2-Chloro-deoxyadenosine therapy for giant lymph node hyperplasia

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.

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.

Castleman's disease: from basic mechanisms to molecular therapeutics

Castleman's disease is a rare lymphoproliferative disorder in which there has been recent progress in elucidating underlying mechanisms with potential therapeutic implications. Unicentric Castleman's disease is an indolent condition that is often treated with local approaches. In contrast, patients with multicentric Castleman's disease (MCD) have a less favorable prognosis and require systemic treatment. Cytotoxic chemotherapy, with its attendant risk for toxicity, has been widely used to treat MCD, with variable efficacy. The discovery of putative etiologic factors and targets in MCD, particularly human herpes virus 8, CD20, and interleukin (IL)-6, has been translated into the use of rituximab and anti-IL-6-based therapy, as well as antiviral agents. In this article, we review the current state of the art of our understanding of Castleman's disease and its treatment and we provide insight into future treatment strategies based on disease biology.

Treatment of Castleman's disease

Castleman's disease (CD) was first described in 1954 and further defined in 1956 by Castleman. Since then much has been learned about the heterogeneity of this condition. Subsequently, three pathologic classifications have been developed (hyaline vascular variant, plasma cell variant, and mixed variant) and two clinical classifications (unicentric [unifocal or localized] and multicentric [multifocal or generalized]). The pathology found with the unicentric presentation is most commonly that of the HV variant. It responds well to surgical resection and is associated with a benign course. The multicentric presentation is rarely composed of lymph nodes with HV pathology, but rather with the plasma cell or mixed pathology. This presentation requires systemic therapy and prognosis is guarded. Associated systemic symptoms are common. There is an increased incidence of CD in patients with HIV. The human herpes virus-8 is associated with nearly all of the HIV-associated CD cases and nearly 50% of non-HIV cases. Interleukin (IL)-6 has also been shown to play a significant role in the pathogenesis of the disease. Paraneoplastic and autoimmune entities are not uncommon in the disorder. Variable benefit has been achieved with single agent chemotherapy, combination chemotherapy, interferon (IFN)-alpha, rituximab, anti-IL-6 receptor antibodies, and thalidomide. Patients with CD are at increased risk for developing frank malignant lymphoma.

[Castleman's disease in patients infected with HIV]

PURPOSE

Castleman's disease is a polyclonal lymphoplasmacytic and vascular proliferation prominant in lymphoid tissues. It is associated with lymph node enlargement, hepatosplenomegaly and fever. This manifestations could be secondary to hyperproduction of interleukin 6. The prognosis is poor. The opportunistic infections which are characteristic of severe HIV infection worsen the prognosis. Prolonged monochemotherapy with vinblastine or etoposide can control Castleman's disease.

CURRENT KNOWLEDGE AND KEY POINTS

Recent advances in human herpesvirus 8 (HHV8) knowledge and its predominance in the forms which are linked to the HIV seropositivity have partly explained the clinical manifestations of Castleman's disease. Indeed, HHV8 produce an homologous interleukin 6, the vIL-6, responsible for lymphoplasmacytic proliferation. The presence of other homologues of human cytokines produced by HHV8 could contribute to lymphoplasmacytosis and to endothelial proliferation.

FUTURE AND PROSPECTS

Taking into account this viral origin, alpha interferon could be an alternative in forms which are less progressive. However, antiviral therapy against HHV8 or HIV and the immunitary restoration do not have any influence on the evolution of Castleman's disease, contrary to opportunistic infections.

Multicentric Castleman disease and systemic lupus erythematosus phenotype in a boy with Klinefelter syndrome: long-term disease stabilization with interferon therapy

An 11-year-old boy with Klinefelter syndrome had Castleman disease (CD) of plasma cell type develop. Nonregulated antibody production mimicked systemic lupus erythematosus (SLE). Hepatitis C virus (HCV) infection caused significant disease worsening. The patient was treated with a daily dosage of 2 million units/m2 of IFN-alpha. Dramatic clinical improvement and decreasing autoimmune phenomenon were observed. HCV RNA were cleared. Hypergammaglobulinemia did not change. The boy has been living for 8 years with his disease. Plasma cell type CD can mimic collagenosis. Disease worsening is caused by HCV, though it can be reversed with IFN-alpha. Klinefelter syndrome may be a genetic susceptibility factor for CD in some cases.

Treatment of multicentric Castleman's disease complicated by the development of non-Hodgkin's lymphoma with high-dose chemotherapy and autologous peripheral stem-cell support

BACKGROUND

Castleman's disease or angiofollicular lymph node hyperplasia is a rare entity with a localized/unicentric or a generalized/multicentric presentation. While surgery is curable for most localized presentations, there is limited information regarding the optimal management of the multicentric type. The latter type is associated with a poor prognoses and can be associated with the development of lymphoma and infections.

PATIENTS AND METHODS

In this report we describe a case of multicentric Castleman's disease who failed steroids and chemotherapy and developed a follicular mixed lymphoma. He was treated with high-dose chemotherapy with autologous stem-cell support and remains disease at four years of follow-up.

CONCLUSIONS

A long-term durable remission may be possible with high dose chemotherapy with stem-cell support. This treatment modality should be considered an option in the management of multicentric Castleman's disease.

[Castleman's disease]

Castleman's disease, also called angiofollicular lymph node hyperplasia was first described as a distinct entity by Castleman et al in 1956. Two forms are now described a localized and a multicentric. The clinical and biological signs are varied and heterogeneous, and the diagnostic is made on the histologic examination. This atypical lymphoproliferative disorder is of unknown origin, but interleukin 6 play a central part in this disease. Despite the benignity of this "prelymphoma state", an aggressive course with poor prognosis occur usually in the multicentric form. Malignant lymphomas and Kaposi's sarcoma have been associated with Castleman's disease.

2-chloro-2'-deoxyadenosine: clinical applications in hematology

The anticancer drug 2-chloro-2'-deoxyadenosine (CdA) belongs to the family of purine nucleoside analogs. CdA is exquisitely cytotoxic both to the dividing and to the non-dividing lymphocyte, which supports its use in lymphoproliferative disorders of low-grade malignancy. Indeed, the best clinical results with CdA are achieved in hairy-cell leukemia, in chronic lymphocytic leukemia, in Waldenström's macroglobulinemia and in low-grade malignant lymphoma. Most patients with hairy-cell leukemia achieve a complete response with a single course of CdA. However, the disease is not eradicated and a fraction of complete responders will eventually relapse. In chronic lymphocytic leukemia and in malignant lymphoma, complete or partial responses can be achieved in approximately 40% of previously treated patients, even after classical chemotherapy has failed. However, few responses sustain beyond 1 to 2 years, while longer unmaintained responses may be obtained in Waldenström's macroglobulinemia. More responses (70-80%) are achieved in patients with chronic lymphoproliferative disorders treated de novo with CdA but their impact on survival remains to be established. More than 10 years after its first use in clinical practice, late adverse consequences of the severe and sustained immunosuppression induced by CdA have not been reported but should still be closely monitored.