders. At a median follow-up of 4.8 years, oncologic diagnoses were made in 14 patients (50%), including 13 GCTs (46%; germinoma = 11, non-germinoma = 2) and one LCH (4%). Among patients with GCTs, 10 were diagnosed based on histology, two by abnormal tumor markers and one by a combination of histology and tumor markers. Three patients with germinoma were initially misdiagnosed as hypophysitis/LCH. The cumulative incidence of oncologic diagnoses was significantly higher in boys and patients with PST at presentation ≥6.5 mm, CDI or ≥2 pituitary hormone deficiencies at presentation and evolving hypopituitarism (all p < 0.05 by log-rank).

CONCLUSIONS

A higher rate of GCTs was observed in Chinese children with endocrinopathy and isolated PST. The predictors identified in this study may guide healthcare providers in Asia in clinical decision making. Serial measurement of tumor markers is essential in management.

Pituitary Stalk Germ Cell Tumors: Retrospective Case Series and Literature Review

OBJECTIVE

Intracranial germ cell tumors with isolated pituitary stalk involvement are rare. Early recognition and long-term monitoring deserve further exploration.

METHODS

A retrospective study reviewing eleven intracranial germ cell tumor patients with isolated pituitary stalk involvement was performed.

RESULTS

Seven boys and four girls who presented with a hyperintense pituitary stalk on postcontrast T1-weighted magnetic resonance imaging without a posterior pituitary signal were included. The average maximum width of the pituitary stalk was 5.2 ± 1.6 mm. Polydipsia and polyuria occurred in all patients, followed by growth retardation, fatigue, and amenorrhoea. Eight patients (72%) had concomitant partial anterior pituitary hormone deficiency. Seven patients initially had elevated human chorionic gonadotropin levels. After chemoradiotherapy, ten patients attended follow-up. Central diabetes insipidus remained in all survivors, and four (40%) of them had concomitant partial anterior pituitary hormone deficiency, primarily of growth hormone and insulin-like growth factor-1. The causes of the delayed diagnosis of previous studies were mainly negative tumor markers and the initial pathological diagnosis of autoimmune diseases.

CONCLUSION

Isolated pituitary stalk lesions could be a signal of intracranial germ cell tumors, especially coexisting with diabetes insipidus, hypopituitarism, and a worse response to glucocorticoid therapy. Negative results of tumor markers and pathology could not exclude the diagnosis. Chemoradiotherapy is an effective therapy, leaving mild-t-moderate hypothalamus-pituitary dysfunction. This rare neuroimaging feature may be used as a factor to predict long-term neuroendocrine outcomes.

Paediatric Langerhans Cell Histiocytosis Disease: Long-Term Sequelae in the Hypothalamic Endocrine System

Langerhans cell histiocytosis (LCH) is a disorder of the mononuclear phagocyte system that can affect almost any organ and system. The most common central nervous system (CNS) manifestation in LCH is the infiltration of the hypothalamic-pituitary region leading to destruction and neurodegeneration of CNS tissue. The latter causes the most frequent endocrinological manifestation, that is, central diabetes insipidus (CDI), and less often anterior pituitary hormone deficiency (APD). The reported incidence of CDI is estimated between 11.5 and 24% and is considered a risk factor for neurodegenerative disease and APD. Three risk factors for development of CDI are recognized in the majority of the studies: (1) multisystem disease, (2) the occurrence of reactivations or active disease for a prolonged period, and (3) the presence of craniofacial bone lesions. Since CDI may occur as the first manifestation of LCH, differential diagnosis of malignant diseases like germ cell tumours must be made. APD is almost always associated with CDI and can appear several years after the diagnosis of CDI. Growth hormone is the most commonly affected anterior pituitary hormone. Despite significant advances in the knowledge of LCH in recent years, little progress has been made in preventing long-term sequelae such as those affecting the hypothalamic-pituitary system.

Clinical aspects of autoimmune hypothalamitis, a variant of autoimmune hypophysitis: Experience from one center

Objective

Autoimmune hypothalamitis (AHT) is a rare inflammatory disorder that involves the hypothalamus. It remains unclear whether autoimmune hypophysitis (AH) and AHT represent different diseases or different aspects of the same disease. Thus, further investigation of AHT is required.

Methods

A retrospective review of medical and pathological records of AHT patients from the Chinese PLA General Hospital were examined from January 1, 2005 to May 1, 2017. Clinical data, treatments, and outcomes were investigated.

Results

Five female patients were identified (median age, 42.6 years). Symptoms included central diabetes insipidus, hypopituitarism, hyperprolactinemia, headache, and hypothalamic syndrome. The following hormonal deficits were noted: follicle-stimulating hormone, luteinizing hormone, adrenocorticotropic hormone, thyroid stimulating hormone, and growth hormone. One patient underwent high-dose methylprednisolone pulse treatment (HDMPT) and azathioprine plus intensity modulated radiation therapy (IMRT), and two patients underwent HDMPT and two rounds of replacement therapy. During follow-up, one patient died because of non-compliance with therapy and the others were in remission or they recovered.

Conclusions

AHT had similar MRI results, pathology, and treatment compared with AH. Thus, it may be a subtype of AH, and AHT patients may also show hypothalamic syndrome.

Evaluation and treatment of Langerhans cell histiocytosis patients with central nervous system abnormalities: Current views and new vistas

Central nervous system (CNS) involvement in Langerhans cell histiocytosis (LCH) can include mass lesions of the hypothalamic pituitary axis, choroid plexus, cerebrum, and cerebellum or magnetic resonance imaging (MRI) signal abnormalities of the cerebellum, pons, and basal ganglia. The term neurodegenerative (ND) CNS-LCH has been given to the MRI signal abnormalities and neurologic dysfunction, although initially patients may have no clinical symptoms. Standardized evaluations to better understand the natural history and response to therapy are needed. We propose guidelines for clinical, radiologic, and physiologic tests as a framework for developing the best methods of evaluation, which can then be tested in prospective treatment protocols.

Adult leukoencephalopathies with prominent infratentorial involvement can be caused by Erdheim-Chester disease

BACKGROUND

Leukoencephalopathies with prominent involvement of cerebellum and brainstem, henceforward called prominent infratentorial leukoencephalopathies (PILs), encompass a variety of inherited and acquired white matter diseases. Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis likely under-diagnosed as cause of adult PIL.

METHODS

We reviewed the clinical and laboratory information of ten consecutive sporadic adult patients with PIL of unknown origin, who were investigated for ECD.

RESULTS

There were seven males and three females; mean age at clinical onset was 49.6 years (range 38-59); cerebellar ataxia with or without other neurological symptoms was the only or the main clinical manifestation; diabetes insipidus was present in three individuals. Eight patients had white matter focal supratentorial abnormalities, in addition to the infratentorial white matter changes. Six out of eight patients had spinal cord lesions. Thoraco-abdominal CT showed periaortic sheathing in two patients, whole-body FDG-PET revealed increased glucose uptake in the long bones of the legs in five patients, brain FDG-PET showed overt infratentorial hypermetabolism in one patient. In eight patients, ECD was confirmed by bone scintigraphy, pathological data, or both. Two ECD patients treated with vemurafenib showed a marked improvement of neurological symptoms and brain MRI abnormalities at 1 year follow-up.

CONCLUSIONS

Symptoms of PIL can be the only clinical manifestation of ECD. Adult patients with PIL of unknown origin should undergo investigations aimed at unveiling ECD, including bone scintigraphy and whole-body FDG-PET. The early diagnosis allows starting disease-modifying therapies of an otherwise life-threatening disease.

Clinical presentation and outcome of children with central diabetes insipidus associated with a self-limited or transient pituitary stalk thickening, diagnosed as infundibuloneurohypophysitis

OBJECTIVE

Despite lymphocytic or autoimmune infundibuloneurohypophysitis (INH) is an increasingly recognized aetiology in children with central diabetes insipidus (CDI); clinical data on epidemiology (clinical evolution, predisposing factors, complications), diagnosis and management of this entity are limited and mostly based on published case reports. The aim of this study was to gain a broader insight in the natural history of this disease by analysing the clinical presentation, radiological pituitary stalk changes, associated autoimmunity and hormonal deficiencies in children with CDI and a self-limiting or transient stalk thickening (ST), diagnosed as autoimmune infundibuloneurohypophysitis, during the last 15 years in four Belgian university hospitals.

DESIGN AND PATIENTS

The medical files of nine CDI patients with a ST at initial presentation and no signs of Langerhans cell histiocytosis or germinoma at presentation and/or during follow-up of more than 1.5 years were reviewed.

RESULTS

Age at presentation ranged from 3 to 14 years. Two patients had a positive family history of autoimmunity. Three children presented with associated growth failure, two with nausea and one with long-standing headache. Median maximal diameter of the stalk was 4.6 mm (2.7-10 mm). Four patients had extra-pituitary brain anomalies, such as cysts. One patient had central hypothyroidism, and another had a partial growth hormone deficiency at diagnosis. Within a mean follow-up of 5.4 (1.5-15) years, stalk thickening remained unchanged in two patients, regressed in one and normalized in six children. CDI remained in all, while additional pituitary hormone deficiencies developed in only one patient.

CONCLUSIONS

In this series of children INH with CDI as initial presentation, CDI was permanent and infrequently associated with anterior pituitary hormone deficiencies, despite a frequent association with nonstalk cerebral lesions.

A Case of Langerhans Cell Histiocytosis Manifested as a Suprasellar Mass

Langerhans cell histiocytosis (LCH) has diverse clinical manifestations, including intracranial mass lesions. We report a case of LCH that manifested as a suprasellar mass, and initially misdiagnosed as a germ cell tumor. A 29-year-old woman presented with polyuria, polydipsia and amenorrhea. Laboratory findings revealed hypopituitarism with central diabetes insipidus, and a suprasellar mass and a pineal mass were observed on magnetic resonance imaging. Under the clinical impression of a germ cell tumor, the patient was treated with germ cell tumor chemotherapy (cisplatin and etoposide) and radiation therapy without biopsy. After initial shrinkage of the lesions, further growth of the tumor was observed and a biopsy was performed. The histopathology revealed LCH. After chemotherapy according to the LCH III protocol, the tumor disappeared. She is on regular follow up for 5 years without relapse. The present findings indicate that LCH should be included in the differential diagnosis of a suprasellar mass, even in adults, especially when it manifests with diabetes insipidus. This case also underscores the importance of a histopathologic diagnosis in patients with suprasellar tumors before the initiation of a specific therapy, even if the clinical findings are highly suggestive of a specific diagnosis.

Treatment of patients with hypothalamic-pituitary lesions as adult-onset Langerhans cell histiocytosis

We report four cases of adult-onset Langerhans cell histiocytosis (LCH) with central nervous system (CNS) lesions in the hypothalamic-pituitary region. The first clinical symptoms were diabetes insipidus (two patients), hypothyroidism (one patient), and decreased libido/erectile dysfunction (one patient). Diagnosis was delayed as the CNS lesion was not initially suspected to be secondary to LCH, with a median time from symptom onset to treatment of 3.0 (range <1-5.3) years. In three patients, the tumor mass was effectively reduced by chemotherapy; however, all patients continue to exhibit hypopituitarism. Early diagnosis and initiation of treatment are required to improve the outcome of CNS-LCH in adult patients.

Pituitary tumours: inflammatory and granulomatous expansive lesions of the pituitary

Inflammatory and granulomatous diseases of the pituitary are rare causes of sellar masses. Lymphocytic hypophysitis is the most relevant of these disorders, and it is characterised by autoimmune pathogenesis with focal or diffuse inflammatory infiltration and varying degrees of pituitary gland destruction. Endocrine symptoms may include partial or total hypopituitarism, with adrenocorticotropic hormone (ACTH) deficiency being the earliest and most frequent alteration. Pituitary abscess is a rare but potentially life-threatening disease and, in 30-50% of patients, anterior pituitary hormone deficiencies or central diabetes insipidus (DI) at onset may be observed: the earliest manifestation being growth hormone deficiency (GHD), followed by follicle-stimulating hormone (FSH)/luteinising hormone (LH), thyroid-stimulating hormone (TSH) and ACTH deficiencies. Fungal infections of the pituitary are also very rare and include aspergillosis and coccidioidomycosis. Concerning pituitary involvement in systemic diseases, in sarcoidosis endocrine complications are rare, but the hypothalamus and pituitary are the glands most commonly affected. DI is reported in approximately 25-33 % of all neurosarcoidosis cases and is the most frequently observed endocrine disorder. Hyperprolactinaemia and anterior pituitary deficiencies may also occur. Rarely, partial or global anterior pituitary dysfunction may be present also in Wegener's granulomatosis, either at onset or in the course of the disease, resulting in deficiency of one or more of the pituitary axes. Other forms of granulomatous pituitary lesions include idiopathic giant cell granulomatous hypophysitis, Takayasu's disease, Cogan's syndrome and Crohn's disease. The hypotalamic-pituitary system is involved mainly in children with Langerhans' cells histiocytosis who develop DI, which is the most common endocrine manifestation. Anterior pituitary dysfunction is found more rarely and is almost invariably associated with DI. Pituitary involvement may also be observed in another form of systemic hystiocitosis, that is, Erdheim-Chester disease. Tuberculosis is a rare cause of hypophysitis, which may present with features of anterior pituitary dysfunction, such as hypopituitarism with hyperprolactinaemia. In conclusion, in patients with a sellar mass and unusual clinical presentation (DI, neurological symptoms), aggressiveness and onset and in the presence of systemic diseases, inflammatory and granulomatous pituitary lesions should be carefully considered in differential diagnosis.

Occurrence of a germinoma 22 years after resection of a mature cerebral teratoma

We present the rare case of a 31-year-old man who developed a germinoma 22 years after resection of a mature teratoma of the pineal region. The initial stereotactic biopsy showed a granulomatous inflammation, but no malignant cells. The correct diagnosis could only be confirmed in a second cerebral biopsy, allowing for proper treatment with radiation therapy. The need to consider metachronous germinoma in this setting is discussed.

Rare sellar lesions

Sellar masses are associated most commonly with pituitary adenomas. Many other neoplastic, inflammatory, infectious, and vascular lesions, however, may affect the sellar region and mimic pituitary tumors. These lesions must be considered in a differential diagnosis. This article describes the characteristics of rare sellar masses that provide clues to their differential diagnosis.

Systemic and endocrine manifestations of Langerhans' cell histiocytosis: current concepts in diagnosis and management

Langerhans' cell histiocytosis (LCH) is a rare disease of unknown etiology and variable biologic behavior and course. Almost every organ can be affected; however, it frequently involves the bones, lungs, skin and lymph nodes. LCH exhibits a particular predilection for involvement of the hypothalamo-pituitary axis resulting in diabetes insipidus and/or other anterior pituitary deficiencies. Although LCH can sometimes resolve spontaneously, it usually follows a chronic course and systemic treatment is mandatory for the management of multisystem disease. However, a significant number of patients will develop at least one permanent sequela as a consequence of the disease, with diabetes insipidus being the most common. A multidisciplinary approach is always needed in diagnosis, treatment and follow-up of all patients with LCH.

Granulomatous tissue response in germinoma, a diagnostic pitfall in endoscopic biopsy

We report a case of a 24-year-old man with a right thalamic germinoma that initially mimicked a granulomatous inflammation, compatible with neurosarcoidosis based on clinical symptoms, imaging results and histology of an endoscopically navigated biopsy. A second biopsy, prompted by clinical course, and performed openly from parieto-lateral revealed the underlying germinoma, obscured in the first biopsy by a granulomatous tissue response, particularly at the tumor edge. The present case highlights granulomatous inflammatory tissue response on the tumor edge of germinoma as a tumor-immanent diagnostic challenge. This diagnostic problem is aggravated by stereotactic and endoscopic approaches. We conclude that granulomatous inflammation in a specimen obtained by biopsy of a midline lesion should always be considered for the differential diagnosis of germinoma. Stereotactic and endoscopic surgery should sample several different target points within the lesion. Because of tumor heterogeneity of germinoma, the open biopsy approach is advantageous compared to endoscopic or stereotactic techniques for germinoma and should be considered if a germinoma is in the differential diagnosis and if allowed by the clinical situation.

The diagnosis of children with central diabetes insipidus

Central diabetes insipidus is the end result of a number of different diseases that affect the hypothalamic-neurohypophyseal system. In many patients, especially children and young adults, it is caused by the destruction or degeneration of neurons that originate in the supraoptic and paraventricular nuclei of the hypothalamus. The known causes of these lesions include germinoma or craniopharyngioma; Langerhans cell histiocytosis; local inflammatory, autoimmune or vascular diseases; trauma resulting from surgery or an accident; sarcoidosis; metastases; and midline cerebral and cranial malformations. In rare cases, genetic defects in AVP synthesis that are inherited as autosomal dominant, autosomal recessive or X-linked recessive traits are the underlying cause. Accurate diagnostic differentiation is essential for both safe and effective disease management. Proper etiological diagnosis can be achieved via a series of steps that start with clinical observations and then progress, as needed, to more sophisticated methods. Indeed, magnetic resonance imaging (MRI) represents the examination method of choice for evaluating hypothalamic-pituitary-related endocrine diseases due to its ability to provide strongly-contrasted high-resolution multi-planar and spatial images. Specifically, MRI allows a detailed and precise anatomical study of the pituitary gland by differentiating between the anterior and posterior pituitary lobes. MRI identification of pituitary hyperintensity in the posterior part of the sella, now considered to be a clear marker of neurohypophyseal functional integrity, together with careful analysis of pituitary stalk shape and size, have provided the most striking recent findings contributing to the diagnosis and understanding of some forms of 'idiopathic' central diabetes insipidus.

Anomalies de la tige pituitaire à l’IRM : aspects étiologiques à propos de 11 cas

Newer techniques of magnetic resonance imaging (MRI) describe more accurately pituitary stalk abnormalities such as infections, infiltrative lesions and tumors. In absence of all the above mentioned etiological factors, genetics defects are suspected, mainly when other malformations are equally present. We attempt to show through 11 observations the variability of pathologies involving the pituitary stalk with their respective clinical and radiological features and associated endocrine abnormalities. This is a retrospective study of 7 men (67%) and 4 women (33%), mean age of 28 year (range: 15 to 53) in whom pituitary MRI was performed for hypopituitarism, diabetes insipidus or hyperprolactinemia. Three patients had brain MRI for an extra-pituitary condition. The pituitary MRI showed a stalk section in 3 cases (27%), atrophy in 1 case and thickening in 7 cases (67%). The pituitary stalk anomaly was associated with hyperprolactinemia in 3 cases (27%), central diabetes insipidus in 4 cases (36%), growth hormone deficiency in 4 cases (36%), adrenal insufficiency in 5 cases (45%), hypogonadism in 5 cases (45%) and hypothyroidism in one case (9%). Established diagnoses were: sellar metastasis in 2 cases (18%), Langerhans' histocytosis, tuberculosis and autoimmune hypophysitis respectively in 3 cases (9%). In 6 cases (54%), no clear etiology was found. Given the multitude of pituitary stalk pathologies, a detailed etiologic inquiry must be performed in order to detect elements able to reclassify an initially idiopathic disorder.

The role of radiation therapy in benign diseases

Although adequate prospective data are lacking, radiation therapy seems to be effective for many benign diseases and remains one of the treatment modalities in the armamentarium of medical professionals. Just as medication has potential adverse effects, and surgery has attendant morbidity, irradiation sometimes can be associated with acute and chronic sequelae. In selecting the mode of treatment, most radiation oncologists consider the particular problem to be addressed and the goal of therapy in the individual patient. It is the careful and judicial use of any therapy that identifies the professional. With an understanding of the current clinical data, treatment techniques, cost, and potential detriment, the goal is to provide long-term control of the disease while minimizing unnecessary treatment and potential risks of side effects. The art lies in balancing benefits against risks.