Castleman disease (CD) describes a group of heterogeneous hematologic disorders with characteristic histopathological features. CD can present with unicentric or multicentric (MCD) regions of lymph ...node enlargement. Some cases of MCD are caused by human herpesvirus-8 (HHV-8), whereas others are HHV-8–negative/idiopathic (iMCD). Treatment of iMCD is challenging, and outcomes can be poor because no uniform treatment guidelines exist, few systematic studies have been conducted, and no agreed upon response criteria have been described. The purpose of this paper is to establish consensus, evidence-based treatment guidelines based on the severity of iMCD to improve outcomes. An international Working Group of 42 experts from 10 countries was convened by the Castleman Disease Collaborative Network to establish consensus guidelines for the management of iMCD based on published literature, review of treatment effectiveness for 344 cases, and expert opinion. The anti–interleukin-6 monoclonal antibody siltuximab (or tocilizumab, if siltuximab is not available) with or without corticosteroids is the preferred first-line therapy for iMCD. In the most severe cases, adjuvant combination chemotherapy is recommended. Additional agents are recommended, tailored by disease severity, as second- and third-line therapies for treatment failures. Response criteria were formulated to facilitate the evaluation of treatment failure or success. These guidelines should help treating physicians to stratify patients based on disease severity in order to select the best available therapeutic option. An international registry for patients with CD (ACCELERATE, #NCT02817997) was established in October 2016 to collect patient outcomes to increase the evidence base for selection of therapies in the future.
Thrombocytopenia, anasarca, fever, reticulin fibrosis, renal insufficiency, and organomegaly (TAFRO) syndrome is a heterogeneous entity manifesting with a constellation of symptoms described above ...that can occur in the context of idiopathic multicentric Castleman disease (iMCD) as well as infectious diseases, malignancies, and rheumatologic disorders. So, iMCD‐TAFRO is an aggressive subtype of iMCD with TAFRO syndrome and often hyper‐vascularized lymph nodes. Since we proposed diagnostic criteria of iMCD‐TAFRO in 2016, we have accumulated new insights on the disorder and additional cases have been reported worldwide. In this systematic review and cohort analysis, we established and validated a definition for iMCD‐TAFRO. First, we searched PubMed and Japan Medical s Society databases using the keyword “TAFRO” to extract cases. Patients with possible systemic autoimmune diseases and hematologic malignancies were excluded. Our search identified 54 cases from 50 articles. We classified cases into three categories: (1) iMCD‐TAFRO (TAFRO syndrome with lymph node histopathology consistent with iMCD), (2) possible iMCD‐TAFRO (TAFRO syndrome with no lymph node biopsy performed and no other co‐morbidities), and (3) TAFRO without iMCD or other co‐morbidities (TAFRO syndrome with lymph node histopathology not consistent with iMCD or other comorbidities). Based on the findings, we propose an international definition requiring four clinical criteria (thrombocytopenia, anasarca, fever/hyperinflammatory status, organomegaly), renal dysfunction or characteristic bone marrow findings, and lymph node features consistent with iMCD. The definition was validated with an external cohort (the ACCELERATE Natural History Registry). The present international definition will facilitate a more precise and comprehensive approach to the diagnosis of iMCD‐TAFRO.
Idiopathic multicentric Castleman disease (iMCD) is a hematologic illness involving cytokine-induced lymphoproliferation, systemic inflammation, cytopenias, and life-threatening multi-organ ...dysfunction. The molecular underpinnings of interleukin-6(IL-6)-blockade refractory patients remain unknown; no targeted therapies exist. In this study, we searched for therapeutic targets in IL-6-blockade refractory iMCD patients with the thrombocytopenia, anasarca, fever/elevated C-reactive protein, reticulin myelofibrosis, renal dysfunction, organomegaly (TAFRO) clinical subtype.
We analyzed tissues and blood samples from three IL-6-blockade refractory iMCD-TAFRO patients. Cytokine panels, quantitative serum proteomics, flow cytometry of PBMCs, and pathway analyses were employed to identify novel therapeutic targets. To confirm elevated mTOR signaling, a candidate therapeutic target from the above assays, immunohistochemistry was performed for phosphorylated S6, a read-out of mTOR activation, in three iMCD lymph node tissue samples and controls. Proteomic, immunophenotypic, and clinical response assessments were performed to quantify the effects of administration of the mTOR inhibitor, sirolimus.
Studies of three IL-6-blockade refractory iMCD cases revealed increased CD8+ T cell activation, VEGF-A, and PI3K/Akt/mTOR pathway activity. Administration of sirolimus significantly attenuated CD8+ T cell activation and decreased VEGF-A levels. Sirolimus induced clinical benefit responses in all three patients with durable and ongoing remissions of 66, 19, and 19 months.
This precision medicine approach identifies PI3K/Akt/mTOR signaling as the first pharmacologically-targetable pathogenic process in IL-6-blockade refractory iMCD. Prospective evaluation of sirolimus in treatment-refractory iMCD is planned (NCT03933904).
Castleman's Awareness & Research Effort/Castleman Disease Collaborative Network, Penn Center for Precision Medicine, University Research Foundation, Intramural NIH funding, and National Heart Lung and Blood Institute.
IMPORTANCE: Questions remain about the role and durability of bariatric surgery for type 2 diabetes mellitus (T2DM). OBJECTIVE: To compare the remission of T2DM following surgical and nonsurgical ...treatments. DESIGN, SETTING, AND PARTICIPANTS: In this 3-arm randomized clinical trial conducted at the University of Pittsburgh Medical Center from October 1, 2009, to June 26, 2014, in Pittsburgh, Pennsylvania, outcomes were assessed 3 years after treating 61 obese participants aged 25 to 55 years with T2DM. Analysis was conducted with an intent-to-treat population. INTERVENTIONS: Participants were randomized to either an intensive lifestyle weight loss intervention for 1 year followed by a low-level lifestyle intervention for 2 years or surgical treatments (Roux-en-Y gastric bypass RYGB or laparoscopic adjustable gastric banding LAGB) followed by low-level lifestyle intervention in years 2 and 3. MAIN OUTCOMES AND MEASURES: Primary end points were partial and complete T2DM remission and secondary end points included diabetes medications and weight change. RESULTS: Body mass index (calculated as weight in kilograms divided by height in meters squared) was less than 35 for 26 participants (43%), 50 (82%) were women, and 13 (21%) were African American. Mean (SD) values were 100.5 (13.7) kg for weight, 47.3 (6.6) years for age, 7.8% (1.9%) for hemoglobin A1c level, and 171.3 (72.5) mg/dL for fasting plasma glucose level. Partial or complete T2DM remission was achieved by 40% (n = 8) of RYGB, 29% (n = 6) of LAGB, and no intensive lifestyle weight loss intervention participants (P = .004). The use of diabetes medications was reduced more in the surgical groups than the lifestyle intervention–alone group, with 65% of RYGB, 33% of LAGB, and none of the intensive lifestyle weight loss intervention participants going from using insulin or oral medication at baseline to no medication at year 3 (P < .001). Mean (SE) reductions in percentage of body weight at 3 years were the greatest after RYGB at 25.0% (2.0%), followed by LAGB at 15.0% (2.0%) and lifestyle treatment at 5.7% (2.4%) (P < .01). CONCLUSIONS AND RELEVANCE: Among obese participants with T2DM, bariatric surgery with 2 years of an adjunctive low-level lifestyle intervention resulted in more disease remission than did lifestyle intervention alone. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01047735
Idiopathic multicentric Castleman disease (iMCD) is a rare and poorly-understood cytokine storm-driven inflammatory disorder. Interleukin-6 (IL-6) is a known disease driver in some patients, but ...anti-IL-6 therapy with siltuximab is not effective in all patients, and biomarkers indicating success at an early time point following treatment initiation are lacking. Here we show, by comparison of levels of 1,178 proteins in sera of healthy participants (N = 42), patients with iMCD (N = 88), and with related diseases (N = 60), a comprehensive landscape of candidate disease mediators and predictors of siltuximab response. C-X-C Motif Chemokine Ligand-13 (CXCL13) is identified and validated as the protein most prominently up-regulated in iMCD. Early and significant decrease in CXCL13 levels clearly distinguishes siltuximab responders from non-responders; a 17% reduction by day 8 following siltuximab therapy initiation is predictive of response at later time points. Our study thus suggests that CXCL13 is a predictive biomarker of response to siltuximab in iMCD.
Idiopathic multicentric Castleman disease (iMCD) is a rare and poorly understood hematologic disorder characterized by lymphadenopathy, systemic inflammation, cytopenias, and life-threatening ...multiorgan dysfunction. Interleukin-6 (IL-6) inhibition effectively treats approximately one-third of patients. Limited options exist for nonresponders, because the etiology, dysregulated cell types, and signaling pathways are unknown. We previously reported 3 anti-IL-6 nonresponders with increased mTOR activation who responded to mTOR inhibition with sirolimus. We investigated mTOR signaling in tissue and serum proteomes from iMCD patients and controls. mTOR activation was increased in the interfollicular space of iMCD lymph nodes (N = 26) compared with control lymph nodes by immunohistochemistry (IHC) for pS6, p4EBP1, and p70S6K, known effectors and readouts of mTORC1 activation. IHC for pS6 also revealed increased mTOR activation in iMCD compared with Hodgkin lymphoma, systemic lupus erythematosus, and reactive lymph nodes, suggesting that the mTOR activation in iMCD is not just a product of lymphoproliferation/inflammatory lymphadenopathy. Further, the degree of mTOR activation in iMCD was comparable to autoimmune lymphoproliferative syndrome, a disease driven by mTOR hyperactivation that responds to sirolimus treatment. Gene set enrichment analysis of serum proteomic data from iMCD patients (n = 88) and controls (n = 42) showed significantly enriched mTORC1 signaling. Finally, functional studies revealed increased baseline mTOR pathway activation in peripheral monocytes and T cells from iMCD remission samples compared with healthy controls. IL-6 stimulation augmented mTOR activation in iMCD patients, which was abrogated with JAK1/2 inhibition. These findings support mTOR activation as a novel therapeutic target for iMCD, which is being investigated through a trial of sirolimus (NCT03933904).
•The mTOR pathway is hyperactivated in iMCD and a candidate novel therapeutic target.•mTOR activation is increased in iMCD to a similar extent as the mTOR-driven autoimmune lymphoproliferative syndrome.
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Human Herpesvirus‐8 (HHV‐8)‐negative/idiopathic multicentric Castleman disease (iMCD) is a poorly understood disease involving polyclonal lymphoproliferation with dysmorphic germinal centers, ...constitutional symptoms, and multi‐organ failure. Patients can experience thrombocytopenia, anasarca, reticulin fibrosis, renal dysfunction, organomegaly, and normal immunoglobulin levels, – iMCD‐TAFRO. Others experience thrombocytosis, milder effusions, and hypergammaglobulinemia, –iMCD‐Not Otherwise Specified (iMCD‐NOS). Though the etiology is unknown in both subtypes, iMCD symptoms and disease progression are believed to be driven by a cytokine storm, often including interleukin‐6 (IL‐6). However, approximately two‐thirds of patients do not respond to anti‐IL‐6 therapy; alternative drivers and signaling pathways are not known for anti‐IL‐6 nonresponders. To identify potential mediators of iMCD pathogenesis, we quantified 1129 proteins in 13 plasma samples from six iMCD patients during flare and remission. The acute phase reactant NPS‐PLA2 was the only significantly increased protein (P = .017); chemokines and complement were significantly enriched pathways. Chemokines represented the greatest proportion of upregulated cytokines, suggesting that iMCD involves a chemokine storm. The chemokine CXCL13, which is essential in homing B cells to germinal centers, was the most upregulated cytokine across all patients (log2 fold‐change = 3.22). Expression of CXCL13 was also significantly increased in iMCD lymph node germinal centers compared to controls in a stromal meshwork pattern. We observed distinct proteomic profiles between the two iMCD‐TAFRO patients, who both failed anti‐IL‐6‐therapy, and the four iMCD‐NOS patients, in whom all three treated with anti‐IL‐6‐therapy responded, suggesting that differing mechanisms may exist. This study reveals proteomic differences between flare and remission and the potential to molecularly define iMCD subgroups.
Idiopathic multicentric Castleman disease (iMCD) is a rare hematologic disorder with heterogeneous presentations ranging from moderate constitutional symptoms to life-threatening multiorgan system ...involvement. iMCD patients present with vastly different clinical subtypes, with some patients demonstrating thrombocytopenia, anasarca, fever/elevated C-reactive protein, reticulin fibrosis/renal failure, and organomegaly (TAFRO) and others demonstrating more mild/moderate symptoms with potential for severe disease (not otherwise specified, NOS). Due to its rarity and heterogeneity, the natural history and long-term burden of iMCD are poorly understood. We investigated real-world medical data from ACCELERATE, a large natural history registry of Castleman disease patients, to better characterize the long-term disease burden experienced by these patients. We found that iMCD-TAFRO patients face significant hospitalization burden, requiring more time in the hospital than iMCD-NOS patients during the year surrounding diagnosis (median IQR 36 18, 61 days vs. 0 0, 4 days; p.
Castleman disease (CD) includes a group of rare and heterogeneous disorders with characteristic lymph node histopathological abnormalities. CD can occur in a single lymph node station, which is ...referred to as unicentric CD (UCD). CD can also involve multicentric lymphadenopathy and inflammatory symptoms (multicentric CD MCD). MCD includes human herpesvirus-8 (HHV-8)–associated MCD, POEMS-associated MCD, and HHV-8−/idiopathic MCD (iMCD). The first-ever diagnostic and treatment guidelines were recently developed for iMCD by an international expert consortium convened by the Castleman Disease Collaborative Network (CDCN). The focus of this report is to establish similar guidelines for the management of UCD. To this purpose, an international working group of 42 experts from 10 countries was convened to establish consensus recommendations based on review of treatment in published cases of UCD, the CDCN ACCELERATE registry, and expert opinion. Complete surgical resection is often curative and is therefore the preferred first-line therapy, if possible. The management of unresectable UCD is more challenging. Existing evidence supports that asymptomatic unresectable UCD may be observed. The anti–interleukin-6 monoclonal antibody siltuximab should be considered for unresectable UCD patients with an inflammatory syndrome. Unresectable UCD that is symptomatic as a result of compression of vital neighboring structures may be rendered amenable to resection by medical therapy (eg, rituximab, steroids), radiotherapy, or embolization. Further research is needed in UCD patients with persisting constitutional symptoms despite complete excision and normal laboratory markers. We hope that these guidelines will improve outcomes in UCD and help treating physicians decide the best therapeutic approach for their patients.
•The preferred therapy for UCD is complete surgical resection.•Unresectable asymptomatic UCD may be observed; symptomatic UCD requires rituximab ± steroids or anti–interleukin-6 antibody.
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Summary
Siltuximab is the only US Food and Drug Administration‐approved treatment for idiopathic multicentric Castleman disease (iMCD), a rare haematological disorder associated with substantial ...morbidity and mortality. Although siltuximab induces a response in a significant proportion of iMCD patients via interleukin 6 (IL6) neutralization, it is not universally effective. To develop a predictive model of response, we performed an in‐depth analysis of 38 baseline laboratory parameters in iMCD patients from the phase II siltuximab trial who met criteria for treatment response or treatment failure. Univariate analyses identified eight baseline laboratory parameters that were significantly different between responders and treatment failures: albumin, immunoglobulin G (IgG), immunoglobulin A, C reactive protein (CRP), fibrinogen, haemoglobin, sodium and triglycerides. Stepwise logistic regression analysis of these candidate parameters identified a top performing model that included fibrinogen, IgG, haemoglobin and CRP. Based on cross‐validation of the final multivariate logistic regression model, the model accurately discriminated responders from those who failed treatment (area under the receiver operator characteristic curve 0·86, 95% confidence interval: 0·73–0·95). All four laboratory parameters associated with response to siltuximab have biological relationships with IL6 and acute inflammation. Our model suggests that iMCD patients with laboratory evidence of an inflammatory syndrome are the best candidates for siltuximab therapy.