Clinical characteristics and outcomes of Castleman disease: A multicenter study of 185 Chinese patients

Abdominal CT findings characteristic of Castleman disease: multi-centre review of 76 adult cases with abdominopelvic nodal involvement

OBJECTIVE

Characterize the CT findings of abdominopelvic Castleman disease, including a new observation involving the perinodal fat.

METHODS

Multi-centre search at 5 institutions yielded 76 adults (mean age, 42.1 ± 14.3 years; 38 women/38 men) meeting inclusion criteria of histopathologically proven Castleman disease with nodal involvement at abdominopelvic CT. Retrospective review of the dominant nodal mass was assessed for size, attenuation, and presence of calcification, and for prominence and soft-tissue infiltration of the perinodal fat. Hypervascular nodal enhancement was based on both subjective and objective comparison with aortic blood pool attenuation.

RESULTS

Abdominal involvement was unicentric in 48.7% (37/76) and multicentric in 51.3% (39/76), including 31 cases with extra-abdominal involvement. Histopathologic subtypes included hyaline vascular variant (HVV), plasma cell variant (PCV), mixed HVV/PCV, and HHV-8 variant in 39, 25, 3 and 9 cases, respectively. The dominant nodal mass measured 4.4 ± 1.9 cm and 3.2 ± 1.7 cm in mean long- and short-axis, respectively, and appeared hypervascular in 58.6% (41/70 with IV contrast). Internal calcification was seen in 22.4% (17/76). Infiltration of the perinodal fat, with or without hypertrophy, was present in 56.6% (43/76), more frequent with hypervascular vs non-hypervascular nodal masses (80.5% vs 20.7%; P < .001). Among HVV cases, 76.9% were unicentric, 71.1% appeared hypervascular, and 69.2% demonstrated perinodal fat infiltration.

CONCLUSION

Hypervascular nodal masses demonstrating prominence and infiltration of perinodal fat at CT can suggest the specific diagnosis of Castleman disease, especially the HVV.

ADVANCES IN KNOWLEDGE

Abdominopelvic nodal masses that demonstrate hypervascular enhancement and prominent infiltration of the perinodal fat at CT can suggest the diagnosis of Castleman disease, but nonetheless requires tissue sampling.

Overview of Research Status in Castleman Disease

Castleman disease (CD) is characterized by the proliferation of lymphoid tissue and encompasses a range of disorders that vary in clinical presentation, histopathological features, and therapeutic approaches. This article presents a comprehensive review of the current state of CD research, emphasizing the etiology, pathogenesis, clinical manifestations, diagnostic criteria, treatment options, and prognostic factors. CD is a relatively rare condition infrequently encountered in clinical practice. Certain subtypes of CD progress rapidly and pose a significant threat to patient health. Consequently, a timely and accurate diagnosis is crucial. This article aimed to equip clinicians and researchers with an updated and detailed understanding of CD, thereby enhancing the management of this complex condition.

A prospective study of zanubrutinib, a Bruton tyrosine kinase inhibitor, in relapsed/refractory idiopathic multicentric Castleman disease

Relapsed and refractory (R/R) idiopathic multicentric Castleman disease (iMCD) is a clinical challenge with no standard treatment. In this preliminary clinical trial, we investigated the efficacy and safety profiles of a Bruton tyrosine kinase inhibitor (BTKi), zanubrutinib, in patients with R/R iMCD. The primary endpoint was the overall response rate at Week 12 according to the Castleman Disease Collaborative Network (CDCN) response criteria. The trial was terminated early due to a lack of treatment response in the first enrolled 5 patients. Although 3 patients achieved symptomatic response, none of the 5 patients had an overall response by Week 12. One patient had progressive disease and the other 4 had stable disease. The study drug was well tolerated without grade 2 or higher adverse events. Our findings suggest that BTKi therapy is not effective for iMCD, and further attempts at single-agent therapy with zanubrutinib or other BTKis for iMCD should be considered with caution and probably avoided. This trial was registered at www.clinialtrials.gov as #NCT04743687.

Update: The molecular spectrum of virus-associated high-grade B-cell non-Hodgkin lymphomas

The vast spectrum of aggressive B-cell non-Hodgkin neoplasms (B-NHL) encompasses several infrequent entities occurring in association with viral infections, posing diagnostic challenges for practitioners. In the emerging era of precision oncology, the molecular characterization of malignancies has acquired paramount significance. The pathophysiological comprehension of specific entities and the identification of targeted therapeutic options have seen rapid development. However, owing to their rarity, not all entities have undergone exhaustive molecular characterization. Considerable heterogeneity exists in the extant body of work, both in terms of employed methodologies and the scale of cases studied. Presently, therapeutic strategies are predominantly derived from observations in diffuse large B-cell lymphoma (DLBCL), the most prevalent subset of aggressive B-NHL. Ongoing investigations into the molecular profiles of these uncommon virus-associated entities are progressively facilitating a clearer distinction from DLBCL, ultimately paving the way towards individualized therapeutic approaches. This review consolidates the current molecular insights into aggressive and virus-associated B-NHL, taking into consideration the recently updated 5th edition of the WHO classification of hematolymphoid tumors (WHO-5HAEM) and the International Consensus Classification (ICC). Additionally, potential therapeutically targetable susceptibilities are highlighted, offering a comprehensive overview of the present scientific landscape in the field.

Multicentric Castleman disease of hyaline‑vascular variant with paraneoplastic pemphigus results in abnormal lung function: Report of 3 cases

Castleman disease (CD) is clinically divided into unicentric CD (UCD) and multicentric CD (MCD). Hyaline-vascular variant (HV) is the most common pathological type of UCD, while the plasma cell type (PC) is the most common type of MCD and thus, hyaline-vascular variant multicentric CD (HV-MCD) is a rare type of CD. In addition, its etiology has remained elusive. The present study retrospectively analyzed the medical records of 3 patients diagnosed as HV-MCD admitted to The First Affiliated Hospital of Guangxi Medical University (Guangxi, China) between January 2007 and September 2020. A total of 2 males and 1 female were admitted. The areas involved varied considerably. Respiratory symptoms were seen in 3 cases, along with fever, weight loss and splenomegaly. Damage to the skin and mucous membranes resulted in oral ulcers when accompanied by paraneoplastic pemphigus (PNP). Dry and wet rales were found in all patients. All 3 cases were complicated with PNP and had hypoxemia and obstructive ventilation dysfunction. In accordance with PC-MCD, it manifested as lymph node enlargement and may involve several lymph nodes. Computed tomography mainly indicated bronchiectasis and mediastinal lymph node enlargement. In 1 case, chemotherapy failed after local mass excision, 1 case remitted after chemotherapy but the lung lesion was irreversible and 1 case was untreated and soon died of respiratory failure. The cases of HV-MCD with pulmonary involvement were induced by small airway lesions and associated with poor prognosis. Respiratory symptoms along with systemic symptoms were common.

Analysis of characteristics of four patients with adrenal unicentric Castleman disease

Background

Castleman Disease (CD) is a group of diseases with characteristic lymph node histopathology, characterized by marked enlargement of deep or superficial lymph nodes. Adrenal CD is rarely reported, and an accurate preoperative diagnosis of adrenal CD is difficult.

Method

We report four cases of CD in the adrenal gland confirmed by pathology and review the characteristics of this rare disease, highlighting the necessity of diagnostic evaluation and follow-up of the patients.

Results

All of the patients sought medical advice because of adrenal incidentalomas. No significant abnormalities were presented in the biochemistry or endocrine systems. The imaging suggested a moderate-to-large mass with uneven moderate contrast enhancement of the adrenal region, similar to a pheochromocytoma. All cases were misdiagnosed as pheochromocytomas before operation and finally confirmed by histopathology. Three cases were pathologically diagnosed as hyaline vascular CD, and one case was diagnosed as plasma cell CD. All the patients are alive without recurrence after a median follow-up of 8 years.

Conclusion

The adrenal CD should be considered after excluding pheochromocytoma and malignancy in the adrenal region. The long-term prognosis of patients with complete resection of the mass is excellent.

A national, multicenter, retrospective study of Castleman disease in China implementing CDCN criteria

Background

Castleman disease (CD) is a group of rare and heterogenous lymphoproliferative disorders including unicentric CD (UCD), human herpesvirus-8(HHV-8)-associated multicentric CD (HHV8-MCD), and HHV-8-negative/idiopathic multicentric CD (iMCD). Knowledge of CD mainly comes from case series or retrospective studies, but the inclusion criteria of these studies vary because the Castleman Disease Collaborative Network (CDCN) diagnostic criteria for iMCD and UCD were not available until 2017 and 2020, respectively. Further, these criteria and guidelines have not been systematically evaluated.

Methods

In this national, multicenter, retrospective study implementing CDCN criteria, we enrolled 1634 CD patients (UCD, n = 903; MCD, n = 731) from 2000 to 2021 at 40 Chinese institutions to depict clinical features, treatment options, and prognostic factors of CD.

Findings

Among UCD, there were 162 (17.9%) patients with an MCD-like inflammatory state. Among MCD, there were 12 HHV8-MCD patients and 719 HHV-8-negative MCD patients, which included 139 asymptomatic MCD (aMCD) and 580 iMCD meeting clinical criteria. Of 580 iMCD patients, 41 (7.1%) met iMCD-TAFRO criteria, the others were iMCD-NOS. iMCD-NOS were further divided into iMCD-IPL (n = 97) and iMCD-NOS without IPL (n = 442). Among iMCD patients with first-line treatment data, a trend from pulse combination chemotherapy toward continuous treatment was observed. Survival analysis revealed significant differences between subtypes and severe iMCD (HR = 3.747; 95% CI: 2.112-6.649, p < 0.001) had worse outcome.

Interpretation

This study depicts a broad picture of CD, treatment options and survival information in China and validates the association between the CDCN's definition of severe iMCD and worse outcomes, requiring more intensive treatment.

Fundings

Beijing Municipal Commission of Science and Technology, CAMS Innovation Fund and National High Level Hospital Clinical Research Funding.

An unexpected case of Castleman disease in porta hepatis lymphadenopathy

Castleman disease (CD) is a rare lymphoproliferative disorder that can be life threatening if left unmanaged in severe cases of inflammatory response. CD should be excluded by thorough workup in cases of lymphadenopathy and splenomegaly of unknown cause. Excisional biopsy of lymph nodes may be required to make a definitive diagnosis. A case of CD manifesting as portal hepatis lymphadenopathy is presented.

[Diagnosis and surgical treatment of a patient with Castleman disease]

Castleman disease (CD) is a benign lymphoproliferative disease. Small prevalence and diverse clinical course of disease makes it difficult to standardize diagnostics and treatment. Currently, the number of CD patients has increased with improvement in the quality of examination. Therefore, differential diagnosis of this disease is important. We present a young patient with CD and retroperitoneal non-organ neoplasm. Despite a thorough preoperative examination, the final diagnosis was established only after histological examination of surgical specimen. We discuss the diagnosis and surgical treatment of a patient with unicentric type of CD.

Analysis of albumin as a prognostic factor in HHV-8/HIV-negative Castleman disease from a multicenter study

As a rare lymphoproliferative disorder, many patients with HHV-8/HIV-negative Castleman disease (CD) have hypoalbuminemia. However, data is limited on whether hypoalbuminemia is an independent predictor of CD. We retrospectively collected data from 230 patients diagnosed at 12 medical centers in China and the U.S. Different classifications included 147 patients with unicentric CD (UCD) and 83 with idiopathic multicentric CD (iMCD). Adjusted smooth curve fitting showed that the relationship between albumin and all-cause death of patients with CD and iMCD was linear. Cox proportional hazards regression modeling showed a negative association between the risk of death and albumin level (hazard ratio [HR]: 0.84; 95% CI, 0.76, 0.93). Using the Kaplan-Meier method, we determined that hypoproteinemia was a risk factor for poorer prognosis in patients with CD, UCD, and iMCD. Albumin was independently and negatively associated with the risk of death in CD patients, especially those with iMCD.

Clinical characteristics and outcomes of Castleman disease: a multicenter Consortium study of 428 patients with 15-year follow-up

Castleman disease (CD) has been reported as a group of poorly understood lymphoproliferative disorders, including unicentric CD (UCD) and idiopathic multicentric CD (iMCD) which are human immunodeficiency virus (HIV) negative and human herpes virus 8 (HHV-8) negative. The clinical and independent prognostic factors of CD remain poorly elucidated. We retrospectively collected the clinical information of 428 patients with HIV and HHV-8 negative CD from 12 large medical centers with 15-year follow-up. We analyzed the clinicopathologic features of 428 patients (248 with UCD and 180 with iMCD) with a median age of 41 years. The histology subtypes were hyaline-vascular (HV) histopathology for 215 patients (56.58%) and plasmacytic (PC) histopathology for 165 patients (43.42%). Most patients with UCD underwent surgical excision, whereas the treatment strategies of patients with iMCD were heterogeneous. The outcome for patients with UCD was better than that for patients with iMCD, 5-year overall survival (OS) rates were 95% and 74%, respectively. In further analysis, a multivariate analysis using a Cox regression model revealed that PC subtype, hepatomegaly and/or splenomegaly, hemoglobin ≤ 80 g/L, and albumin ≤ 30 g/L were independent prognostic factors of CD for OS. The model of iMCD revealed that age > 60 years, hepatomegaly and/or splenomegaly, and hemoglobin ≤ 80 g/L were independent risk factors. In UCD, single-factor analysis identified two significant risk factors: hemoglobin ≤ 100 g/L and albumin ≤ 30 g/L. Our study emphasizes the distinction of clinical characteristics between UCD and iMCD. The importance of poor risk factors of different clinical classifications may direct more precise and appropriate treatment strategies.

Long-term treatment outcome of Castleman’s disease: A real-world experience

Background

Castleman disease (CD), classified as unicentric CD (UCD) or multicentric CD (MCD), is a rare non-neoplastic lymphoproliferative disorder of unknown origin. Owing to its rarity, the clinical characteristics, therapeutic modalities, treatment outcomes, and prognostic factors related to UCD or MCD are not well defined.

Method

We retrospectively analyzed 88 patients with CD, including those with hyaline-vascular, plasma-cell, mixed type, hypervascular, and plasmablastic subtypes, for presenting symptoms, physical, laboratory, and radiologic findings, and treatment response in the Korean population.

Results

The median patient age was 44 years (range: 18–84 years) with slight predominance of women (53.4%). UCD and MCD accounted for 38.6% (n=34) and 61.4% (n=54) of cases, respectively. Histopathologically, UCD patients were classified as 88.2% (n=30) hyaline-vascular and 11.8% (n=4) plasma cell types, whereas MCD patients were classified as 27.8% (n=15) hypervascular, 61.1% (n=33) plasma cell, 7.4% (n=4) mixed, and 3.7% (n=2) plasmablastic types. Twelve (13.6%) patients exhibited a poor performance status with an Eastern Cooperative Oncology Group score of 2. The most common presenting symptom was sustained fever, followed by fatigue, anorexia, peripheral edema, and weight loss. Furthermore, splenomegaly, pleural effusion, and ascites were observed to be associated with CD. Surgical resection and siltuximab were the preferred treatment modalities for UCD and MCD, respectively, with favorable symptomatic, laboratory, and radiologic outcomes and safety profiles. The overall survival was 90.2%, with no significant difference between the UCD and MCD groups (p=0.073), but progression-free survival was significantly poorer in the MCD group (p=0.001). Age ≥60 years and splenomegaly significantly affected the overall and progression-free survival rates.

Conclusion

Patients with UCD had favorable outcomes with surgical resection of a solitary mass, whereas in patients with MCD, old age and splenomegaly were identified as independent prognostic factors. Further well-designed prospective studies under advancing knowledge of the pathophysiology of MCD are warranted to establish suitable guidelines for the discontinuation or prolonging infusion intervals of siltuximab and treatment modalities for HHV-8 positive MCD patients or patients with siltuximab failure.

[Reactive lymphadenopathies]

The human body comprises around 600 lymph nodes as constituents of a decentralized and dispersed immune system. The main task of lymph nodes is cleaning the lymph fluid and defending the organism against outer and inner threats by bacteria, viruses and tumour cells. The histologic picture of lymph nodes reflects the different strategies of the innate and adaptive immune system, which allocates antigen presenting cells, macrophages, B‑ and T‑cell systems and reticulum cells. However, the histological picture, without any additional investigations, usually only allows speculation about the causative agent like toxoplasmosis, other bacteria or viruses. This chapter describes different lymph node reactions in detail in order to obtain a better understanding of specific immune reactions allowing a precise diagnosis and a reliable distinction from malignant processes. The last issue in particular is one of the main tasks of haematopathology. In addition to these known principles, we try to integrate results obtained with the new method of three-dimensional (3D) microscopy of fixed lymphoid tissue. At first glance, this seems to be unusual. Nevertheless, we try to apply this approach, since 3D visualization of morphological details provides distinct cellular details as well as new interpretations of cell-cell interactions and the functions of lymphoid compartments, like germinal centres and T‑zones.

[The clinical features of Castleman disease in the head and neck]

Objective:To investigate the clinicopathological features, treatment and prognosis of Castleman disease in the head and neck. Methods:The clinical and pathological data of 18 patients with Castleman disease of the head and neck in Nanjing Drum Tower Hospital from 2007 to 2021 were retrospectively analyzed. There were 14 cases of unicentric type and 4 cases of multicentric type. The clinical characteristics, treatment and prognosis were analyzed. Results:Among the 18 cases of Castleman disease in the head and neck, 1 case was located in the parotid gland, 1 case was behind the ear, 1 case was in the parapharyngeal space, 3 cases were in the neck region Ⅰ, 2 cases were supraclavicular, 2 cases were in the neck region Ⅲ, the rest were located in more than two subregions of the neck. In patients with unicentric type, no tumor recurrence and progression were found in the postoperative re-examination with neck Doppler ultrasound and CT; in the multicentric type, multiple organ dysfunction, such as edema of both lower extremities, hepatosplenomegaly, and cough, were found. Of the 4 patients with multicentric type, only 1 patient received chemotherapy, and the remaining 3 patients refused chemotherapy and only received symptomatic treatment. All patients survived during follow-up, but the disease of multicentric patients progressed significantly, and the number of involved lymph nodes increased, and hepatosplenomegaly were found in some patients. Conclusion:Castleman disease of the head and neck is mostly unicentric type, which is manifested as multiple asymptomatic enlarged lymph nodes in the neck. The surgical resection is effective and the prognosis is good. Multicentric Castleman disease of the head and neck has complex clinical symptoms and involves multiple organs over time, requiring follow-up treatment.

Castleman disease of the pancreas mimicking pancreatic malignancy on 68Ga-DOTATATE and 18F-fluorodeoxyglucose positron emission tomography/computed tomography: A case report

BACKGROUND

Castleman disease is an uncommon nonclonal lymphoproliferative disorder, which frequently mimics both benign and malignant abnormalities in several regions. Depending on the number of lymph nodes or regions involved, Castleman disease (CD) varies in diagnosis, treatment and prognosis. It rarely occurs in the pancreas alone without any distinct clinical feature and tends to be confused with pancreatic paraganglioma (PGL), neuroendocrine tumors (NETs), and primary tumors, thus impeding proper diagnosis and treatment.

CASE SUMMARY

A 28-year-old woman presented with a lesion on the neck of the pancreas, detected by ultrasound during a health examination. Physical examination and laboratory findings were normal. The mass showed hypervascularity on enhanced computed tomography (CT), significantly increased ¹⁸F-fluorodeoxyglucose uptake on positron emission tomography (PET)/CT, and slightly increased somatostatin receptor (SSTR) expression on ⁶⁸Ga-DOTATATE PET/CT, suggesting no distant metastases and subdiagnoses such as pancreatic PGL, NET, or primary tumor. Intraoperative pathology suggested lymphatic hyperplasia, and only simple tumor resection was performed. The patient was diagnosed with the hyaline vascular variant of CD, which was confirmed by postoperative immunohistochemistry. The patient was discharged successfully, and no recurrence was observed on regular review.

CONCLUSION

High glucose uptake and slightly elevated SSTR expression are potentially new diagnostic features of CD of the pancreas.

Comprehensive analysis of 65 patients with Castleman disease in a single center in China

This study aimed to investigate the epidemiologic, clinical, pathological characteristics, and treatment of patients with Castleman disease (CD) in a single center in China. We retrospectively analyzed the data of 65 Chinese CD patients, divided into unicentric CD (UCD) and multicentric CD (MCD) groups, and also microscopic subtypes as hypervascular (HV), plasmacytic (PC) and Mixed. Based on whether HHV-8 infection existed, MCD was subdivided into HHV-8-associated MCD and idiopathic Castleman disease (iMCD). Detailed epidemiologic, clinicopathological, and treatment data were analyzed and discussed. Of total 65 patients (UCD 33, MCD 32), HV (81.8%) accounted for the most of UCD and total. More females in UCD (60.6%) and more males in MCD (65.6%) were observed. CD occurred in all age groups, most commonly in 40-49 years. The mean age of onset of total was 38.5 years with PC higher than HV (45.5 vs. 35.1 years, P = 0.0413). The median diagnosis delay of MCD was longer than that of UCD (3.00 vs. 1.25 months, P = 0.0436). Abdomen (39.4%) and neck (30.3%) were the most-seen locations of lymphadenopathy in UCD, with neck (65.6%) being predominant in MCD. Mean major diameter of specimens of UCD was greater than MCD (6.4 vs. 3.1 cm, P < 0.0001). These results provided the featured and detailed profile of Castleman disease in Henan province in China with a considerable number of cases, which presented distinct evidence with other studies.

The disease course of Castleman disease patients with fatal outcomes in the ACCELERATE registry

Castleman disease (CD) describes a group of rare, potentially fatal lymphoproliferative disorders. To determine factors associated with mortality in CD, we analysed data from deceased patients in the ACCELERATE registry and compared them with matched controls. We analysed demographic, treatment and laboratory data from all deceased CD patients, matched controls and a subgroup of idiopathic multicentric Castleman disease (iMCD) patients. Of the 140 patients in ACCELERATE with a confirmed CD diagnosis, 10 had died. There were 72 patients with confirmed iMCD; six were deceased. The deceased CD cohort had more hospitalisations per year, higher overall hospitalisations and more days hospitalised per month, and received more treatment regimens per year than the matched‐control group. Analysis of laboratory values showed a significantly decreased absolute lymphocyte count at months 3 and 6 in the deceased cohort compared with controls. Among iMCD patients, there was a higher proportion of iMCD‐TAFRO (thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction and organomegaly) cases in the deceased group. The deceased iMCD group had significantly lower immunoglobulin M, international normalised ratio and platelet count. These data demonstrate that there may be differences between patients who have fatal and non‐fatal outcomes, and provide preliminary suggestions for parameters to evaluate further.

Treatment and Outcome of Castleman Disease: A Retrospective Report of 31 Patients

Background

Castleman disease (CD) is a rare and heterogeneous lymphoproliferative disorder with a spectrum of characteristic pathological abnormalities of lymph node. Furthermore, its clinical diagnosis is very challenging until pathological results are available. This study aimed to investigate the clinical presentations, treatment and prognosis of CD, thereby improving the understanding and diagnosis of CD.

Methods

This study retrospectively analyzed the clinical data of 31 patients with CD admitted to the First Hospital Affiliated Hospital of Chongqing Medical University January 2013 to December 2020. The chi-square test and the Mann–Whitney rank sum test were employed to calculate between-group differences for categorical and quantitative data, respectively.

Results

Clinically, patients with unicentric CD (UCD) usually present with lymphadenopathy. However, the clinical presentation of patients with multicentric CD (MCD) ranged from mild lymphadenopathy with B-symptoms (5/8, 62.5%) to intense inflammation, vascular leak syndrome (3/8, 37.5%), hepatosplenomegaly (3/8, 37.5%), organ insufficiency (3/8, 37.5%), and even death (2/8, 25.0%). Compared with UCD patients, patients with MCD had significantly lower levels of hemoglobin (104 (90,129) vs 137 (120,149), p=0.018) and plasma albumin (31.5 (27.0,37.0) vs 45.0 (40.0,46.5), p=0.001), but IgG levels were significantly increased. Patients with UCD were mainly treated with surgical resection alone, with a five-year survival rate of 95.65%. When siltuximab is not an option, steroid plus rituximab-based chemotherapy and specific supportive care are common options for MCD. Except for 2 deaths, the remaining MCD patients have stable disease or partial remission.

Conclusion

CD describes a heterogeneous group of disorders characterized by morphologically benign lymphoid hyperplasia. Notably, patients with MCD present varying degrees of inflammation responses, even involving multiple systems. Surgery is a direct and effective way to diagnose and treat UCD. In the absence of IL-6 antagonists, anti-inflammatory and immunosuppressive therapeutic strategies, and cytotoxic clearance of cells responsible for hypercytokinemia could be adopted.

Clinical characteristics and prognosis of patients with Castleman disease in a Chinese hospital: paraneoplastic pemphigus is an independent risk factor

OBJECTIVE

Castleman disease (CD) is a rare lymphoproliferative disorder with limited clinical research data. This study aimed to investigate the clinical manifestations, pathologic features, and prognostic factors of CD.

METHODS

The clinicopathological data of 54 patients with CD hospitalized in the First Affiliated Hospital of Nanjing Medical University were retrospectively analyzed. Univariate analysis and multivariate analysis were performed by Cox regression model to determine independent prognostic factors for patients' survival.

RESULTS

According to clinical classification, 30 cases (55.6%) had unicentric CD (UCD) and 24 cases (44.4%) had multicentric CD (MCD). Moreover, pathologic classification revealed 32 cases (59.3%) with hyaline vascular variant, 3 (5.6%) with mixed cellular variant, and 19 (35.2%) with plasmacytic variant. Patients with MCD commonly presented with clinical signs and symptoms, including fever, splenomegaly, and pleural effusion and/or ascites. Clinical complications, such as liver injury, anemia, and polyradiculoneuropathy, organomegaly, endocrinopathy, monoclonal plasma cell disorder, skin changes (POEMS) syndrome were more common in patients with MCD. Univariate analysis showed that the presence of paraneoplastic pemphigus (PNP) and the elevation of C-reactive protein were unfavorable prognosticators of survival in patients with CD. By multivariate analysis PNP was an independent prognostic factor in patients with CD.

CONCLUSIONS

This study provided a panoramic elaboration of CD cases and showed that the presence of PNP was an independent unfavorable factor.

A prospective, multicenter study of bortezomib, cyclophosphamide, and dexamethasone in relapsed/refractory iMCD

Relapsed and refractory (R/R) idiopathic Multicentric Castleman disease (iMCD) is a clinical challenge with few treatment options. In this first multicenter, prospective trial which implemented the recently published CDCN response criteria, we evaluated the efficacy and safety profiles of bortezomib-cyclophosphamide-dexamethasone (BCD) regimen in 24 R/R iMCD patients. By 6 months, 15 patients (62.5%) achieved overall treatment responses; four patients (16.7%) had stable disease and five patients (20.8%) suffered from progression of disease. Even when considering all patients, there were significant (p < .05) improvements in median symptom score, hemoglobin, platelet count, C-reactive protein (CRP) erythrocyte sedimentation rate (ESR), IL-6, albumin, and immunoglobin G (IgG) after treatment. The regimen was well tolerated without grade 3 or higher adverse events. Estimated 1-year progression-free survival (PFS) and overall survival (OS) were 79% and 92%, respectively. BCD regimen is an effective and safe treatment option for R/R iMCD patients. This trial was registered at www.chictr.org.cn as # ChiCTR1800019342.

Cutaneous Manifestations of Castleman Disease: Histopathological Characteristics and Review of Literature

ABSTRACT

Castleman disease (CD) is a poorly understood lymphoproliferative disorder characterized by enlarged lymph nodes. The spectrum of differential diagnoses is wide, and it is hard to differentiate from other diseases. Cutaneous involvement of CD is rare, and studies that describe cutaneous dermatopathology of CD are scarce. The aim of this study was to collect case reports of CD with cutaneous manifestations and identify potential relevant histopathological features. We found that cases of CD with cutaneous manifestations often exhibited dermal lymphoid follicles with follicle center infiltration of lymphocytes and plasma cells. These dermal follicles also had regressive or atrophic germinal centers and were penetrated by hyalinized vessels. Patients with CD also consistently exhibited perivascular and deep dermal inflammatory infiltrate, primarily composed of lymphocytes and plasma cells. We intend to raise awareness of this rare entity and provide more histopathological information regarding its dermatological manifestations.

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.

UCD with MCD-like inflammatory state: surgical excision is highly effective

Unicentric Castleman disease (UCD) is a rare lymphoproliferative disorder presenting as a single nodal mass with characteristic histopathology. Patients with UCD are typically asymptomatic with normal laboratory markers, whereas patients with multicentric Castleman disease (MCD) demonstrate multicentric lymphadenopathy and cytokine storm-induced systemic inflammatory symptoms. This retrospective analysis of 116 UCD cases identified 19 (16.4%) cases with an MCD-like inflammatory state (UCD-MIS). We compared treatments and outcomes between cases of UCD-MIS and UCD-non-MIS to evaluate the role of surgery and illuminate biological behavior of UCD-MIS. There were differences in the distribution of histopathological subtypes (plasmacytic histopathology was more frequently seen, 52.6% vs 13.4%; P < .001) between the 2 groups. However, both groups demonstrated good responses to surgical treatment, suggesting that UCD-MIS in some patients still shared common biological behavior with UCD in other patients. Sixteen (94.2%) patients with UCD-MIS underwent complete surgical excision alone, and the systemic inflammation resolved completely in all of them. This high response rate suggests surgical treatment as a potential cure for this unique subset of patients. After a median follow-up duration of 64 months (range, 2-239 months), neither lymphadenopathy nor the inflammatory state recurred. However, inflammation may progress in patients with irresectable disease, and treatment options other than surgery should be considered in these patients.

Idiopathic Multicentric Hyaline Vascular-Type Castleman Disease

Castleman disease is a rare lymphoproliferative disorder presenting with localized or disseminated lymphadenopathy and systemic symptoms. It can be categorized clinically as unicentric or multicentric, histopathologically as hyaline vascular, plasma cell, or mixed variant, and etiologically, considering the subtypes based on causative viral agents and associated syndromes. The multicentric type can mimic other haematological malignancies, ranging from asymptomatic to multiple organ involvement. Although its pathophysiology is not well known, the current approved treatments are directed towards interleukin-6, CD-20, and viral agents. The authors present an 82-year-old leucodermic man presented with a 2-week history of constitutional symptoms. Examination revealed pallor, hepatosplenomegaly, and palpable left axillary lymphadenopathy. Investigation showed anaemia, thrombocytopenia, polyclonal hypergammaglobulinemia, hypoalbuminemia, and high acute phase reactants, with image study revealing multiple axillary, mediastinal, inguinal, and pelvic lymphadenopathies. The lymph node biopsy was consistent with hyaline vascular-type Castleman disease without human herpersvirus-8 markers. He started prednisolone with initial improvement evolved poorly on a short term. Castleman disease has a broad spectrum of clinical manifestations, associations, and complications that bring a diagnostic challenge, requiring a multidisciplinary approach. Clinicians should be familiar with its features because proper diagnosis and aggressive targeted treatment are the pillars of proper management of these patients.

Emerging role of 18F-FDG PET/CT in Castleman disease: a review

Castleman disease (CD) describes a group of rare hematologic conditions involving lymphadenopathy with characteristic histopathology and a spectrum of clinical abnormalities. CD is divided into localized or unicentric CD (UCD) and multicentric CD (MCD) by imaging. MCD is further divided based on etiological driver into human herpesvirus-8-associated MCD, POEMS-associated MCD, and idiopathic MCD. There is notable heterogeneity across MCD, but increased level of pro-inflammatory cytokines, particularly interleukin-6, is an established disease driver in a portion of patients. FDG-PET/CT can help determine UCD versus MCD, evaluate for neoplastic conditions that can mimic MCD clinico-pathologically, and monitor therapy responses. CD requires more robust characterization, earlier diagnosis, and an accurate tool for both monitoring and treatment response evaluation; FDG-PET/CT is particularly suited for this. Moving forward, future prospective studies should further characterize the use of FDG-PET/CT in CD and specifically explore the utility of global disease assessment and dual time point imaging.

Trial registration ClinicalTrials.gov, NCT02817997, Registered 29 June 2016, https://clinicaltrials.gov/ct2/show/NCT02817997

An Immunocompetent HIV-Negative Elderly Patient with Low-Grade Fever, Generalized Lymphadenopathy, Splenomegaly, and Acute Phase Response: Do Not Forget Castleman Disease

Multicentric Castleman disease (MCD) is a rare lymphoproliferative disorder that mainly affects middle-aged patients with human immunodeficiency virus (HIV) infection. However, HIV-negative patients can also be affected representing a small proportion of the total MCD cases. Of note, recent studies from China in HIV-negative patients with MCD have suggested that the onset of the disease can be observed in younger age than previously thought. If undiagnosed and untreated, the MCD has a poor prognosis and may progress to lymphoma. We present an 82-year-old immunocompetent male patient who was admitted to our department because of low-grade fever, cachexia, anasarca, hepatosplenomegaly, and generalized lymphadenopathy. Laboratory findings showed anemia and increased markers of inflammation including hyperferritinemia and polyclonal hyperglobulinemia. Infectious causes including HIV were ruled out. Histological examination of a cervical lymph-node revealed lesions supportive of MCD diagnosis. Of note, the outer-zone plasmablasts' nuclei stained positive for human herpesvirus-8 (HHV8). The patient received 4 cycles of cyclophosphamide, vincristine, and dexamethasone with regression of all symptoms. This case underlines that HHV8-associated MCD should be considered as a rare cause of generalized lymphadenopathy even in HIV-negative immunocompetent patients when other causes have been appropriately excluded because a timely diagnosis can be life-saving.

Adult Langerhans cell histiocytosis of skull in a patient with synchronous papillary thyroid carcinoma and Castleman disease

We report an extremely rare case of adult Langerhans cell histiocytosis (LCH) in a patient with papillary thyroid carcinoma (PTC) and Castleman disease (CD). A 46-year-old man visited our hospital with anaemia; systemic imaging showed an abdominal and a left thyroid mass. Biopsy confirmed CD for the abdominal mass and PTC for the thyroid mass. Two months after, he presented with headache and a right parietal lump. Brain CT and enhanced MRI revealed an osteolytic mass with enhancement in the right parietal skull. Surgical removal and biopsy confirmed the diagnosis of skull LCH. The BRAF mutation was positive on PTC and negative on CD and LCH. We conducted surgical resection only for PTC and LCH; surgical resection with siltuximab for multicentric CD. At the 25-month follow-up, there was no recurrence or progression. We may consider of syndromic nature of these diseases to establish a treatment strategy.

Multicentric Plasma-Cell Type Castleman Disease Masquerading As Hodgkin Lymphoma: A Case Report

Castleman disease (CD), or angiofollicular hyperplasia, or giant lymph node hyperplasia, is a heterogeneous benign lymphoproliferative disorder of unknown etiology. It has three distinct histologic subtypes (hyaline vascular, plasma cell, and mixed hyaline vascular plasma cell types) as well as unicentric Castleman disease (UCD) and multicentric Castleman disease (MCD) variants. In the unicentric form, the disease is confined to one anatomical lymph node and usually with no systemic symptoms. However, in the multicentric form (further subdivided into idiopathic MCD, human herpes virus-8-associated MCD, and POEMS-associated MCD), lymphadenopathy is more generalized with more aggressive systemic symptoms mimicking a malignant lymphoma. Therefore, this case report aims to underscore the importance of immunohistochemical evaluation as an indispensable ancillary technique to routine histopathological examination of a lymph node biopsy specimen, as a gold standard for definitive diagnosis of proliferative lymph node lesions.

FDG PET/CT Findings of Castleman Disease Assessed by Histologic Subtypes and Compared with Laboratory Findings

Castleman disease (CD) is a relatively rare lymphoproliferative disorder and the pathophysiology of the subtypes are incompletely understood. Fluorine-18 fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT) demonstrates the metabolic activity of inflammatory and tumorous conditions. The FDG uptake intensity and sites of involved lesions on FDG PET/CT were assessed by histologic subtypes, and compared to the patient's hemoglobin, platelet, albumin, and high-sensitivity C-reactive protein (hs-CRP) levels. In total, 60 PET/CT images of 44 consecutive CD patients were included: 4 (9%) unicentric and 40 (91%) multicentric; 21 (48%) hyaline vascular subtype, 16 (36%) plasma cell, and 7 (16%) mixed or unclassified. The maximum standardized uptake value (SUVmax) and tumor-to-liver (T/L) ratio of involved lymph nodes (LNs) were 5.3 ± 2.4 (range, 1.6-11.5) and 2.8 ± 1.6 (range, 1.1-9.6), respectively, with no significant difference between the histologic subtypes. Higher number of involved LN stations and presence of extra-nodal involvement on FDG PET/CT were associated with thrombocytopenia, hypoalbuminemia, and elevated hs-CRP levels (p values < 0.05). FDG-avidity was not different by histologic subtypes and did not correlate with laboratory findings. However, the extent of nodal and extra-nodal involvement as noted on FDG PET/CT was significantly associated with abnormal laboratory findings in patients with CD.

Unicentric Castleman's Disease with an Unusual Clinical Behavior

Castleman’s disease is a rare clinicopathological condition characterized by hyperplasia of lymph nodes. We report the case of a 12-year-old boy who presented with painful oral and genital ulcers, who was assumed to have Behçet’s disease. However, the patient did not show any clinical improvement on colchicine and systemic corticosteroids. Later, the patient developed severe abdominal pain and vomiting. Abdominal CT revealed a mass lesion superior to the right kidney. After a thorough investigation, he was diagnosed with unicentric Castleman’s disease. Despite the complete resection of the mass, the patient continued to have the symptoms of abdominal pain and orogenital ulcers. Immunomodulatory therapy resulted in remarkable clinical improvement. This case report demonstrates how unicentric Castleman’s disease can share similar clinical behavior to the multicentric disease.

[Analysis of the clinicopathologic features as well as diagnosis and treatment of 59 patients with Castleman disease]

Objective: To investigate the clinicopathologic features, treatment, and prognosis in patients with Castleman disease (CD) . Methods: We retrospectively analyzed the clinicopathologic data of 59 patients for whom a diagnosis of Castleman disease was confirmed using pathological examination from October 2011 to October 2019 at the Henan Cancer Hospital. The patients were divided into the following two groups as per the following clinical classifications: unicentric CD (UCD, n=47) and multicentric CD (MCD, n=12) . Data on clinical manifestations, laboratory findings, treatment, and prognosis were analyzed. Results: There was no significant difference in the median age and the ratio of male to female between the UCD and MCD. UCD was characterized by asymptomatic enlargement of the single lymph node. The main pathological type was hyaline vascular histopathology (83.0%) . Of these, 44 patients chose surgical resection, and their prognosis was good. Treatment. MCD was characterized by multiple enlarged superficial and/or deep lymph nodes with B symptoms, weakness, and hepatosplenomegaly. Anemia, hypoproteinemia, and globulin level were increased on laboratory examinations. Plasmacyte histopathology was the main pathological type and was present in about 50.0% of the subjects. Only chemotherapy was performed for these MCD patients, followed by chemotherapy or chemotherapy followed by radiotherapy, and the efficient was 58.3% (7/12) . Conclusions: UCD, characterized by asymptomatic enlargement of the single lymph node, shows good postoperative prognosis. MCD has relatively complex clinical manifestations and poor prognosis, and optimal treatment is yet to be established.

Predominant Stroma-Rich Feature in Hyaline Vascular Variant of Castleman Disease Is Associated With Paraneoplastic Pemphigus

OBJECTIVES

We aimed to describe the clinical and histopathologic features of Castleman disease (CD), particularly emphasizing its associations with paraneoplastic pemphigus (PNP) and prognosis.

METHODS

We retrospectively enrolled 123 CD patients at our center. Clinical, pathologic, and laboratory data were reviewed.

RESULTS

Fifty percent of the patients had PNP. Compared with those without PNP, patients with PNP-associated CD had more hyaline vascular (HV) variants (83.9% vs 57.4%), fewer mixed cellular variants (16.1% vs 24.6%), and no plasmacytic variants (0% vs 18.0%). Thirty-eight of 87 patients with the HV variant of CD (HV-CD) had stroma-rich (SR) features, and the incidence rate was higher in those with PNP-associated CD than in those without PNP (48.4% vs 13.1%, P < .001). The SR variant was associated with higher PNP-associated IgG titers than SR absence before surgery (median 1:160 vs 1:80, P = .019) or after surgery (median 1:160 vs 1:40, P = .013). The SR variant was also an unfavorable prognostic factor for CD survival in univariate analysis. The 3-year survival rates were 47.5% among those with PNP and 87.7% among those without PNP (P < .001).

CONCLUSIONS

PNP is associated with specific subtypes of CD and affects survival. The SR variant of HV-CD positively correlates with the incidence of PNP.

Different Imaging Features of Retroperitoneal Unicentric Castleman's Disease: A Case Report

Castleman's disease is a rare disease which is difficult to diagnose early due to its lack of specific manifestations, and also is easily confused with lymphoma or other solid tumors. Castleman's disease can occur in any part of the body containing lymph nodes and is most common in the chest, followed by the neck, abdomen, and axillae. A 37-year-old woman was admitted to our hospital because of a tumor near the adrenal gland found by computed tomography. Positron emission tomography-computed tomography revealed that the retroperitoneal tumor may be a malignant disease. However, the pathological diagnosis after laparoscopic resection was retroperitoneal Castleman's disease, hyaline vascular type.

AA amyloidosis associated with Castleman disease: A case report and review of the literature

RATIONALE

AA amyloidosis (AA) is caused by a wide variety of inflammatory states, but is infrequently associated with Castleman disease (CD). CD describes a heterogeneous group of hematologic disorders that share characteristic lymph node histopathology. CD can present with a solitary enlarged lymph node (unicentric CD, UCD) or with multicentric lymphadenopathy (MCD), constitutional symptoms, cytopenias, and multiple organ dysfunction due to an interleukin-6 driven cytokine storm.

PATIENT CONCERNS

We are reporting a case of a 26-year-old woman with no significant past medical history who presented with a 3-month history of fatigue and an unintentional 20-pound weight loss.

DIAGNOSIS

A CT-scan of the abdomen and pelvis revealed hepatosplenomegaly and a mesenteric mass. Congo Red staining from a liver biopsy showed apple-green birefringence and serum markers were suggestive of an inflammatory process. Post-excision examination of the resected mass revealed a reactive lymph node with follicular hyperplasia with kappa and lambda stains showing polyclonal plasmacytosis consistent with CD.

INTERVENTIONS

The patient underwent surgery to remove the affected lymph node.

OUTCOMES

IL-6, anemia, leukocytosis, and thrombocytosis resolved or normalized 2 weeks after resection; creatinine normalized 9 months postsurgery. Twenty two months post-surgery her IFN-γ normalized, her fatigue resolved, her proteinuria was reduced by >90% and she had returned to her baseline weight.

LESSONS

Our case and literature review suggest that patients presenting with UCD or MCD along with organ failure should prompt consideration of concurrent AA amyloidosis.

Clinical features and treatment of 7 Chinese TAFRO syndromes from 96 de novo Castleman diseases: a 10-year retrospective study

Background

Castleman disease (CD) is a rare polyclonal lymphoproliferative disorder with unknown etiology. TAFRO syndrome is now regarded as a specific subtype of CD, and is still a huge challenge for clinicians.

Methods

To clarify the clinical features and management of TAFRO syndrome in China, we retrospectively analyzed 96 patients with HIV-negative CD (52 with unicentric CD and 44 with multicentric CD), who were diagnosed and treated at our center between 2008 and 2017. Specially, we systematically reviewed the 7 TAFRO syndrome cases based on the 2015 criteria proposed by Masaki.

Results

Among the 7 cases, there were 3 men and 4 women, and the median age was 53 years. The main symptoms included thrombocytopenia (7/7), anasarca (7/7), fever (4/7), renal dysfunction (7/7), and organomegaly (6/7). One patient was treated with corticosteroid monotherapy, one received RD (Rituximab, dexamethasone), and 5 received CHOP/COP like chemotherapy as first-line treatment, 2 of the 5 combined with Rituximab. Four patients needed hemodialysis or CRRT because of progressive renal failure. The outcome for TAFRO syndrome was significantly worse compared to other types of CD. Although 3 patients improved after early treatment, 4 patients died due to disease progression, and only one patient achieved complete resolution of all the symptoms after changing to lenalidomide based regimen.

Conclusions

This study reveals that TAFRO syndrome is more severe and has more systemic symptoms than other iMCD, most cases need active treatment, and their prognoses are poor. Lenalidomide based regimen may be as a promising new therapy for TAFRO syndrome.

A novel FAS mutation with variable expressivity in a family with unicentric and idiopathic multicentric Castleman disease

FAS can be mutated in individuals diagnosed with unicentric and idiopathic multicentric Castleman disease. Defective lymphocyte apoptosis may be a pathological mechanism shared between Castleman disease and autoimmune lymphoproliferative syndrome.

Is TAFRO syndrome a subtype of idiopathic multicentric Castleman disease?

Castleman disease (CD) is a rare lymphoproliferative disorder that can be unicentric or multicentric. Multicentric CD (MCD) is further subdivided into human herpesvirus type-8-associated, POEMS syndrome-associated, and idiopathic (iMCD). TAFRO syndrome is a newly identified disorder of unknown etiology characterized by thrombocytopenia, anasarca, fever, reticulin myelofibrosis, renal dysfunction, and organomegaly. The TAFRO syndrome is sometimes regarded as a subtype of iMCD (TAFRO-iMCD), whereas iMCD without TAFRO syndrome is considered "not otherwise specified" (iMCD-NOS). However, a proportion of patients with TAFRO syndrome have been diagnosed without lymph node biopsies (TAFRO syndrome without proven iMCD; TAFRO-w/op-iMCD). To clarify the clinical features of iMCD-NOS, TAFRO-iMCD, and TAFRO-w/op-iMCD, we retrospectively analyzed 220 patients extracted from the database of the Multicenter Collaborative Retrospective Study for Establishing the Concept of TAFRO Syndrome. The patients included 87 with iMCD-NOS, 63 with TAFRO-iMCD, and 19 with TAFRO-w/op-iMCD. Patients in all three groups exhibited anemia, hypoalbuminemia, and elevated serum C-reactive protein and interleukin-6 levels. No significant differences in clinical, laboratory, and prognostic features were noted between the TAFRO-iMCD, and TAFRO-w/op-iMCD groups. However, the iMCD-NOS group exhibited polyclonal hyper-γ-globulinemia. The five-year survival rates of patients in the iMCD-NOS and TAFRO-involved groups were 100% and 66.5%, respectively (dropping markedly during the first few months in the latter). The iMCD-NOS and the TAFRO-iMCD samples typically showed plasma cell and mixed-type histologies, respectively. Thus, iMCD can be classified into two distinct subtypes, iMCD-NOS and TAFRO-iMCD. As such, TAFRO-iMCD and TAFRO-w/op-iMCD may be considered the same entity, requiring prompt diagnosis and intensive care.

Human Herpesvirus-8 Negative Multicentric Castleman Disease in a Patient with Human Immunodeficiency Virus Treated with Highly Active Antiretroviral Therapy and Chemotherapy

Multicentric Castleman disease (MCD) is a rare lymphoproliferative disorder with a high mortality rate in undiagnosed patients. Traditionally, human immunodeficiency virus (HIV) positive MCD occurs due to infection with human herpes virus-8 (HHV), which is thought to play a role in the pathogenesis of MCD. We present the case of a 49-year-old woman who was referred to our oncology clinic for generalized lymphadenopathy in a waxing and waning pattern for the last four years. She was found to be HIV positive. Here we report a rare case of HIV-positive, HHV-negative MCD that responded to prompt treatment with highly active antiretroviral therapy (HAART) followed by chemotherapy as evidenced by improved CD4+ T cell numbers and reduction in lymphadenopathy. The findings in this HHV seronegative patient may indicate an alteration in the virulence and tropism between HHV and HIV, and further demonstrate the need for continued investigation into the pathogenesis of Castleman disease.

Phase 2 study using oral thalidomide-cyclophosphamide-prednisone for idiopathic multicentric Castleman disease

Idiopathic multicentric Castleman disease (iMCD) is a rare lymphoproliferative disorder. The anti–interleukin 6 (IL-6) therapy siltuximab is not available everywhere, and is not effective for over one-half of patients. Alternative treatment approaches are urgently needed. In the first iMCD clinical trial directed against a target other than IL-6 signaling, we investigated a thalidomide-cyclophosphamide-prednisone (TCP) regimen in newly diagnosed iMCD patients. This single-center, single-arm, phase 2 study enrolled 25 newly diagnosed iMCD patients between June 2015 and June 2018. The TCP regimen (thalidomide 100 mg daily for 2 years; oral cyclophosphamide 300 mg/m2 weekly for 1 year; prednisone 1 mg/kg twice a week for 1 year) was administered for 2 years or until treatment failure. The primary end point was durable tumor and symptomatic response for at least 24 weeks. Twelve patients (48%) achieved the primary end point with no relapse, 3 patients (12%) demonstrated stable disease, and 10 patients (40%) were evaluated as treatment failure. Even when considering all patients, there were significant (P &lt; .05) improvements in median symptom score, IL-6 level, hemoglobin, erythrocyte sedimentation rate, albumin, and immunoglobulin G. Among responders, the median levels of all evaluated parameters significantly improved, to the normal range, after treatment. The regimen was well tolerated. One patient died of pulmonary infection and 1 patient had a grade 3 adverse event (rash); 2 patients died following disease progression. Estimated 1-year progression-free survival and overall survival were 60% and 88%, respectively. The TCP regimen is an effective and safe treatment of newly diagnosed iMCD patients, particularly when siltuximab is unavailable. This trial was registered at www.clinicaltrials.gov as #NCT03043105.

The Collaborative Network Approach: a model for advancing patient-centric research for Castleman disease and other rare diseases

There are ∼7000 rare diseases affecting 30 000 000 individuals in the U.S.A. 95% of these rare diseases do not have a single Food and Drug Administration-approved therapy. Relatively, limited progress has been made to develop new or repurpose existing therapies for these disorders, in part because traditional funding models are not as effective when applied to rare diseases. Due to the suboptimal research infrastructure and treatment options for Castleman disease, the Castleman Disease Collaborative Network (CDCN), founded in 2012, spearheaded a novel strategy for advancing biomedical research, the 'Collaborative Network Approach'. At its heart, the Collaborative Network Approach leverages and integrates the entire community of stakeholders - patients, physicians and researchers - to identify and prioritize high-impact research questions. It then recruits the most qualified researchers to conduct these studies. In parallel, patients are empowered to fight back by supporting research through fundraising and providing their biospecimens and clinical data. This approach democratizes research, allowing the entire community to identify the most clinically relevant and pressing questions; any idea can be translated into a study rather than limiting research to the ideas proposed by researchers in grant applications. Preliminary results from the CDCN and other organizations that have followed its Collaborative Network Approach suggest that this model is generalizable across rare diseases.

Novel insights and therapeutic approaches in idiopathic multicentric Castleman disease

Castleman disease (CD) describes a heterogeneous group of hematologic disorders that share characteristic lymph node histopathology. Patients of all ages present with either a solitary enlarged lymph node (unicentric CD) or multicentric lymphadenopathy (MCD) with systemic inflammation, cytopenias, and life-threatening multiple organ dysfunction resulting from a cytokine storm often driven by interleukin 6 (IL-6). Uncontrolled human herpesvirus-8 (HHV-8) infection causes approximately 50% of MCD cases, whereas the etiology is unknown in the remaining HHV-8-negative/idiopathic MCD cases (iMCD). The limited understanding of etiology, cell types, and signaling pathways involved in iMCD has slowed development of treatments and contributed to historically poor patient outcomes. Here, recent progress for diagnosing iMCD, characterizing etio-pathogenesis, and advancing treatments are reviewed. Several clinicopathological analyses provided the evidence base for the first-ever diagnostic criteria and revealed distinct clinical subtypes: thrombocytopenia, anasarca, fever, reticulin fibrosis/renal dysfunction, organomegaly (iMCD-TAFRO) or iMCD-not otherwise specified (iMCD-NOS), which are both observed all over the world. In 2014, the anti-IL-6 therapy siltuximab became the first iMCD treatment approved by the US Food and Drug Administration, on the basis of a 34% durable response rate; consensus guidelines recommend it as front-line therapy. Recent cytokine and proteomic profiling has revealed normal IL-6 levels in many patients with iMCD and potential alternative driver cytokines. Candidate novel genomic alterations, dysregulated cell types, and signaling pathways have also been identified as candidate therapeutic targets. RNA sequencing for viral transcripts did not reveal novel viruses, HHV-8, or other viruses pathologically associated with iMCD. Despite progress, iMCD remains poorly understood. Further efforts to elucidate etiology, pathogenesis, and treatment approaches, particularly for siltuximab-refractory patients, are needed.

Novel insights and therapeutic approaches in idiopathic multicentric Castleman disease

Castleman disease (CD) describes a heterogeneous group of hematologic disorders that share characteristic lymph node histopathology. Patients of all ages present with either a solitary enlarged lymph node (unicentric CD) or multicentric lymphadenopathy (MCD) with systemic inflammation, cytopenias, and life-threatening multiple organ dysfunction resulting from a cytokine storm often driven by interleukin 6 (IL-6). Uncontrolled human herpesvirus-8 (HHV-8) infection causes approximately 50% of MCD cases, whereas the etiology is unknown in the remaining HHV-8-negative/idiopathic MCD cases (iMCD). The limited understanding of etiology, cell types, and signaling pathways involved in iMCD has slowed development of treatments and contributed to historically poor patient outcomes. Here, recent progress for diagnosing iMCD, characterizing etio-pathogenesis, and advancing treatments are reviewed. Several clinicopathological analyses provided the evidence base for the first-ever diagnostic criteria and revealed distinct clinical subtypes: thrombocytopenia, anasarca, fever, reticulin fibrosis/renal dysfunction, organomegaly (iMCD-TAFRO) or iMCD-not otherwise specified (iMCD-NOS), which are both observed all over the world. In 2014, the anti-IL-6 therapy siltuximab became the first iMCD treatment approved by the US Food and Drug Administration, on the basis of a 34% durable response rate; consensus guidelines recommend it as front-line therapy. Recent cytokine and proteomic profiling has revealed normal IL-6 levels in many patients with iMCD and potential alternative driver cytokines. Candidate novel genomic alterations, dysregulated cell types, and signaling pathways have also been identified as candidate therapeutic targets. RNA sequencing for viral transcripts did not reveal novel viruses, HHV-8, or other viruses pathologically associated with iMCD. Despite progress, iMCD remains poorly understood. Further efforts to elucidate etiology, pathogenesis, and treatment approaches, particularly for siltuximab-refractory patients, are needed.

Thoracic Paraspinal Castleman Disease in a Young Mexican-American Man with Postcoital Hematuria

BACKGROUND

Castleman disease (CD) is an uncommon disorder of deregulated lymphoproliferation with unicentric (UCD) and multicentric forms based on extent of nodal involvement. Gross resection with histopathologic analysis remains the gold standard for diagnosis of UCD and is curative in most cases. Symptomatic paraspinal UCD is a rare presentation with potentially dangerous complications, and its tendency to mimic more common spinal tumors presents a significant diagnostic challenge.

CASE PRESENTATION

A 25-year-old Hispanic man with no past medical history was evaluated for a known left-sided paraspinal mass that was incidentally discovered during an emergency department work-up for hematuria. Computed tomography on initial presentation revealed a 5.3 cm × 3.3 cm × 4.8 cm heterogeneously enhancing left paraspinal mass adjacent to the T11 vertebral body with tonguelike extension into the T11-T12 neural foramen. Although he remained neurologically intact throughout most of the diagnostic work-up, an inconclusive biopsy, worsening hematuria, and late-onset radiculopathy with severe back pain prompted surgical intervention. Microscopic histomorphology was consistent with CD. He continued to have intermittent hematuria and dysuria postoperatively, but repeat computed tomography at 7 months confirmed no recurrence of the mass.

CONCLUSIONS

Compared with previous reports, our case of postcoital hematuria and radiculopathy accompanying a paraspinal thoracic mass in a young Mexican-American man is a unique presentation. Awareness and early consideration of UCD in the work-up of a paraspinal mass may spare affected patients adverse and dangerous sequelae, such as spinal cord compression and excessive intraoperative hemorrhage.

Clinical characteristics and outcomes of Castleman disease: A multicenter study of 185 Chinese patients

Castleman disease (CD) is a rare lymphoproliferative disorder. To assess the clinical features, outcomes, and prognostic factors of this disease, we retrospectively analyzed 185 HIV-negative CD patients from four medical centers in southern China. The median age was 37 years. One hundred and twenty-one patients (65.4%) were classified as unicentric CD (UCD) and 64 patients (34.6%) were classified as multicentric CD (MCD). The histology subtype was hyaline-vascular for 132 patients (71.4%), plasma cell for 50 patients (27%), and mixed type for 3 patients (1.6%). The 5-year overall survival (OS) of 185 CD cases was 80.3%. All UCD patients underwent surgical excision, whereas the treatment strategies of MCD patients were heterogeneous. The outcome for UCD patients was better than MCD patients, with 5-year OS rates of 93.6% and 51.2%, respectively. In further analysis of the MCD subgroup, a multivariate analysis using a Cox regression model revealed that age, splenomegaly and pretreatment serum albumin level were independent prognostic factors for OS. This multicenter study comprising the largest sample size to date suggested that MCD is a distinct entity from UCD with a significantly worse outcome. Older age (≥40 years), splenomegaly, and hypoalbuminemia were risk factors for poorer MCD prognosis.