Association of BRAF V600E with Hypothalamic-Pituitary-Adrenal Axis Involvement in Erdheim-Chester Disease

Clinical, Laboratory, and Imaging Features Associated with Arginine Vasopressin Deficiency (Central Diabetes Insipidus) in Erdheim-Chester Disease (ECD)

PURPOSE

Erdheim-Chester disease (ECD) is an L Group Langerhans histiocytosis associated with pathogenic variants within the MAPK pathways, most commonly the BRAF gene. We analyzed prevalence, genetic, biochemical, and pituitary imaging features associated with arginine vasopressin deficiency (AVP-D), one of the most common endocrinopathies in ECD.

METHODS

A cross-sectional descriptive study of 61 subjects with ECD was conducted at a clinical research center from January 2011 to December 2018, with molecular genetics, baseline biochemical and pituitary endocrine function studies, and dedicated pituitary MRI (or CT) studies. AVP-D and anterior pituitary endocrinopathies (hypothyroidism, hypogonadism, adrenal insufficiency and panhypopituitarism) were assessed. Students' t-tests, nonparametric tests, Fisher's exact tests, and logistic regression were employed for analysis.

RESULTS

In total, 22 out of 61 subjects (36%; 19 males and 3 females) had AVP-D; 18 subjects with AVP-D were in active treatment with desmopressin. Those with versus without AVP-D were younger [mean (±SD): 50.00 (±10.45) vs. 56.72 (±10.45) years], had higher prevalence of BRAF V600E pathogenic variants [68% vs. 43%], lower IGF-1 [mean (±SD): 137.05 (±67.97) vs. 175.92 (±61.89) ng/mL], lower urine osmolality [416.00 (250.00-690.00) vs. 644.50 (538.75-757.75)) mOsm/kg], and a higher burden of central hypogonadism [81.82% vs. 36.00%], central hypothyroidism [23% vs. 2.5%], panhypopituitarism [41% vs. 0%], anterior pituitary endocrine deficits, absent posterior pituitary bright spots [63.64% vs. 20.51%], and abnormal pituitary imaging. In adjusted models, [OR (95%CI)] BRAF V600E mutation [7.38 (1.84-39.01)], central hypogonadism [6.193 (1.44-34.80)], primary hypothyroidism [13.89 (1.401-406.5)], absent posterior pituitary bright spot [12.84 (3.275-65.04)], and abnormal pituitary imaging [10.60 (2.844-48.29)] were associated with higher odds of having AVP-D.

CONCLUSIONS

AVP-D is common in ECD and accompanied by a higher burden of pituitary endocrinopathies, BRAF V600E pathogenic variants, abnormal pituitary imaging, and absent posterior pituitary bright spots.

Survivorship Issues in Adult Patients With Histiocytic Neoplasms

Adult-onset histiocytoses (AOH), primarily Rosai-Dorfman disease (RDD), Erdheim-Chester Disease (ECD), and adult Langerhans cell histiocytosis (ALCH), are a group of related histiocytic neoplastic disorders featuring multisystemic manifestations. The disorders are largely incurable, and are essentially chronic neoplastic diseases with a variable prognosis. Prompt diagnosis and treatment is important to prevent debilitating and even life-threatening complications. Survivorship issues abound in AOH, due to their multisystemic manifestations and the sometimes recalcitrant chronic inflammation, which can lead to other debilitating complications such as fatigue, weakness, and pain. Because these disorders are rare, few healthcare professionals are proficient in their management; therefore the aim of these guidelines is to offer guidance on how to manage patients, and how to create survivorship care plans through the efforts of an interdisciplinary team.

Pituitary Imaging Abnormalities and Related Endocrine Disorders in Erdheim-Chester Disease

Simple Summary

Erdheim–Chester disease (ECD) is a rare histiocytic neoplasm that is frequently associated with hypothalamic–pituitary gland involvement leading to endocrine dysfunctions. Frequently, endocrinopathy is permanent and precedes the diagnosis of ECD and may also develop during the course of treatment. However, the exact nature and frequency of hypothalamic–pituitary involvement are unknown. We studied a natural history cohort of 61 subjects with Erdheim–Chester disease and found abnormal pituitary imaging in 47.5% of cases, associated with panhypopituitarism, diabetes insipidus, and a higher median number of pituitary endocrinopathies. These data confirm and significantly extend previous reports of centrally occurring endocrine dysfunction and highlight the need for routine imaging and systematic assessment of hypothalamic–pituitary endocrine function in patients with ECD.

Abstract

Purpose: We examined abnormal pituitary imaging (API) and associated endocrine dysfunction in subjects with ECD. Methods: A cross-sectional descriptive examination of a natural history cohort study diagnosed with ECD was conducted at a clinical research center. Subjects underwent baseline endocrine tests of anterior and posterior pituitary function and dedicated pituitary gland MRI scans. We determined the frequency of various pituitary imaging abnormalities in ECD and assessed its relationships with age, sex, body mass index (BMI), BRAF V600E status, high sensitivity C-reactive protein (hsCRP), erythrocyte sedimentation rate (ESR), pituitary hormone deficits and number, diabetes insipidus (DI), and panhypopituitarism. Results: Our cohort included 61 subjects with ECD [age (SD): 54.3 (10.9) y, 46 males/15 females]. API was present in 47.5% (29/61) of ECD subjects. Loss of the posterior pituitary bright spot (36.1%) followed by thickened pituitary stalk (24.6%), abnormal enhancement (18.0%), and pituitary atrophy (14.8%) were the most common abnormalities. DI and panhypopituitarism were more frequent in subjects with API without differences in age, sex distribution, hsCRP, ESR, and BRAF V600E status compared to normal pituitary imaging. Conclusions: We noted a high burden of API and endocrinopathies in ECD. API was highly associated with the presence of panhypopituitarism and DI. Therefore, a thorough assessment of hypothalamic–pituitary integrity should be considered in subjects with ECD.