Intensity modulated radiation therapy (IMRT) for the treatment of unicentric Castlemans disease: a case report and review of the use of radiotherapy in the literature

Castleman's disease: A report of two cases at a tertiary hospital in Northern Tanzania

Castleman's disease is a rare lympho-proliferative disease entity characterized by variable clinical presentations, distinctive histological manifestations, and prognosis. Its incidence and etiology are unclear. An interplay of HIV and human herpesvirus-8 has been implicated. Although its localized variety is benign, other types can be multifocal with adverse systemic manifestations. Human herpesvirus-8 Castleman's disease affects mainly HIV-positive individuals; however, individuals who are immunocompromised from other causes can also be affected, thus necessitating investigations for HIV. Herein, we report two patients presenting with long-standing lymphadenopathy. Histopathology, immunohistochemical testing and clinico-pathological correlation confirmed the diagnosis of Castleman's disease. The patients were successfully treated with surgery and/or rituximab. They were symptoms free in the subsequent follow-up visits. A brief review of the literature is also provided.

Unicentric Castleman's disease of hepatic hilum and retroperitoneum: a case report for endoscopic ultrasonography differential diagnosis and a literature review

Castleman's disease (CD) is a highly heterogeneous clinico-pathological entity belonging to the lymphoproliferative disorders. CD can occur in any part of the human body where lymph nodes are present. In addition, very few cases have been reported in hepatic hilum. Here, we present a case of a middle-aged female patient who was presented with abdominal pain and diagnosed as localized Castleman's disease of hepatic hilar and retroperitoneal origin. Diagnosing CD is complex due to its resemblance to many other diseases. EUS and FNA may play a more important role in differential diagnosis of CD and other disease in digestive system.

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.

Castleman disease: A single-center case series

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Castleman disease is an overgrowth of lymphatic cells, usually in the chest or abdomen.

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Multicentric Castleman disease affects lymphatic cells throughout the body.

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HHV-8 and HIV have been associated with multicentric Castleman disease.

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Unicentric Castleman disease affects a single group of lymph nodes.

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Centricity is considered the most important indicator of patient outcomes.

Background

Castleman disease (CD) is a rare lymphocytic disorder. Unicentric CD (UCD) has an excellent long-term prognosis after surgical excision; however, multicentric CD (MCD) has a severe clinical course with poor outcomes.

Study design

We analyzed the clinical presentation of 28 patients treated at a single institution from 1995 to 2017. Demographics, clinical variables, anatomical site, centricity, histopathology, immunochemistry, and surgical approach were reviewed. We evaluated the 5-year recurrence and survival for patients with UCD and MCD.

Results

Of the 28 patients, 57 % (n = 16) were female, with a mean age of 41.6 ± 15.6 years. CD was asymptomatic in 57 % (n = 16) of patients, 21 % (n = 6) presented with local symptoms such as pain, and 21 % (n = 6) of patients also had systemic symptoms, including weight loss and fever. CD was unicentric in 64 % (n = 18) and multicentric in 36 % (n = 10). The hyaline vascular variant was noted in 57 % (n = 16) of the tumors, plasmacytoid variant in 36 % (n = 10), and mixed variants in 7% (n = 2) of tumors. Anatomical distributions included: head and neck (20 %), thorax and axilla (24 %), retroperitoneal (13 %), abdominopelvic (30 %) regions, and other (13 %). Complete surgical resection was performed in 95 % of patients with UCD. Surgical biopsy and medical therapy were provided to all patients with MCD. The recurrence rate for UCD and MCD was 6 % (n = 1) and 14 % (n = 1), respectively. The five-year disease-free survival rate for UCD was 95 % (n = 19) and MCD was 33 % (n = 2). We found 100 % survival in patients with UCD and histology demonstrating the HV variant.

Conclusion

CD is rare and often misdiagnosed due to the absence of specific clinical symptoms. Surgeons should include CD in their differential diagnoses when evaluating patients with lymph node hyperplasia. Surgery can be curative in nearly all patients with UCD. Patients with MCD require a combination of surgical therapy, chemotherapy, and immunotherapy; however, cytoreductive surgery benefits for patients with MCD have not been established.

Clinical and pathological characteristics of HIV- and HHV-8-negative Castleman disease

Castleman disease (CD) comprises 3 poorly understood lymphoproliferative variants sharing several common histopathological features. Unicentric CD (UCD) is localized to a single region of lymph nodes. Multicentric CD (MCD) manifests with systemic inflammatory symptoms and organ dysfunction due to cytokine dysregulation and involves multiple lymph node regions. Human herpesvirus 8 (HHV-8) causes MCD (HHV-8-associated MCD) in immunocompromised individuals, such as HIV-infected patients. However, >50% of MCD cases are HIV and HHV-8 negative (defined as idiopathic [iMCD]). The clinical and biological behavior of CD remains poorly elucidated. Here, we analyzed the clinicopathologic features of 74 patients (43 with UCD and 31 with iMCD) and therapeutic response of 96 patients (43 with UCD and 53 with iMCD) with HIV-/HHV-8-negative CD compared with 51 HIV-/HHV-8-positive patients. Systemic inflammatory symptoms and elevated inflammatory factors were more common in iMCD patients than UCD patients. Abnormal bone marrow features were more frequent in iMCD (77.0%) than UCD (45%); the most frequent was plasmacytosis, which was seen in 3% to 30.4% of marrow cells. In the lymph nodes, higher numbers of CD3⁺ lymphocytes (median, 58.88 ± 20.57) and lower frequency of CD19⁺/CD5⁺ (median, 5.88 ± 6.52) were observed in iMCD patients compared with UCD patients (median CD3⁺ cells, 43.19 ± 17.37; median CD19⁺/CD5⁺ cells, 17.37 ± 15.80). Complete surgical resection is a better option for patients with UCD. Siltuximab had a greater proportion of complete responses and longer progression-free survival (PFS) for iMCD than rituximab. Centricity, histopathological type, and anemia significantly impacted PFS. This study reveals that CD represents a heterogeneous group of diseases with differential immunophenotypic profiling and treatment response.

Update and new approaches in the treatment of Castleman disease

First described 60 years ago, Castleman disease comprises a rare and heterogeneous cluster of disorders, characterized by lymphadenopathy with unique histological features and associated with cytokine-driven constitutional symptoms and biochemical disturbances. Although unicentric Castleman disease is curable with complete surgical excision, its multicentric counterpart is a considerable therapeutic challenge. The recent development of biological agents, particularly monoclonal antibodies to interleukin-6 and its receptor, allow for more targeted disease-specific intervention that promises improved response rates and more durable disease control; however, further work is required to fill knowledge gaps in terms of underlying pathophysiology and to facilitate alternative treatment options for refractory cases.

Castleman Disease: A Rare Condition with Endocrine Manifestations

Castleman disease (CD) most commonly affects lymphoid tissues in the thorax, abdomen, pelvis, and neck. Extralymphatic tissues, such as lacrimal glands, lung, pancreas, larynx, parotid, meninges, and even muscles, have also been reported as sites. The etiology is unknown and its incidence has not been reported in the literature. Castleman disease can be classified clinically into a unicentric or multicentric form, depending on the number of lymph nodes involved, and histologically into a hyaline vascular variant, plasma cell, mixed cellular, or plasmablastic variant. The disease has a predominantly inflammatory background, reflected in high levels of vascular endothelial growth factor (VEGF) and interleukin-6 (IL-6). The role of cytokines in CD explains the clinical presentation. The clinical scenario varies widely, based mainly on the histologic type. Unicentric CD usually presents without symptomatology, whereas multicentric manifests with fatigue, abdominal or thoracic pain, cytopenias, and/or B- symptoms (10% weight loss in the last six months, nocturnal diaphoresis, and fever). The endocrinopathy has a wide range of manifestations, affecting either the pituitary or other target organs. Achieving the diagnosis is complicated and there is no laboratory or imaging pathognomonic for this disease. The gold standard is an excisional biopsy from an affected lymph node. The treatment depends on the type of CD. Unicentric CD has a good response to excisional surgery. However, in multicentric CD (MCD), surgery may provide transient relief of symptoms but with a rebound effect, so it is not considered a good method. The use of chemotherapy, monoclonal antibodies, glucocorticoids, and thalidomide has shown some improvement in MCD.

Diagnosis and management of Castleman disease

BACKGROUND

Castleman disease is an uncommon lymphoproliferative disorder characterized as either unicentric or multicentric. Unicentric Castleman disease (UCD) is localized and carries an excellent prognosis, whereas multicentric Castleman disease (MCD) is a systemic disease occurring most commonly in the setting of HIV infection and is associated with human herpesvirus 8. MCD has been associated with considerable morbidity and mortality, and the therapeutic landscape for its management continues to evolve.

METHODS

The available medical literature on UCD and MCD was reviewed. The clinical presentation and pathological diagnosis of Castleman disease was reviewed, along with associated disorders such as certain malignancies and autoimmune complications.

RESULTS

Surgical resection remains the standard therapy for UCD, while systemic therapies are required for the management of MCD. Rituximab monotherapy is the mainstay of therapy; however, novel therapies targeting interleukin 6 may represent a treatment option in the near future. Antiviral strategies as well as single-agent and combination chemotherapy with glucocorticoids are established systemic therapies. The management of Castleman disease also requires careful attention to potential concomitant infections, malignancies, and associated syndromes.

CONCLUSIONS

UCD and MCD constitute uncommon but well-defined clinicopathologic entities. Although UCD is typically well controlled with local therapy, MCD continues to pose formidable challenges in management. We address historical chemotherapy-based approaches to this disease as well as recently developed targeted therapies, including rituximab and siltuximab, that have improved the outcome for newly diagnosed patients. Ongoing research into the management of MCD is needed.

A method for generating large datasets of organ geometries for radiotherapy treatment planning studies

Background

With the rapidly increasing application of adaptive radiotherapy, large datasets of organ geometries based on the patient’s anatomy are desired to support clinical application or research work, such as image segmentation, re-planning, and organ deformation analysis. Sometimes only limited datasets are available in clinical practice. In this study, we propose a new method to generate large datasets of organ geometries to be utilized in adaptive radiotherapy.

Methods

Given a training dataset of organ shapes derived from daily cone-beam CT, we align them into a common coordinate frame and select one of the training surfaces as reference surface. A statistical shape model of organs was constructed, based on the establishment of point correspondence between surfaces and non-uniform rational B-spline (NURBS) representation. A principal component analysis is performed on the sampled surface points to capture the major variation modes of each organ.

Results

A set of principal components and their respective coefficients, which represent organ surface deformation, were obtained, and a statistical analysis of the coefficients was performed. New sets of statistically equivalent coefficients can be constructed and assigned to the principal components, resulting in a larger geometry dataset for the patient’s organs.

Conclusions

These generated organ geometries are realistic and statistically representative.

Distance deviation measure of contouring variability

BACKGROUND

Several methods that are currently used for contouring analysis have problems providing reliable and/or meaningful results. In this paper a solution to these problems is proposed in a form of a novel measure, which was developed based on requirements defined for contouring studies.

MATERIALS AND METHODS

The proposed distance deviation measure can be understood as an extension of the closest point measures in such a way that it does not measure only distances between points on contours but rather analyse deviation of distances to both/all contours from each image point/voxel. The obtained result is information rich, reliable and provided in a form of an image, enabling detailed topographic analysis. In addition to image representation, results can be further processed into angular representation for compact topographic analysis or into overall scalar estimates for quick assessment of contour disagreement.

RESULTS

Distance deviation method is demonstrated on a multi observer contouring example with complex contour shapes, i.e., with pronounced extremes and void interior. The results are presented using the three proposed methods.

CONCLUSIONS

The proposed method can detect and measure contour variation irrespective of contour complexity and number of contour segments, while the obtained results are easy to interpret. It can be used in various situations, regarding the presence of reference contour or multiple test contours.