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OBJECTIVES: VEXAS syndrome is an autoinflammatory disease caused by somatic mutation of UBA1 and affects multiple organ systems. Involvement of the kidneys is not well characterized. We aimed to investigate the incidence, risk factors and histopathologic features of acute kidney injury (AKI) in VEXAS syndrome. METHODS: Patients with genetically confirmed UBA1 mutation consistent with VEXAS were included. Charts were manually reviewed. Cox regression analysis was used to identify variables associated with time-to-first acute kidney injury (AKI) event. For patients with a kidney biopsy, histopathologic findings were reviewed. RESULTS: Eighty-one patients were included, all white men, with a mean age of 66.3±8.6 years. Median (IQR) follow up was 3.5 (2.1-5.2) years during which 20 (25%) developed AKI and 22% died. AKI relapsed in 90% of cases for a median of 6 times during the follow up period. Cumulative incidence estimates (95% CI) for AKI at 1, 3 and 5 years were 6.2% (0.80-11.3%), 16.7% (7.5-25.0%) and 27.9% (14.9-38.9%), respectively. Age and baseline C-reactive protein were significantly associated with time-to-first AKI event. Six patients underwent a kidney biopsy. Findings included, plasma cell-rich interstitial nephritis (n = 3), neutrophilic-rich interstitial inflammation (n = 1), leukocytoclastic peritubular capillaritis (n = 1), and acute tubular injury (n = 1). AKI responded well to treatment with glucocorticoids but had relapse upon tapering. CONCLUSION: AKI is an underrecognized feature of VEXAS occurring in 25% of patients in this cohort. Age at diagnosis and CRP were associated with time to first AKI event during follow up. Plasma cell-rich interstitial nephritis was the most common histopathologic finding.
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INTRODUCTION: Gelatinous transformation of the bone marrow (GTBM) represents a clinically significant but often underdiagnosed condition, emphasizing the pivotal role of accurate diagnosis in facilitating appropriate treatment strategies. AREAS COVERED: This special report synthesizes insights gathered from a comprehensive appraisal of clinical and pathology publications on GTBM available on PubMed. By employing search terms such as 'gelatinous,' 'gelatinous transformation,' and 'bone marrow,' this report aims to provide a nuanced understanding of GTBM, elucidating distinctive pathological features while distinguishing it from similar pathologies. The review also discusses currently identified causes of GTBM, clinical, imaging, pathologic, and laboratory findings that are associated with GTBM, and treatment options available. EXPERT OPINION: Contrary to popular belief, we suggest that nutrient deficiency is not solely responsible for the pathogenesis of GTBM and that malignancies, infection, and inflammatory conditions play a critical role in its pathogenesis. We propose that further research on the pathophysiology of GTBM should be performed to unravel the complex interplay of nutritional and inflammatory factors in hematopoiesis, paving the way for innovative treatment approaches in hematopoietic disorders. To better facilitate further research in GTBM, we suggest formulating a pooled patient database with nutritional, genetic, and cytokine markers in a prospective fashion.
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Moelle osseuse , Humains , Moelle osseuse/anatomopathologie , Moelle osseuse/métabolismeSujet(s)
Tumeurs du système nerveux , Humains , Femelle , Mâle , Adulte d'âge moyen , Adulte , Sujet âgé , Adolescent , Jeune adulte , Tumeurs du système nerveux/thérapie , Tumeurs du système nerveux/diagnostic , Tumeurs du système nerveux/anatomopathologie , Enfant , Sujet âgé de 80 ans ou plus , Résultat thérapeutique , Enfant d'âge préscolaireSujet(s)
Protéines de fusion bcr-abl , Granulocytes neutrophiles , Humains , Protéines de fusion bcr-abl/génétique , Granulocytes neutrophiles/anatomopathologie , Leucémie myéloïde chronique BCR-ABL positive/diagnostic , Leucémie myéloïde chronique BCR-ABL positive/sang , Leucémie myéloïde chronique BCR-ABL positive/traitement médicamenteux , Leucémie myéloïde chronique BCR-ABL positive/génétique , Mâle , Femelle , Adulte d'âge moyenSujet(s)
Anticorps monoclonaux , Protocoles de polychimiothérapie antinéoplasique , Bortézomib , Cyclophosphamide , Dexaméthasone , Amylose à chaine légère d'immunoglobuline , Humains , Bortézomib/administration et posologie , Bortézomib/usage thérapeutique , Dexaméthasone/administration et posologie , Dexaméthasone/usage thérapeutique , Cyclophosphamide/administration et posologie , Amylose à chaine légère d'immunoglobuline/traitement médicamenteux , Amylose à chaine légère d'immunoglobuline/mortalité , Anticorps monoclonaux/administration et posologie , Anticorps monoclonaux/usage thérapeutique , Protocoles de polychimiothérapie antinéoplasique/usage thérapeutique , Mâle , Femelle , Sujet âgé , Échec thérapeutique , Adulte d'âge moyenRÉSUMÉ
Histiocytic neoplasms are diverse clonal haematopoietic disorders, and clinical disease is mediated by tumorous infiltration as well as uncontrolled systemic inflammation. Individual subtypes include Langerhans cell histiocytosis (LCH), Rosai-Dorfman-Destombes disease (RDD) and Erdheim-Chester disease (ECD), and these have been characterized with respect to clinical phenotypes, driver mutations and treatment paradigms. Less is known about patients with mixed histiocytic neoplasms (MXH), that is two or more coexisting disorders. This international collaboration examined patients with biopsy-proven MXH with respect to component disease subtypes, oncogenic driver mutations and responses to conventional (chemotherapeutic or immunosuppressive) versus targeted (BRAF or MEK inhibitor) therapies. Twenty-seven patients were studied with ECD/LCH (19/27), ECD/RDD (6/27), RDD/LCH (1/27) and ECD/RDD/LCH (1/27). Mutations previously undescribed in MXH were identified, including KRAS, MAP2K2, MAPK3, non-V600-BRAF, RAF1 and a BICD2-BRAF fusion. A repeated-measure generalized estimating equation demonstrated that targeted treatment was statistically significantly (1) more likely to result in a complete response (CR), partial response (PR) or stable disease (SD) (odds ratio [OR]: 17.34, 95% CI: 2.19-137.00, p = 0.007), and (2) less likely to result in progression (OR: 0.08, 95% CI: 0.03-0.23, p < 0.0001). Histiocytic neoplasms represent an entity with underappreciated clinical and molecular diversity, poor responsiveness to conventional therapy and exquisite sensitivity to targeted therapy.
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Maladie d'Erdheim-Chester , Mutation , Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Maladie d'Erdheim-Chester/génétique , Maladie d'Erdheim-Chester/traitement médicamenteux , Sujet âgé , Adolescent , Thérapie moléculaire ciblée , Jeune adulte , Histiocytose à cellules de Langerhans/génétique , Histiocytose à cellules de Langerhans/traitement médicamenteux , Enfant , Histiocytose sinusale cytophagique/génétique , Histiocytose sinusale cytophagique/traitement médicamenteux , Histiocytose sinusale cytophagique/anatomopathologie , Protéines proto-oncogènes B-raf/génétique , Inhibiteurs de protéines kinases/usage thérapeutique , Enfant d'âge préscolaireRÉSUMÉ
Background: Mortality due to immune-mediated thrombotic thrombocytopenic purpura (iTTP) remains significant. Predicting mortality risk may potentially help individualize treatment. The French Thrombotic Microangiopathy (TMA) Reference Score has not been externally validated in the United States. Recent advances in machine learning technology can help analyze large numbers of variables with complex interactions for the development of prediction models. Objectives: To validate the French TMA Reference Score in the United States Thrombotic Microangiopathy (USTMA) iTTP database and subsequently develop a novel mortality prediction tool, the USTMA TTP Mortality Index. Methods: We analyzed variables available at the time of initial presentation, including demographics, symptoms, and laboratory findings. We developed our model using gradient boosting machine, a machine learning ensemble method based on classification trees, implemented in the R package gbm. Results: In our cohort (n = 419), the French score predicted mortality with an area under the receiver operating characteristic curve of 0.63 (95% CI: 0.50-0.77), sensitivity of 0.35, and specificity of 0.84. Our gradient boosting machine model selected 8 variables to predict acute mortality with a cross-validated area under the receiver operating characteristic curve of 0.77 (95% CI: 0.71-0.82). The 2 cutoffs corresponded to sensitivities of 0.64 and 0.50 and specificities of 0.76 and 0.87, respectively. Conclusion: The USTMA Mortality Index was acceptable for predicting mortality due to acute iTTP in the USTMA registry, but not sensitive enough to rule out death. Identifying patients at high risk of iTTP-related mortality may help individualize care and ultimately improve iTTP survival outcomes. Further studies are needed to provide external validation. Our model is one of many recent examples where machine learning models may show promise in clinical prediction tools in healthcare.
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Malignant histiocytosis (MH) is an extremely rare neoplasm of the macrophage-dendritic cell lineage. We report the clinical characteristics, molecular aberrations, treatments, and outcomes of patients with MH seen at two referral centers from January 2000 to May 2023. We identified 43 patients with MH, of which 26 had histiocytic sarcoma (MH-H), 9 interdigitating dendritic cell sarcoma (MH-IDC), and 8 Langerhans cell sarcoma (MH-LC). The median age at diagnosis was 61 years (range, 3-83). Thirty-three patients (77%) had multifocal disease, while 10 had unifocal involvement. Tumor specimens from 22 patients (51%) underwent targeted next generation sequencing, and 19 of 22 (86%) had at least one pathogenic mutation, including mutations in MAPK pathway genes (73%). The median overall survival (OS) among the entire cohort was 16 months (95% CI: 8-50). The outcomes of those with multifocal disease were significantly shorter than their unifocal counterpart: median OS of 10 months versus 50 months (p = .07). Patients with risk organ involvement (bone marrow, spleen, or liver) had significantly inferior outcomes. Chemotherapy and surgery were the most common first-line treatments for multifocal and unifocal disease, respectively. While the outcome for patients with multifocal disease was poor, there was a subset of patients who had durable responses to treatment. Our study highlights that MH has heterogeneous clinical presentation, frequent oncogenic mutations, and prognosis, which is strongly tied to disease extent and type of organ involvement.
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Sarcome histiocytaire , Humains , Enfant d'âge préscolaire , Enfant , Adolescent , Jeune adulte , Adulte , Adulte d'âge moyen , Sujet âgé , Sujet âgé de 80 ans ou plus , Sarcome histiocytaire/génétique , Sarcome histiocytaire/thérapie , Sarcome histiocytaire/anatomopathologie , Macrophages/anatomopathologie , Moelle osseuse/anatomopathologie , Pronostic , Foie/anatomopathologieRÉSUMÉ
ABSTRACT: VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) syndrome, caused by somatic mutations in UBA1, is an autoinflammatory disorder with diverse systemic manifestations. Thrombosis is a prominent clinical feature of VEXAS syndrome. The risk factors and frequency of thrombosis in VEXAS syndrome are not well described, due to the disease's recent discovery and the paucity of large databases. We evaluated 119 patients with VEXAS syndrome for venous and arterial thrombosis and correlated their presence with clinical outcomes and survival. Thrombosis occurred in 49% of patients, mostly venous thromboembolism (VTE; 41%). Almost two-thirds of VTEs were unprovoked, 41% were recurrent, and 20% occurred despite anticoagulation. The cumulative incidence of VTE was 17% at 1 year from symptom onset and 40% by 5 years. Cardiac and pulmonary inflammatory manifestations were associated with time to VTE. M41L was positively associated specifically with pulmonary embolism by univariate (odds ratio [OR]: 4.58, confidence interval [CI] 1.28-16.21, P = .02) and multivariate (OR: 16.94, CI 1.99-144.3, P = .01) logistic regression. The cumulative incidence of arterial thrombosis was 6% at 1 year and 11% at 5 years. The overall survival of the entire patient cohort at median follow-up time of 4.8 years was 88%, and there was no difference in survival between patients with or without thrombosis (P = .8). Patients with VEXAS syndrome are at high risk of VTE; thromboprophylaxis should administered be in high-risk settings unless strongly contraindicated.
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Thrombose , Humains , Mâle , Femelle , Adulte , Adulte d'âge moyen , Thrombose/étiologie , Thrombose/génétique , Thrombose/épidémiologie , Adolescent , Ubiquitin-activating enzymes/génétique , Jeune adulte , Facteurs de risque , Sujet âgé , Enfant , Thrombose veineuse/étiologie , Thrombose veineuse/épidémiologie , Thrombose veineuse/génétique , Incidence , Mutation , Maladies génétiques liées au chromosome X/génétique , Maladies génétiques liées au chromosome X/complications , Enfant d'âge préscolaireRÉSUMÉ
OBJECTIVES: VEXAS syndrome is an adult-onset autoinflammatory disease caused by a somatic pathogenic mutation in the UBA1 (ubiquitin-like modifier activating enzyme 1) gene. Patients present with rheumatologic manifestations and cytopenias and may have an increased predisposition to myelodysplastic syndrome (MDS) and plasma cell neoplasms. Prior studies have reported on the peripheral blood and bone marrow findings in patients with VEXAS syndrome. Due to the protean clinical presentation and lack of specificity of morphologic features (eg, vacuoles in early erythroid and granulocytic precursors), an optimal screening methodology to identify these patients in a timely fashion is desirable. METHODS: To further evaluate and describe the salient diagnostic morphologic features in VEXAS syndrome, we carried out a comprehensive study of the largest single-institution cohort to date. Diagnostic and follow-up bone marrow biopsy specimens from 52 male patients with molecularly identified VEXAS syndrome underwent central review. RESULTS: Cytopenias were common in all cases, primarily macrocytic anemia, monocytopenia, and thrombocytopenia. Bone marrow aspirate and biopsy were often hypercellular, with an increased myeloid/erythroid ratio, granulocytic hyperplasia with left shift, erythroid left shift, and megakaryocyte hyperplasia, which exhibited a range of striking morphologic findings. Distinctly vacuolated myeloid and erythroid precursors were seen in more than 95% of cases. CONCLUSIONS: Our data reveal potential novel diagnostic features, such as a high incidence of monocytopenia and distinct patterns of atypical megakaryopoiesis, that appear different from dysmegakaryopoiesis typically associated with MDS. In our experience, those findings are suggestive of VEXAS, in the appropriate clinical context.
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Moelle osseuse , Humains , Mâle , Adulte d'âge moyen , Moelle osseuse/anatomopathologie , Adulte , Sujet âgé , Études longitudinales , Biopsie , Ubiquitin-activating enzymes/génétique , Syndromes myélodysplasiques/anatomopathologie , Syndromes myélodysplasiques/génétique , Syndromes myélodysplasiques/diagnostic , Jeune adulte , Sujet âgé de 80 ans ou plus , Études de cohortes , Femelle , Mutation , Thrombopénie/anatomopathologie , Thrombopénie/génétiqueRÉSUMÉ
OBJECTIVE: Erdheim-Chester disease (ECD) is rare histiocytosis with a wide range of clinical manifestations. Somatic mutations are key to the pathogenesis of the disease; however, the relationship between germline genetic variants and ECD has not been examined so far. The present study aims to explore the inherited genetic component of ECD by performing the first genome-wide association study. METHODS: After quality controls, a cohort of 255 patients with ECD and 7,471 healthy donors was included in this study. Afterward, a logistic regression followed by in silico functional annotation was performed. RESULTS: A signal at the 18q12.3 genomic region was identified as a new susceptibility locus for ECD (P = 2.75 × 10-11 ; Odds Ratio = 2.09). This association was annotated to the SETBP1 gene, which is involved in clonal haematopoiesis. Functional annotation of this region and of the identified suggestive signals revealed additional genes that could be potentially involved in the pathogenesis of the disease. CONCLUSION: Overall, this work demonstrates that germline genetic variants can impact on the development of ECD and suggests new pathways with a potential pathogenic role.
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Maladie d'Erdheim-Chester , Humains , Maladie d'Erdheim-Chester/génétique , Maladie d'Erdheim-Chester/anatomopathologie , Étude d'association pangénomique , Génomique , Cellules germinales/anatomopathologieRÉSUMÉ
Advances in the treatment of Langerhans cell histiocytosis (LCH) have resulted in a growing survivor population. There is a lack of data on long-term outcomes among adults with LCH. We conducted a retrospective record review of 219 adults (aged ≥18 years) with LCH. Most common presentation was multisystem (34.2%), followed by single-system pulmonary (32%), unifocal (28.3%), and single-system multifocal (5.5%) LCH. Risk organ involvement (the liver, spleen, or bone marrow) was seen in 8.7% of cases, and 40 of 88 (45.5%) tested cases were BRAFV600E. At a median follow-up of 74 months, 5-year progression-free survival (PFS) was 58.3% and estimated median PFS was 83 months. Median overall survival (OS) was not reached; 5- and 10-year OS rates were 88.7% and 74.5%, respectively. Risk organ involvement was associated with worse PFS (hazard ratio [HR], 4.5) and OS (HR, 10.8). BRAFV600E was not associated with risk organ involvement or survival. When compared with matched unaffected US population, individuals with LCH had a significantly higher risk of overall mortality (standardized mortality ratio [SMR], 2.66), specifically among those aged <55 years at diagnosis (SMR, 5.94) and those with multisystem disease (SMR, 4.12). Second cancers occurred in 16.4% cases, including diverse hematologic and solid organ malignancies. LCH-associated deaths constituted 36.1% of deaths and occurred within 5 years of diagnosis. After 5 years, non-LCH causes of death, including second cancers, chronic obstructive pulmonary disease, and cardiovascular diseases, predominated. Our study highlights, to our knowledge, for the first time, that adults with LCH experience early and late mortality from non-LCH causes and the need for development of targeted survivorship programs to improve outcomes.
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Histiocytose à cellules de Langerhans , Seconde tumeur primitive , Tumeurs , Humains , Adulte , Adolescent , Études rétrospectives , Histiocytose à cellules de Langerhans/épidémiologie , RateRÉSUMÉ
INTRODUCTION: Fanconi anemia (FA) is an inherited condition associated with genetic mutations that affect DNA repair proteins. More than 20 genes involved in the FA/BRCA pathway have been implicated in FA, including BRIP1 . Tumefactive brain lesions are rare in FA. CASE REPORT: We describe a patient with FA and recurrent tumefactive brain lesions preceded by calcifications on head computed tomography. A biopsy revealed white-matter gliosis with severe vasculopathy. Whole-genome sequencing demonstrated a BRIP1 homozygous variant with a final diagnosis of recurrent tumefactive brain lesions due to BRIP1 -associated CNS vasculopathy. Immunosuppressive treatment was ineffective in the present case. CONCLUSIONS: Mechanistically, the specific role of BRIP1 mutation in CNS inflammation and vasculopathy is unclear. However, immunodeficiency disorders can lead to autoimmunity and/or immune dysregulation due to the possible loss or gain of function of components of the immune system.
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Anémie de Fanconi , Humains , Anémie de Fanconi/complications , Anémie de Fanconi/génétique , Anémie de Fanconi/anatomopathologie , Mutation/génétique , Système nerveux central/anatomopathologieRÉSUMÉ
In this retrospective study, BRAF mutation status did not correlate with disease extent or (event-free) survival in 156 adults with Langerhans cell histiocytosis. BRAFV600E was associated with an increased incidence of second malignancies, often comprising hematological cancers, which may be clonally related.
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Histiocytose à cellules de Langerhans , Seconde tumeur primitive , Humains , Adulte , Seconde tumeur primitive/épidémiologie , Seconde tumeur primitive/génétique , Protéines proto-oncogènes B-raf/génétique , Études rétrospectives , Incidence , Histiocytose à cellules de Langerhans/épidémiologie , Histiocytose à cellules de Langerhans/génétique , Histiocytose à cellules de Langerhans/anatomopathologie , MutationRÉSUMÉ
Malignant histiocytoses (MHs), or the 'M group' of the Histiocyte Society classification, are characterized by neoplastic histiocytes with large pleomorphic nuclei. MH encompasses the diagnoses of histiocytic sarcoma, interdigitating dendritic cell sarcoma, and Langerhans cell sarcoma. We aimed to define the phenotypic spectrum of MH and examine the genotypic features across this spectrum. Using immunohistochemistry, we arranged the 22 cases into 4 subtypes that correspond to the lines of differentiation from monocytic and dendritic cell precursors as follows: (1) macrophage (n = 5): CD68+, CD163+, CD14+, and Factor 13a+; (2) monocyte-macrophage (n = 5): CD68+, CD163+, CD14+, S100+, and OCT2+; (3) dendritic cell (n = 6): CD68+, CD11c+, S100+, lysozyme+, ZBTB46+, and CD1a/langerin < 5%; and (4) Langerhans cell (n = 6): CD68+, CD11c+, S100+, ZBTB46+, CD1a+, and langerin+. The phenotypic subtypes align with those seen in low-grade histiocytic neoplasms as follows: MH-macrophage type correlates with Erdheim-Chester disease phenotype; MH-monocyte-macrophage type with Rosai-Dorfman disease phenotype, and MH-Langerhans cell type with Langerhans cell histiocytosis. Activating mutations in MAPK-pathway genes were identified in 80% of MH cases; 29% had mutations in the PI3k-AKT-mTOR pathway and 59% had mutations in epigenetic modulating genes. Strong expression of cyclin D1 was present in all cases, whereas p-ERK and p-AKT were not uniformly expressed. Eight of 22 (36%) MH cases were proven to be clonally related to a prior B-cell lymphoma. Defining the phenotypic spectrum of MH provides a guide to diagnosis and allows further exploration into the potential biological and clinical significance.
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Most patients with solitary bone plasmacytomas (SBP) progress to multiple myeloma (MM) after definitive radiation therapy as their primary treatment. Whether the presence of high-risk (HR) cytogenetic abnormalities by fluorescence in situ hybridization (FISH) in the clonal plasma cells, obtained either directly from the diagnostic SBP tissue or the corresponding bone marrow examination at the time of diagnosis, is associated with a shorter time to progression (TTP) to MM is unknown. This study evaluated all patients diagnosed with SBP at the Mayo Clinic from January 2012 to July 2022. The presence of del(17p), t(14;16), t(4;14), or +1q (gain or amplification) by FISH in clonal plasma cells was defined as HR. A total of 114 patients were included in this cohort, and baseline FISH was available for 55 patients (48%), of which 22 were classified as HR (40%). The median TTP to MM for patients with SBP and HR FISH was 8 months (95% confidence interval [CI], 6.3-26) compared with 42 months (95% CI, 25-not reached [NR]) in patients with SBP without HR FISH (P < .001). In a multivariate analysis, only HR FISH was a significant predictor for shorter TTP to MM, independent of minimal marrow involvement and an abnormal serum free light chain ratio at diagnosis. Deletion (17p) and gain 1q abnormalities were the most common FISH abnormalities responsible for the short TTP to MM. Thus, assessing for HR FISH abnormalities in clonal plasma cells derived from either the diagnostic SBP tissue or the staging bone marrow examination of patients with newly diagnosed SBP is feasible and prognostic for a shorter TTP to MM.
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Myélome multiple , Plasmocytome , Humains , Plasmocytome/génétique , Hybridation fluorescente in situ , Aberrations des chromosomes , Myélome multiple/diagnostic , Myélome multiple/génétique , Pronostic , Évolution de la maladieRÉSUMÉ
OBJECTIVES: Understanding of histiocytic disorders has been revolutionized by demonstration of mitogen-activated protein kinase (MAPK) pathway mutations, most commonly BRAFV600E. The optimal testing strategy to assess BRAFV600E is unknown. We aimed to compare performance of testing modalities, to propose a framework for evaluation of BRAFV600E mutation status in histiocytic disorders. METHODS: We retrospectively reviewed patients with histiocytic disorders and BRAF mutation testing on a lesional tissue specimen. RESULTS: In 120 patients, BRAF assessment included immunohistochemistry (IHC) in 97 (80.2%), polymerase chain reaction (PCR) in 35 (28.9%), and next-generation sequencing (NGS) in 62 (51.2%). Forty-five underwent both NGS and IHC. With NGS as the gold standard, the sensitivity and specificity of IHC were 82.4% and 96.4%. Three false negatives were observed in biopsy specimens with low BRAFV600E variant allele frequency or decalcified tissue. One false-positive IHC was observed in a lung biopsy specimen, likely due to antibody cross-reactivity with respiratory cilia. Among 14 with successful NGS and PCR, a single discordance was observed. Two PCR-to-IHC discrepancies were observed, including one other false-positive IHC. CONCLUSIONS: Immunohistochemistry was highly specific for detection of BRAFV600E. Main caveats were false negatives and lack of detection of non-BRAFV600E mutations. We propose the use of IHC as initial screening in general practice with reflex molecular testing if negative.