Enfermedad de Castleman, fisiopatología, avances en el diagnóstico y tratamiento / Castleman's disease, pathophysiology, advances in diagnosis and treatment

La enfermedad de Castleman (EC) engloba a un conjunto heterogéneo de procesos linfoproliferativos que comparten rasgos histológicos bien definidos. Se considera una enfermedad rara o minoritaria u su incidencia no es del todo conocida, aunque se estima en menos de uno por cada 100.000 habitantes. Tiene una distribución bimodal (30-40 años y luego los 60-80 años). Su incidencia es similar en ambos sexos, aunque la variante unicéntrica parece tener ligero predominio en mujeres con proporción 2:1. La EC se clasifica en una forma hialinovascular (siendo esta la más frecuente) y otra plasmocelular, relacionadas con el virus de la inmunodeficiencia humana (VIH) y el virus herpes humano tipo 8 (VHH-8), que junto a otros mecanismos autoinmunitarios desarrollan la hiperproducción de interleucina-6 (IL-6) por parte de los linfocitos B. Existen diferentes líneas de tratamiento, donde destaca el uso de anti IL-6, siendo el siltuximab el más utilizado y catalogado como el fármaco huérfano de esta patología.(AU)

Castleman's disease (CD) encompasses a heterogeneous set of reactive lymphoproliferative processes that share well-defined histologic features. CD is considered a rare or minority disease. The incidence of CD is not fully known, although it is estimated at less than 1 per 100,000 inhabitants. It has a bimodal distribution (30–40 years and then 60–80 years). The incidence is similar in both sexes, although the unicentric variant seems to have a slight predominance in women with a 2:1 ratio. CD is classified into a hyalinovascular form (this being the most frequent) and a plasmocellular form, related to the HIV and VHH-8 viruses, which together with other autoimmune mechanisms develop hyperproduction of interleukin-6 (IL-6) by B lymphocytes. There are different lines of treatment, where the use of anti IL-6 stands out, being siltuximab the most used as orphan drug in this pathology.(AU)

TAFRO Syndrome with Renal Thrombotic Microangiopathy: Insights into the Molecular Mechanism and Treatment Opportunities.

TAFRO syndrome is an extremely rare form of idiopathic MCD, characterized by thrombocytopenia, anasarca, fever, reticulin fibrosis on bone marrow biopsy, and organomegaly. Like idiopathic MCD, renal involvement is also a common presentation in patients with TAFRO syndrome. Furthermore, membranoproliferative glomerulonephritis (MPGN)-like injury and thrombotic microangiopathy (TMA) are the most reported histopathologic findings of renal biopsy. Several molecular mechanisms have been previously postulated in order to explain the TAFRO syndrome symptoms, including abnormal production of interleukin-6 (IL-6), vascular endothelial growth factor (VEGF), etc. The role of these cytokines in renal injury, however, is not well understood. The aim of this review article is to summarize the latest knowledge of molecular mechanisms behind the TAFRO syndrome and their potential role in renal damage.

Unexplained cause of thrombocytopenia, fever, anasarca and hypothyroidism: TAFRO syndrome with thrombotic microangiopathy renal histology.

TAFRO (thrombocytopenia, anasarca, fever, reticulin myelofibrosis or renal dysfunction and organomegaly) syndrome is a systemic inflammatory disease characterised by thrombocytopenia, anasarca, fever or inflammatory syndrome, reticulin myelofibrosis or renal dysfunction and organomegaly. It was first described as a subtype of idiopathic multicentric Castleman disease. Here, we report the case of a 42-year-old woman presenting with thrombocytopenia, anasarca, inflammatory syndrome, renal insufficiency, reticulin myelofibrosis at bone marrow biopsy and cervical and axillary lymph nodes. Kidney biopsy showed double contours of the glomerular basement membrane, mesangiolysis and endothelial swelling compatible with thrombotic microangiopathy (TMA) as well as with TAFRO syndrome. She was successfully treated by corticosteroids, tocilizumab and rituximab. This new case description of TAFRO syndrome underlines three features of this disease rarely described in the literature and never simultaneously in the same patient: the association to severe hypothyroidism, the presence of TMA-like lesions on kidney biopsy and the treatment by the association of steroids, tocilizumab and rituximab.

Castelman's disease of the neck: a case report and literature review.

Castleman's disease is a rare pathology, poorly understood. It is considered as a lymphoproliferative disorder, described for the first time in 1954, which may be confused with other causes of lymphadenopathy. We report in this paper the case of a young women presenting with left latero-cervical lymphadenopathy. All the investigations were negative except a large high-vascularized level II cervical lymphadenopathy. We performed a cervicotomy. The extemporaneous histological exam was non-contributive. We decided to perform a complete level II and III left cervical lymphadenectomy. The diagnosis of unicentric Castleman's disease was confirmed based on the final histological study of the specimen, and the absence of other cervical and extra-cervical lymphadenopathy. The patient is free of recurrence at the time of reporting this article.

Comparison of the clinical characteristics of TAFRO syndrome and idiopathic multicentric Castleman disease in general internal medicine: a 6-year retrospective study.

BACKGROUND: Although thrombocytopenia, anasarca, fever, reticulin fibrosis and organomegaly (TAFRO) syndrome was first described as a variant of idiopathic multicentric Castleman disease (CD), patients with TAFRO syndrome demonstrate more aggressive clinical features. Because these patients may present with fever of unknown origin, general physicians need to recognise its characteristic laboratory data and clinical features during hospitalisation. AIMS: to describe the features, symptoms and characteristics of TAFRO syndrome and to compare them to those of idiopathic CD. METHODS: This was a retrospective study of patients with histopathologically confirmed TAFRO syndrome and idiopathic multicentric CD who were diagnosed and managed between April 2012 and June 2018 in a Japanese university hospital's General Medicine Department. RESULTS: We found that the hospitalisations were significantly longer among patients with TAFRO syndrome compared to those with idiopathic CD (median: 87 days; range: 34-236 days vs median: 30 days; range: 13-59 days; P < 0.01). Patients with TAFRO syndrome were more likely to present with fever, abdominal pain and elevated inflammatory markers and be misdiagnosed with an infectious disease during the first hospital visit. Approximately 40% of patients with TAFRO syndrome had no radiographically enlarged lymph nodes. CONCLUSIONS: TAFRO syndrome may present as an infectious disease with an aggressive clinical course. Our study highlights the importance of giving significance to chief complaints and laboratory data. Physicians need to recognise the clinical and laboratory features of this disease to avoid missing this potentially fatal disorder.

TAFRO Syndrome Presenting with Retroperitoneal Panniculitis-like Computed Tomography Findings at Disease Onset.

TAFRO syndrome is rare, and its pathophysiology remains unclear. We herein report the case of a 66-year-old man who presented at our emergency department with epigastric pain. Contrast-enhanced computed tomography (CT) showed high-density retroperitoneal panniculus with contrast enhancement. He was treated initially with a protease inhibitor and hydration, to little effect. Anasarca, thrombocytopenia, and renal dysfunction developed gradually, and TAFRO syndrome was diagnosed. He was treated successfully with prednisolone and cyclophosphamide, and subsequent CT findings showed improvement. Abnormal CT findings of the retroperitoneum may indicate the early stages of TAFRO syndrome before the presentation of typical ascites.

Molecular Biology of KSHV in Relation to HIV/AIDS-Associated Oncogenesis.

Discovered in 1994, Kaposi's sarcoma-associated herpesvirus (KSHV) has been associated with four human malignancies including Kaposi's sarcoma, primary effusion lymphoma, a subset of multicentric Castleman's disease, and KSHV inflammatory cytokine syndrome. These malignancies mostly occur in immunocompromised patients including patients with acquired immunodeficiency syndrome and often cause significant mortality because of the lack of effective therapies. Significant progresses have been made to understand the molecular basis of KSHV infection and KSHV-induced oncogenesis in the last two decades. This chapter provides an update on the recent advancements focusing on the molecular events of KSHV primary infection, the mechanisms regulating KSHV life cycle, innate and adaptive immunity, mechanism of KSHV-induced tumorigenesis and inflammation, and metabolic reprogramming in KSHV infection and KSHV-transformed cells.

Castleman disease mimicking systemic lupus erythematosus: A case report.

RATIONALE: Castleman disease (CD) is a nonclonal lymphoproliferative disorder sometimes manifested systemic inflammatory symptoms. Systemic lupus erythematosus (SLE) is an autoimmune disease characterized with multi-system involvement as well as broad spectrum of serum autoantibodies. When these two conditions happened to have similar clinical spectrum features, the confusion with each other occurred. PATIENT CONCERNS: A 46-year-old man suffered from chronic fever, nephrotic syndrome, acute kidney injury, anemia, thrombocytopenia and serositis, as well as hypocomplementemia and negative anti-nuclear antibody. DIAGNOSES: Meeting the classification criteria for SLE, the patient was diagnosed as SLE at first. The renal biopsy showed that he had endocapillary proliferative glomerulonephritis with negative immunofluorescence. Finally, he was diagnosed with CD after lymph nodes biopsy. INTERVENTIONS: The patient was treated with oral prednisone (50 mg daily) but got poor response. After being proved to have CD, he was treated with CHOP chemotherapy. OUTCOMES: His condition was controlled by CHOP chemotherapy. After six course of chemotherapy, the proteinuria disappeared. LESSONS: If patients, even qualified by classification criteria of SLE, had negative autoantibody or unsatisfied response to the standard treatment, the original diagnosis should be suspected. The biopsy may be help to identify the final criminals, such as CD.

Signal Transduction Pathways Associated with KSHV-Related Tumors.

Signal transduction pathways play a key role in the regulation of cell growth, cell differentiation, cell survival, apoptosis, and immune responses. Bacterial and viral pathogens utilize the cell signal pathways by encoding their own proteins or noncoding RNAs to serve their survival and replication in infected cells. Kaposi's sarcoma-associated herpesvirus (KSHV), also known as human herpesvirus 8 (HHV-8), is classified as a rhadinovirus in the γ-herpesvirus subfamily and was the eighth human herpesvirus to be discovered from Kaposi's sarcoma specimens. KSHV is closely associated with an endothelial cell malignancy, Kaposi's sarcoma, and B-cell malignancies, primary effusion lymphoma, and multicentric Castleman's disease. Recent studies have revealed that KSHV manipulates the cellular signaling pathways to achieve persistent infection, viral replication, cell proliferation, anti-apoptosis, and evasion of immune surveillance in infected cells. This chapter summarizes recent developments in our understanding of the molecular mechanisms used by KSHV to interact with the cell signaling machinery.

High proportion of TAFRO syndrome in Thai adult Castleman's disease patients: a 10-year experience.

Castleman's disease (CD) is a rare lymphoproliferative disorder, and its prevalence in Thailand is not known. This 10-year period study investigated the prevalence of CD in Thailand, and the clinical characteristics and outcomes of Thai CD patients, with special focus on the existence and prevalence of TAFRO syndrome. TAFRO syndrome is defined as CD with thrombocytopenia, anasarca, fever, reticulin fibrosis, and organomegaly. Thirty-three CD patients diagnosed and treated at Siriraj Hospital during January 2007 to December 2016 were included. The prevalence of CD was 1.4 per 1,000,000 patients/10 years. Median age was 46 years, with slight female predominance. Six patients were assigned to the TAFRO group. A high proportion of TAFRO syndrome (18.2%) was found among Thai adult CD patients. In addition to routine TAFRO diagnostic criteria, significantly lower hemoglobin and albumin levels were observed in the TAFRO group than in the non-TAFRO group. Treatment outcomes of CD patients were complete remission (52%), stable disease (30%), and death (13%). Three-year overall survival in the non-TAFRO group and TAFRO group was 88 and 50%, respectively. While most CD patients had a good prognosis, severe cases with TAFRO syndrome had poor outcome.

Castleman Disease Pathogenesis.

Castleman disease (CD) describes a group of heterogeneous disorders with common lymph node histopathologic features, including atrophic or hyperplastic germinal centers, prominent follicular dendritic cells, hypervascularization, polyclonal lymphoproliferation, and/or polytypic plasmacytosis. The cause and pathogenesis of the four subtypes of CD (unicentric CD; human herpesvirus-8-associated multicentric CD; polyradiculoneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, and skin changes [POEMS]-associated multicentric CD; and idiopathic multicentric CD) vary considerably. This article provides a summary of our current understanding of the cause, cell types, signaling pathways, and effector cytokines implicated in the pathogenesis of each subtype.

The Peripheral Neuropathies of POEMS Syndrome and Castleman Disease.

Polyneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, skin changes (POEMS) syndrome is a rare paraneoplastic disorder. The polyneuropathy can be the presenting symptom and is typically a painful, motor-predominant polyradiculoneuropathy often mimicking chronic inflammatory demyelinating polyradiculoneuropathy. The presence of a lambda monoclonal protein, elevated vascular endothelial growth factor, systemic features, and treatment resistance are clues to the diagnosis. Castleman disease (CD) is seen in a subset of these patients, and when present the neuropathy is similar but less severe. In contrast, in those patients with purely CD, the neuropathy is often a mild, painless distal sensory neuropathy.

Clinical Features of Patients with Castleman's Disease Complicated Systemic Lupus Erythematosus.

Objective To investigate the clinical features of patients with Castleman's disease (CD) and systemic lupus erythematosus (SLE). Methods According to the diagnostic information between 1994 to 2014 extracted from the database of the Medical Record Department of Peking Union Medical College Hospital (PUMCH),patients with CD and SLE were included. A thorough literature review utilizing the key words of "Castleman's disease","systemic lupus erythematosus","SLE",and "lupus" was performed in PubMed during the same period. Cases with detailed clinical information were included while cases without detailed information were excluded from the analysis of this study. Results Nine patients worldwide were available for analysis [2 cases from PUMCH,accounted for 0.03%(2/6502) of all patients diagnosed as SLE and 1.0% (2/100) of patients diagnosed as CD during the same period] with a male-to-female ratio of2:7. The median age at diagnosis of CD was 39.0 years (range:21- 60 years). All patients were diagnosed as multicentric CD with generalized peripheral lymphadenopathy. Pathologic examination showed a balanced distribution:plasma cell variant:hyaline-vascular variant:mixed variant=3:3:3. Fever was the most common symptom (88.9%,8/9). Blood system was the most commonly involved system (88.9%,8/9) and kidneys were the most commonly involved organ (88.9%,8/9). Autoimmune thrombocytopenia (AITP) was observed in 55.6% (5/9) of patients,which was significantly higher than the general SLE patients (15.0%) (P<0.01). None of the 9 patients had evidence of central nervous system involvement. Conclusions CD complicated by SLE is a rare clinical condition. Compared to the general SLE population,this subgroup of patients may have higher rate of AITP and lower rate of central nervous system involvement.

Clinical spectrum of Castleman disease-associated neuropathy.

OBJECTIVE: To define the peripheral neuropathy phenotypes associated with Castleman disease. METHODS: We conducted a retrospective chart review for patients with biopsy-proven Castleman disease evaluated between January 2003 and December 2014. Patients with associated peripheral neuropathy were identified and divided into 2 groups: those with Castleman disease without POEMS syndrome (CD-PN) and those with Castleman disease with POEMS syndrome (CD-POEMS). We used a cohort of patients with POEMS as controls. Clinical, electrodiagnostic, and laboratory characteristics were collected and compared among patient subgroups. RESULTS: There were 7 patients with CD-PN, 20 with CD-POEMS, and 122 with POEMS. Patients with CD-PN had the mildest neuropathy characterized by predominant sensory symptoms with no pain and mild distal sensory deficits (median Neuropathy Impairment Score of 7 points). Although both patients with CD-POEMS and patients with POEMS had a severe sensory and motor neuropathy, patients with CD-POEMS were less affected (median Neuropathy Impairment Score of 33 and 66 points, respectively). The degree of severity was also reflected on electrodiagnostic testing in which patients with CD-PN demonstrated a mild degree of axonal loss, followed by patients with CD-POEMS and then those with POEMS. Demyelinating features, defined by European Federation of Neurologic Societies/Peripheral Nerve Society criteria, were present in 43% of the CD-PN, 78% of the CD-POEMS, and 86% of the POEMS group. CONCLUSION: There is a spectrum of demyelinating peripheral neuropathies associated with Castleman disease. CD-PN is sensory predominant and is the mildest phenotype, whereas CD-POEMS is a more severe sensory and motor neuropathy. Compared to the POEMS cohort, those with CD-POEMS neuropathy have a similar but less severe phenotype. Whether these patients respond differently to treatment deserves further study.

Idiopathic multicentric Castleman's disease: a systematic literature review.

BACKGROUND: Multicentric Castleman's disease describes a group of poorly understood lymphoproliferative disorders driven by proinflammatory hypercytokinaemia. Patients have heterogeneous clinical features, characteristic lymph node histopathology, and often deadly multiple organ dysfunction. Human herpesvirus 8 (HHV8) causes multicentric Castleman's disease in immunosuppressed patients. The cause of HHV8-negative multicentric Castleman's disease is idiopathic; such cases are called idiopathic multicentric Castleman's disease. An absence of centralised information about idiopathic multicentric Castleman's disease represents a major challenge for clinicians and researchers. We aimed to characterise clinical features of, treatments for, and outcomes of idiopathic multicentric Castleman's disease. METHODS: We did a systematic literature review and searched PubMed, the Cochrane database, and ClinicalTrials.gov from January, 1995, with keywords including "Castleman's disease" and "giant lymph node hyperplasia". Inclusion criteria were pathology-confirmed Castleman's disease in multiple nodes and minimum clinical and treatment information on individual patients. Patients with HHV8 or HIV infection or diseases known to cause Castleman-like histopathology were excluded. FINDINGS: Our search identified 626 (33%) patients with HHV8-negative multicentric Castleman's disease from 1923 cases of multicentric Castleman's disease. 128 patients with idiopathic multicentric Castleman's disease met all inclusion criteria for the systematic review. Furthermore, aggregated data for 127 patients with idiopathic multicentric Castleman's disease were presented from clinical trials, which were excluded from primary analyses because patient-level data were not available. Clinical features of idiopathic multicentric Castleman's disease included multicentric lymphadenopathy (128/128), anaemia (79/91), elevated C-reactive protein (65/79), hypergammaglobulinaemia (63/82), hypoalbuminaemia (57/63), elevated interleukin 6 (57/63), hepatomegaly or splenomegaly (52/67), fever (33/64), oedema, ascites, anasarca, or a combination (29/37), elevated soluble interleukin 2 receptor (20/21), and elevated VEGF (16/20). First-line treatments for idiopathic multicentric Castleman's disease included corticosteroids (47/128 [37%]), cytotoxic chemotherapy (47/128 [37%]), and anti-interleukin 6 therapy (11/128 [9%]). 49 (42%) of 116 patients failed first-line therapy, 2-year survival was 88% (95% CI 81-95; 114 total patients, 12 events, 36 censored), and 27 (22%) of 121 patients died by the end of their observed follow-up (median 29 months [IQR 12-50]). 24 (19%) of 128 patients with idiopathic multicentric Castleman's disease had a diagnosis of a separate malignant disease, significantly higher than the frequency expected in age-matched controls (6%). INTERPRETATION: Our systematic review provides comprehensive information about clinical features, treatment, and outcomes of idiopathic multicentric Castleman's disease, which accounts for at least 33% of all cases of multicentric Castleman's disease. Our findings will assist with prompt recognition, diagnostic criteria development, and effective management of the disease. FUNDING: None.

Clinical spectrum and survival analysis of 145 cases of HIV-negative Castleman's disease: renal function is an important prognostic factor.

Castleman's disease (CD) is a rare lymphoproliferative disorder with clinical features and prognostic factors that are incompletely characterized. This retrospective single-center study reviewed the largest HIV-negative CD patient cohort (n = 145) to date. By clinical classification, we identified 69 patients (47.6%) as unicentric CD (UCD) and 76 patients (52.4%) as multicentric CD (MCD). Pathological classification identified 74 patients (51.0%) with the hyaline-vascular variant, 51 patients (35.2%) with the plasma-cell variant, and 20 patients (13.8%) with a mixed variant. After a median follow-up duration of 58 months (range, 1-180 months), the 1-year and 5-year survival rates were 95.1% and 91.0%, respectively. UCD patients exhibited significantly better survival (1-year and 5-year survival rates of 98.5% and 97.1%, respectively) compared with MCD patients (1-year and 5-year survival rates of 92.1% and 85.5%, respectively; p = 0.005). By univariate and multivariate Cox regression analyses, the estimated glomerular filtration rate < 60 ml/min (with the MDRD equation; hazard ratio = 4.60; 95% confidence interval, 1.50-14.12; p = 0.008) was clinically significant and represented an independent predictor for death in MCD patients. In summary, this large-scale study suggests that UCD patients enjoy better survival than MCD patients and that renal function is an important prognostic factor for MCD patients.

Diagnóstico y tratamiento actual de la enfermedad de Castleman / Current diagnosis and treatment of Castleman's disease

La enfermedad de Castleman no es una única enfermedad. Bajo este epónimo se reúne un heterogéneo grupo de trastornos linfoproliferativos no clonales, muy infrecuentes, con un amplio espectro de expresión clínica. Se han descrito 3 tipos histológicos, junto con varias formas clínicas, según la forma de presentación, el sustrato histológico y las enfermedades asociadas. La interleucina 6, los polimorfismos del receptor de esta interleucina, el virus de la inmunodeficiencia humana y el virus herpes humano tipo 8 están implicados en la etiopatogenia y su estudio ha aportado luz al conocimiento de un síndrome cuya incidencia es desconocida. A pesar de avances recientes e importantes en su conocimiento y de la progresiva experiencia terapéutica con rituximab, tocilizumab y siltuximab, aún existen preguntas difíciles de contestar con los factores etiológicos, el abordaje terapéutico óptimo y el pronóstico (AU)

Castleman's disease is not just a single disease but rather an uncommon, heterogeneous group of nonclonal lymphoproliferative disorders, which have a broad spectrum of clinical expression. Three histological types have been reported, along with several clinical forms according to clinical presentation, histological substrate and associated diseases. Interleukin-6, its receptor polymorphisms, the human immunodeficiency virus and the human herpes virus 8 are involved in the etiopathogenesis of Castleman's disease. The study of this disease has shed light on a syndrome whose incidence is unknown. Despite recent significant advances in our understanding of this disease and the increasing therapeutic experience with rituximab, tocilizumab and siltuximab, there are still difficult questions concerning its aetiology, prognosis and optimal treatment (AU)