Castleman disease in pediatrics: Insights on presentation, treatment, and outcomes from a two-site retrospective cohort study

The clinical picture of Castleman disease: a systematic review and meta-analysis

ABSTRACT

Castleman disease (CD) encompasses a spectrum of rare disorders, including unicentric CD (UCD), idiopathic multicentric CD (iMCD), and human herpesvirus 8-associated MCD (HHV8+ MCD). We performed a systematic review of publications reporting ≥5 cases of CD between 1995 and 2021, following preferred reporting items for systematic reviews and meta-analyses guidelines, to describe and compare subtypes. We extracted data on clinical symptoms and laboratory parameters as stated in international consensus diagnostic criteria for iMCD and estimated the frequency of each criterion using meta-analyses. We analyzed 32 studies describing 559 UCD, 1023 iMCD, and 416 HHV8+ MCD cases. Although many symptoms and laboratory abnormalities occurred at similar rates in patients with iMCD and HHV8+ MCD, patients with HHV8+ MCD had significantly higher rates of constitutional symptoms (46.6% vs 98.6%; P = .038) and splenomegaly (48.2% vs 89.2%; P = .031). Renal dysfunction was significantly more common in patients with iMCD than in patients with HHV8+ MCD before adjustment (36.9% vs 17.4%; P = .04; adjusted P = .1). Patients with UCD had lower rates of symptoms and laboratory abnormalities, although these were present in 20% of patients and were particularly pronounced in pediatric UCD. There are many similarities in the symptomatology of iMCD and HHV8+ MCD; many patients experience constitutional symptoms and organ dysfunction. Differences between these subtypes likely reflect differences in pathophysiology and/or comorbidity burdens.

A hypothesis on treatment strategy of severe multicentric Castleman disease with continuous renal replacement therapy

Castleman disease (CD) is a rare lymphoproliferative disorder, with non-specific clinical manifestations, often delayed diagnosis and treatment, which pose a significant challenge in the present times. Patients diagnosed with this disease have poor prognosis due to the limited treatment options. Multicentric CD occurs at multiple lymph node stations and is associated with a proinflammatory response that leads to the development of the so-called 'B symptoms'. IL-6 seems to be a key cytokine involved in various manifestations such as lymphadenopathies, hepatosplenomegaly, and polyclonal hypergammaglobulinemia. Its levels correlate with the activity of the disease. Other consequences of MCD include increased fibrinogen levels leading to deep vein thrombosis and thromboembolic disorders, high hepcidin levels causing anaemia, elevated VEGF levels promoting angiogenesis and vascular permeability, which, along with hypoalbuminemia, induce oedema, ascites, pleural and pericardial effusions, and in severe cases, generalized anasarca. In extreme cases multiple organ failure can occur, often resulting in death. We propose the use of continuous renal replacement therapy (CRRT) in managing severe multicentric CD. Our arguments are based on the principles that CRRT is able to remove IL-6 from circulation thus attenuating the cytokine storm, can influence hepcidin levels, and reduction in oedema, and is often used in multiple organ failure to regain homeostasis control. Therefore, it could be used as a therapy or bridge therapy in severe cases. To sustain our hypothesis with evidence, we have gathered several studies from the literature confirming the successful removal of cytokines, especially IL-6 from circulation, which can be used as a starting point.

Castleman Disease Presenting in the Neck: A Report of 3 Cases and a Literature Review

BACKGROUND Castleman's disease (CD) is a reactive lymph node hyperplasia initially identified by Castleman in 1956. CD predominantly affects individuals 20-50 years of age, with low incidence in children. This case report describes 3 cases of CD treated in our hospital and reviews the relevant literature. The purpose of this case report was to enhance clinical understanding and treatment of CD in the head and neck in children. CASE REPORT To enhance clinical understanding and improve treatment of CD in the head and neck region in children, we present the cases of 3 patients who were admitted to the hospital, primarily presenting with a neck mass. Preoperatively, the patients collectively exhibited non-specific findings. Surgical interventions were performed with Cases 1 and 3 undergoing left functional (radical) neck lymph node dissection, in contrast to Case 2, in which bilateral functional (radical) neck lymph node dissection was executed. Pathological examination confirmed the diagnosis of CD in each of the 3 patients. Following surgery, a follow-up period ranging from 3 months to 1 year revealed that all patients had successfully recovered, with no recurrence. CONCLUSIONS Castleman disease is a rare disease in children and difficult clinical diagnosis. Some patients with unicentric Castleman disease (UCD) can be treated with surgery, and those with multicentric Castleman disease (MCD) need chemotherapy, but at present there is no widely accepted treatment plan.

Clinical features and treatment outcomes of Castleman disease in children: a retrospective cohort in China

Castleman disease (CD) is a rare lymphoproliferative disorder of undetermined etiology. Unicentric CD (UCD) and multicentric CD (MCD) are two phenotypes of CD diagnosed by the histopathology of lymph nodes. We attempted to describe a pediatric CD cohort to optimize the management of this disease. We reviewed the medical records of pediatric patients diagnosed with CD between April, 2004, and October, 2022, at the Children's Hospital of Fudan University. Prognosis information was collected in January, 2023, by telephone inquiry. Twenty-two patients with UCD and 2 patients with MCD were identified, all with hyaline vascular (HV) type. The median ages at diagnosis were 10.75 years (IQR 8, 12.81) for UCD and 14.42 years (IQR 13.42, 15.42) for MCD. The most common lesion location of UCD was the neck (9/22, 40.91%) and abdomen (9/22, 40.91%). Systematic symptoms occurred on 10/22 (45.45%) patients with UCD and 1/2 (50%) patients with MCD, and abnormal laboratory indexes were detected in both. Resection and biopsy were performed on all patients. One out of two patients with MCD also received rituximab for upfront therapy. After a median of 4 years (IQR 1.5, 6) of follow-up time, the overall survival was 100% and the complete remission rate in UCD was 63%. There was no relapse or progression.

CONCLUSIONS

Our series demonstrated that HV-UCD was the most common type in children. Resection and biopsy were used for both deterministic diagnoses and treatments. Despite the high possibility to develop systematic inflammation, children with CD showed promising outcomes.

WHAT IS KNOWN

• Castleman disease is a rare lymphoproliferative disorder with limited cohort studies, especially in pediatrics. • The ubiquity of delayed confirmations and misdiagnoses points to a lack of knowledge about etiology and characteristics, which is a prerequisite for novel therapeutics.

WHAT IS NEW

• We retrospectively reviewed and analyzed the clinical and pathological symptoms, laboratory and imaging features, and treatment outcomes of a Chinese pediatric cohort with Castleman disease. • Our work may improve the recognition and optimize the management of this rare disease in children.

Castleman Disease of the Parapharyngeal Space in a Pediatric Patient: A Case Report

The Castleman Disease (CD), also recognized as giant lymph node hyperplasia or vascular follicular lymphoid hyperplasia, is an infrequent lymphoproliferative disorder with substantial clinical variability. Parapharyngeal location of this disease is very rare and in pediatric population it is even rarer. This article presents a case of Unicentric CD (hyaline vascular type) in an 8-year-old female, where the disease was localized within the parapharyngeal space. Clinical manifestations were limited to the presence of a local mass, with no other specific symptoms observed. Laboratory assessments revealed no significant abnormalities. She underwent surgery using a cervical-parotid approach and experienced a good postoperative recovery. Histopathological analysis confirmed the diagnosis. This case underscores the need for a comprehensive evaluation and consideration of uncommon etiologies in the assessment of parapharyngeal masses, even in pediatric patients.

Hyperglycemia and Other Glycemic Measures Throughout Therapy for Pediatric Acute Lymphoblastic Leukemia and Lymphoma

Transient hyperglycemia during induction chemotherapy is associated with increased morbidity and mortality in patients with acute lymphoblastic leukemia (ALL). Treatment with glucocorticoids, asparaginase, and stress are the proposed causal factors. Although these risks are not exclusive to induction, glycemic control throughout the remainder of ALL/lymphoma (ALL/ALLy) therapy has not been described. Furthermore, prior research has been limited to transient hyperglycemia. This study aimed to characterize glycemic control throughout ALL/ALLy and to evaluate risk factors and outcomes associated with increased mean glucose and glucose coefficient of variation (glucose CV) during induction chemotherapy. The records for 220 pediatric/young adult patients, age 1 to 26 years, who underwent treatment for ALL/ALLy from 2010 to 2014 at Children's Hospital Colorado were retrospectively reviewed. Measures of glycemic control were calculated for each cycle. For the cycle with the highest mean glucose, induction (n=208), multivariable models were performed to identify potential risk factors and consequences of increased glucose. Highest mean glucose by cycle were induction 116 mg/dL, pretreatment 108 mg/dL, delayed intensification 96 mg/dL, and maintenance 93 mg/dL; these cycles also had the most glycemic variability. During induction, patients with Down syndrome, or who were ≥12 years and overweight/obese, had higher mean glucoses; age and overweight/obese status were each associated with increased glucose CV. In multivariable analysis, neither induction mean glucose nor glucose CV were associated with increased hazard of infection, relapse, or death.

[Castleman disease]

The term "Castleman disease" covers a variety of entities that have very different clinical, biological, pathological and physiopathological features. In this issue, we review the characteristics of the unicentric Castleman disease, of the HHV8 associated multicentric Castleman disease and the idiopathic multicentric Castleman disease associated or not with TAFRO syndrome ("thrombocytopenia, anasarca, fever, reticulin myelofibrosis and/or renal insufficiency, organomegaly"). We detail the differential diagnostics of these entities.

Off-label use of canakinumab in pediatric rheumatology and rare diseases

Since the first success of interleukin-1 blockade in cryopyrin-associated periodic syndrome, the use of interleukin-1 inhibitors has expanded to other disorders, including off-label indications. In particular, canakinumab has been employed in an off-label fashion in several diseases such as rare monogenic autoinflammatory diseases and multifactorial autoinflammatory diseases, disclosing an excellent efficacy and good safety profile in pediatric patients unresponsive to standards of care. In addition, hyperferritinemic syndromes and complex disorders, as well as Kawasaki disease, uveitis, and other pediatric rare disorders, represent additional areas where canakinumab efficacy is worth exploring. Altogether, the results summarized below are of paramount importance in pediatric patients where a considerable proportion of treatments are prescribed off-label. This review focuses on the off-label use of canakinumab in pediatric patients affected by systemic immune-mediated diseases.

Imaging evaluation of the pediatric mediastinum: new International Thymic Malignancy Interest Group classification system for children

Mediastinal masses are commonly identified in the pediatric population with cross-sectional imaging central to the diagnosis and management of these lesions. With greater anatomical definition afforded by cross-sectional imaging, classification of mediastinal masses into the traditional anterior, middle and posterior mediastinal compartments - as based on the lateral chest radiograph - has diminishing application. In recent years, the International Thymic Malignancy Interest Group (ITMIG) classification system of mediastinal masses, which is cross-sectionally based, has garnered acceptance by multiple thoracic societies and been applied in adults. Therefore, there is a need for pediatric radiologists to clearly understand the ITMIG classification system and how it applies to the pediatric population. The main purpose of this article is to provide an updated review of common pediatric mediastinal masses and mediastinal manifestations of systemic disease processes in the pediatric population based on the new ITMIG classification system.

Pediatric mediastinal masses

Mediastinal masses are categorized based on the International Thymic Malignancy Interest Group (ITMIG) classification into prevascular, visceral and paravertebral compartments. The schema is based on cross-sectional imaging, mainly CT, and helps with generating a differential diagnosis based on location of the mass. Up to half of all pediatric mediastinal tumors are malignant. In this review we describe mediastinal masses that are relevant to the pediatric population, as well as the role of MR imaging of mediastinal masses and its advantages.

Transcriptome and unique cytokine microenvironment of Castleman disease

Castleman disease (CD) represents a group of rare, heterogeneous and poorly understood disorders that share characteristic histopathological features. Unicentric CD (UCD) typically involves a single enlarged lymph node whereas multicentric CD (MCD) involves multiple lymph node stations. To understand the cellular basis of CD, we undertook a multi-platform analysis using targeted RNA sequencing, RNA in-situ hybridization (ISH), and adaptive immune receptor rearrangements (AIRR) profiling of archived tissue from 26 UCD, 14 MCD, and 31 non-CD reactive controls. UCD showed differential expression and upregulation of follicular dendritic cell markers (CXCL13, clusterin), angiogenesis factors (LPL, DLL4), extracellular matrix remodeling factors (TGFβ, SKIL, LOXL1, IL-1β, ADAM33, CLEC4A), complement components (C3, CR2) and germinal center activation markers (ZDHHC2 and BLK) compared to controls. MCD showed upregulation of IL-6 (IL-6ST, OSMR and LIFR), IL-2, plasma cell differentiation (XBP1), FDC marker (CXCL13, clusterin), fibroblastic reticular cell cytokine (CCL21), angiogenesis factor (VEGF), and mTORC1 pathway genes compared to UCD and controls. ISH studies demonstrated that VEGF was increased in the follicular dendritic cell-predominant atretic follicles and the interfollicular macrophages of MCD compared to UCD and controls. IL-6 expression was higher along interfollicular vasculature-associated cells of MCD. Immune repertoire analysis revealed oligoclonal expansions of T-cell populations in MCD cases (2/6) and UCD cases (1/9) that are consistent with antigen-driven T cell activation. The findings highlight the unique genes, pathways and cell types involved in UCD and MCD. We identify potential novel targets in CD that may be harnessed for therapeutics.

Idiopathic multicentric Castleman disease with TAFRO clinical subtype responsive to IL-6/JAK inhibition: A pediatric case series

TAFRO (thrombocytopenia, anasarca, fever/elevated C-reactive protein, reticulin myelofibrosis, renal dysfunction, and organomegaly) clinical subtype of idiopathic multicentric Castleman disease (iMCD-TAFRO) is a rare lymphoproliferative disease characterized by systemic inflammation. First-line treatment for iMCD-TAFRO includes steroids and interleukin (IL)-6 blockade. Many patients have refractory disease, which is associated with significant morbidity and mortality, and treatment remains challenging. We present two pediatric cases of iMCD-TAFRO. One patient responded to IL-6 blockade; the other was refractory to siltuximab and chemotherapy, ultimately responding to JAK inhibition with ruxolitinib. This is the first reported pediatric case of refractory iMCD-TAFRO responding to JAK inhibition.

Mediastinal Masses in Children: Radiologic-Pathologic Correlation

Most pediatric masses in the chest are located in the mediastinum. These masses are often initially detected incidentally on chest radiographs in asymptomatic children, although some patients may present with respiratory symptoms. At chest radiography, the mediastinum has been anatomically divided into anterior, middle, and posterior compartments. However, with the International Thymic Malignancy Interest Group classification scheme, which is based on cross-sectional imaging findings, the mediastinum is divided into prevascular, visceral, and paravertebral compartments. In the prevascular compartment, tumors of thymic origin, lymphomas, germ cell tumors, and vascular tumors are encountered. In the visceral compartment, lymphadenopathy and masses related to the foregut are seen. In the paravertebral compartment, neurogenic tumors are most common. Using the anatomic location in combination with knowledge of the imaging and pathologic features of pediatric mediastinal masses aids in accurate diagnosis of these masses to guide treatment and management decisions. An invited commentary by Lee and Winant is available online. ^©RSNA, 2021.

International evidence-based consensus diagnostic and treatment guidelines for unicentric Castleman disease

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.

Pediatric Lymphoid and Histiocytic Lesions in the Head and Neck

Lymphoid and histiocytic lesions of the head and neck in pediatric patients is a fascinating topic as most of these lesions are benign, but that the neoplastic cases are essential to diagnose accurately for appropriate treatment. It is thought that 90% of children will have palpable lymph nodes between the ages of 4 to 8; most, but not all, are non-malignant and some resolve spontaneously without treatment. This paper will look at many of the benign and malignant lesions of both lymphocytic and histiocytic origin that present in the head and neck of children focusing on their diagnostic criteria. There is a very pertinent discussion of nonmalignant lymphoid proliferations, as infections and other reactive conditions dominate the pathology of pediatric lymphohistiocytic head and neck lesions. Discussion of those lymphomas which arise more frequently in the head and neck focuses on those seen in children and young adults such as classic Hodgkin lymphoma and Burkitt lymphoma, as well as new more controversial entities such as pediatric-type follicular lymphoma. Histiocytic lesions, both benign and malignant, are described and may be challenging to diagnose.

Histologic and Laboratory Characteristics of Symptomatic and Asymptomatic Castleman Disease in the Pediatric Population

OBJECTIVES

Compare the morphologic, laboratory, and clinical features of asymptomatic and symptomatic Castleman disease in the pediatric population.

METHODS

We reviewed clinical records and histopathology of patients with Castleman disease from 2 pediatric institutions.

RESULTS

Of 39 patients with pediatric Castleman disease, 37 had unicentric disease, all classified with the hyaline vascular variant of Castleman disease, 8 of which were clinically symptomatic. These 8 patients demonstrated abnormal laboratory findings, including microcytic anemia, elevated erythrocyte sedimentation rate and C-reactive protein, and hypoalbuminemia. In addition, histopathologic evaluation showed that the 8 symptomatic cases had more hyperplastic germinal centers, fewer atrophic or regressed germinal centers, fewer mantle zones containing multiple germinal centers, reduced "onion skinning" of mantle zones, and fewer "lollipop" formations compared with the asymptomatic cases.

CONCLUSIONS

This series of pediatric Castleman disease showed that lymph nodes from asymptomatic patients generally demonstrated the more classic hyaline vascular histology, whereas those with symptoms could lack or have only focal classic findings. As such, reactive lymph nodes with subtle Castleman-like features should prompt clinical correlation to ensure proper diagnosis.

The French paediatric cohort of Castleman disease: a retrospective report of 23 patients

BACKGROUND

Castleman disease (CD) is a rare non-malignant lymphoproliferation of undetermined origin. Two major disease phenotypes can be distinguished: unicentric CD (UCD) and multicentric CD (MCD). Diagnosis confirmation is based on histopathological findings in a lymph node. We attempted to survey all cases of paediatric CD identified to date in France to set up a national registry aiming to improve CD early recognition, treatment and follow-up, within the context of a new national reference center (http://www.castleman.fr).

METHODS

In 2016, we e-mailed a questionnaire to members of the French paediatric immunohaematology society, the paediatric rheumatology society and the Reference Centre for Castleman Disease to retrospectively collect cases of paediatric CD (first symptoms before age 18 years). Anatomopathological confirmation was mandatory.

RESULTS

We identified 23 patients (12 girls) with a diagnosis of UCD (n = 17) and MCD (n = 6) between 1994 and 2018. The mean age at first symptoms was 11.47 ± 4.23 years for UCD and 8.3 ± 3.4 years for MCD. The mean diagnosis delay was 8.16 ± 10.32 months for UCD and 5.16 ± 5.81 years for MCD. In UCD, the initial symptoms were isolated lymph nodes (n = 10) or lymph node associated with other symptoms (n = 7); fever was present in 3 patients. Five patients with MCD presented fever. No patients had HIV or human herpesvirus 8 infection. Autoinflammatory gene mutations were investigated in five patients. One patient with MCD carried a K695R heterozygous mutation in MEFV, another patient with MCD and Duchenne myopathy carried two variants in TNFRSF1A and one patient with UCD and fever episodes carried two heterozygous mutations, in IL10RA and IL36RN, respectively. Treatment of UCD was mainly surgical resection, steroids, and radiotherapy. Treatment of MCD included tocilizumab, rituximab, anakinra, steroids, chemotherapy, and splenectomy. Overall survival after a mean of 6.1 ± 6.4 years of follow-up, was 100% for both forms.

CONCLUSION

Paediatric CD still seems underdiagnosed, with a significant diagnosis delay, especially for MCD, but new international criteria will help in the future. Unlike adult CD, which is strongly associated with HIV and human herpesvirus 8 infection, paediatric CD could be favored by primary activation of innate immunity and may affect life expectancy less.

Unicentric Castleman Disease Mimicking an Autoinflammatory Disorder: A Diagnostic Challenge in a Pediatric Patient With Recurrent Fever

Unicentric Castleman disease (CD) is a rare lymphoproliferative disorder that is characterized by the enlargement of lymph nodes on the neck, mediastinum, and retroperitoneum. Herein, we present a 6-year-old female patient, referred to our medical center because of recurrent fever accompanied by cervical lymphadenopathy and elevated inflammatory markers since 3 years of age. Fever episodes lasting 1 day continued irregularly without any accompanying symptom. MEditerranean FeVer (MEFV) gene analysis showed no mutations; however, as inflammatory markers including serum amyloid A remained markedly high during attack-free periods, colchicines was initiated. The patient did not respond to maximally tolerated doses of colchicine; therefore, we added canakinumab and systemic methylprednisolone, subsequently. Unresponsiveness to 3 doses of bimonthly canakinumab and new-onset hepatosplenomegaly led us to investigate large-vessel vasculitis and malignancy; therefore, we performed Position emission tomography, which further revealed a hypermetabolic retroperitoneal solid mass. After performing the excisional biopsy, the patient has been diagnosed as suffering from hyaline vascular variant CD, confirmed by histopathology. In conclusion, we report a pediatric unicentric CD, which resembled autoinflammatory diseases and responded well to surgical resection, with the normalization of inflammatory markers 1 month after the procedure. CD, even the unicentric and hyaline vascular variant, should be considered in the differential diagnosis of the patients with an autoinflammatory phenotype.