Fludarabine treatment in resistant Waldenstrom's macroglobulinemia

Review : Purine nucleoside analogues: Fludarabine, pentostatin, and cladribine

Purpose. An introductory template for an extensive discussion of the pharmacology, pharmacokinetics, clinical use and adverse effects of the currently ap proved adenosine analogues: fludarabine, pentostatin, and cladribine is profiled. This is part one of a three-part series.

Data Sources. We reviewed the literature through a MEDLINE search from 1986 to 1996. Relevant articles cited in literature obtained by MEDLINE searching were also considered. We searched the following terms: fludarabine, cladribine, pentostatin, apoptosis and adenosine ana logues. The search was restricted to the English language. We have incorporated pricing information from our prac tice sites as well as the average wholesale price for the purpose of cost comparison.

Data Extraction. We have reviewed the current literature with regard to the chemistry, mechanisms of action and pharmacology, pharmacokinetics, clinical use, adverse effects, drug interactions, indications, formulation, dosage, administration, pharmaceutical issues and a cost comparison of the currently approved adenosine ana logues, fludarabine, pentostatin, and cladribine.

Data Synthesis. The adenosine analogues are struc turally similar agents used in the management of hemato logical malignancies. Fludarabine and cladribine exhibit significant activity in CLL (chronic lymphocytic leukemia) and NHL (non-Hodgkin's lymphoma) and pentostatin and cladribine are both active in the treatment of hairy cell leukemia. There are no comparative clinical trials between the agents and we have provided comparisons based on pharmacology, clinical experience, adverse effects and cost as well as reviewing the clinical use of these agents.

Conclusion. The adenosine analogues, fludarabine, pentostatin, and cladribine, represent an important ad vance in the treatment of indolent lymphoid malignancies. Although response rates for fludarabine and cladribine in chronic lymphocytic leukemia and for pentostatin and cladribine in hairy cell leuemia are improved over standard therapy, the true clinical impact of these agents has not yet been realized. Additional studies in larger populations of both previously treated and untreated patients, as well as comparative trials between the deoxyadenosine analogues themselves need to be carried out. Moreover, combination chemotherapy trials with deoxyadenosine analogues and other cytotoxic agents need to be performed to determine the efficacy and toxicity of these combinations in various lymphoid malignancies.

Biology, prognosis, and therapy of Waldenström Macroglobulinemia

Waldenström Macroglobulinemia (WM) is a rare B-cell lymphoma characterized by the uncontrolled accumulation of malignant lymphoplasmacytic cells, mainly in the bone marrow, and monoclonal IgM production. Despite its rarity, our understanding of the biology of this disease has improved significantly in recent years with the identification of recurrent mutations in the MYD88 and CXCR4 genes. Based on the diversity of clinical features observed in WM patients, therapy should be highly personalized having into account several factors such as age, co-morbidities, IgM levels, and presence of hyperviscosity, coagulopathy, cryoglobulinemia, or cold agglutinin disease. In this chapter, we review the recent advances in the biology of WM and the current therapeutic options for untreated and relapsed WM patients. Finally, we discuss the role of prognostic factors and current evidence supporting an improvement in the survival of WM patients in the last decade.

Current and future therapeutic approach for Waldenström's macroglobulinemia

Waldenström's macroglobulinemia is a rare B-cell malignancy defined by medullar infiltration by clonal lymphoplasmocytic cells and monoclonal IgM secretion. Treatment is reserved for symptomatic patients. The main first-line treatment strategies combine immunotherapy (principally the anti-CD20 monoclonal antibody rituximab) with chemotherapeutic agents, including alkylating agents, purine analogs and/or bortezomib. The overall response rate to these conventional treatments is between 70 and 90%, but a cure cannot be expected. For patients with relapsed or refractory disease, drugs that were not used for first-line treatment and other agents such as immunomodulators can be tried, but the response rate is generally lower and the responses are shorter lived. Recently, advances in our understanding of the biology of Waldenström's macroglobulinemia have led to the development of new drugs targeting hyperactive pathways. This review focuses on current treatment options and on new therapeutic developments.

Advances in the treatment of Waldenström’s macroglobulinemia

Waldenström's macroglobulinemia is a distinct disorder characterized by a monoclonal immunoglobulin M paraprotein and morphological evidence of lymphoplasmacytic lymphoma. It is relatively rare, accounting for approximately 2% of all hematological malignancies. The aim of treatment for patients with Waldenström's macroglobulinemia should be to improve the quality and duration of life with minimal side effects in the most cost-effective manner. It is not yet clear if achievement of a complete remission confers clinical benefit and it is possible that prolonging therapy to maximal response may increase toxicity without extra benefit. Plasma exchange is indicated for the acute management of patients with severe problems due to a circulating paraprotein. There are no comparative data but alkylating agent-based treatments, combination therapy or purine analogs are all suitable choices for the initial therapy of patients requiring treatment. In younger patients, in whom high-dose treatment is contemplated, there is a role for the use of rituximab; however, it should be administered with caution in patients with high levels of immunoglobulin M paraprotein or signs of hyperviscosity because of the risk of 'flare' in the paraprotein level and consequent adverse clinical events.

How to manage Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is very distinct from other indolent lymphoma subtypes: by definition it is accompanied by a monoclonal IgM gammopathy; it presents always with bone marrow infiltration and often with clinical symptoms such as neuropathy or hyperviscosity. These disease characteristics and the frequently advanced age of the WM patient pose a major challenge to the treating clinician even today. Recently, there has been not only substantial progress in our understanding of the biology of WM, but we have also significantly improved our tools to prognostify and to treat patients with this disease. This review summarizes our current knowledge about WM and aims at offering a guideline for the clinical management of patients with this lymphoma subtype, covering questions on how to manage diagnosis, prognostification and treatment based on the most recent data.

Fludarabine Combination Therapy Is Highly Effective in First-Line and Salvage Treatment of Patients with Waldenström's Macroglobulinemia

Alkylating agents or single-agent purine analogues are modestly effective as front-line therapy for Waldenstrom's macroglobulinemia (WM), but response rates of < 50% are exhibited in the salvage therapy setting. Fludarabine combination therapy may be more effective, but no large studies exploring these regimens specifically in WM are available. We report our results of 18 cycles of fludarabine combination therapy: FC (fludarabine 25 mg/m2 for 3 days plus cyclophosphamide 250 mg/m2 for 3 days; n = 9), FM (fludarabine 25 mg/m2 for 3 days plus mitoxantrone 10 mg/m2 for 1 day; n = 3), FCR (FC plus rituximab 375 mg/m2; n = 5), or fludarabine/rituximab (n = 1). Four patients had previously untreated disease, and 14 had pretreated disease; 67% had elevated serum levels of beta2-microglobulin, and 86% had hemoglobin levels < or = 12 g/dL. Patients received a median of 4 cycles (range, 1-6 cycles), with grade > or = 3 neutropenia and infection complicating 25% and 4% of cycles, respectively. Objective responses (all partial) were attained in 13 patients (76%). Response rates did not significantly differ by regimen, previous treatment, age, performance status, beta2-microglobulin level, hemoglobin level, time from diagnosis, previous fludarabine exposure, or alkylator refractoriness. Median remission duration was 38 months; no previously untreated patient had died at a median of 37 months of follow-up, and the actuarial 5-year survival rate was 55% for pretreated patients. No cases of secondary myelodysplasia or leukemia were encountered.

Waldenström macroglobulinemia: a review of therapy

Waldenström macroglobulinemia is a rare monoclonal gammopathy-associated lymphoplasmacytic lymphoma. Its incidence is only 4 per million per year. This review contains the known published literature specifically on the available management tools for Waldenström macroglobulinemia and is designed to assist clinicians in making management decisions for patients with this uncommon disorder.

Phase III Study of Chlorambucil Versus Fludarabine as Initial Therapy for Waldenström's Macroglobulinemia and Related Disorders

The WM1 study is a prospective randomized open-label study that includes patients with previously untreated Waldenstrom's macroglobulinemia (WM), splenic lymphoma with villous lymphocytes (SLVL), and nonimmunoglobulin (Ig) M lymphoplasmacytic lymphoma (LPL) who have an indication for treatment. At registration, patients are categorized as having WM, SLVL, or LPL, and these cohorts are to be analyzed separately. The aim of the study is to compare the efficacy of oral chlorambucil at a dose of 8 mg/m(2) (6 mg/m(2) for those > 75 years of age) for 10 days every 28 days to a maximum of 12 cycles with oral or intravenous (I.V.) fludarabine at a dose of 40 mg/m(2) orally or 25 mg/m(2) I.V. (30 mg/m(2)orally or 20 mg/m(2)I.V. for those > 75 years of age) for 5 days every 28 days to a maximum of 6 cycles. Primary endpoints are response to therapy and duration of response; secondary endpoints are improvement in hematologic parameters, toxicity of therapy, quality of life, and survival. To detect a difference in response rate of patients with WM of 15%, assuming that the overall response rates will be 50% to chlorambucil and 65% to fludarabine, with a power of 80%, requires the sample size of each group to be 183, indicating the need for collaboration among a number of national investigator groups. As of February 2005, accrual to the study stands at 143. Registration, randomization, and data collection are entirely Internet-based (www.waldenstroms.org), and the study is organized by an international collaboration, with a planned interim analysis and an external data monitoring committee.

Treatment Options in Waldenstrom's Macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is a rare chronic B-cell lymphoproliferative disorder characterized by macroglobulin (immunoglobulin M; IgM) paraproteinemia. The clinical manifestations associated with WM can be related to those of direct organ tumor infiltration, hyperviscosity and tissue deposition of IgM. Treatment must be individualized according to the nature of the clinical manifestations. Plasmapheresis has a role in patients whose symptoms are caused by increased serum viscosity. Chlorambucil was first used with response rates varying between 31% and 72% and is now probably the most commonly used oral agent. Melphalan and cyclophosphamide may have similar clinical efficacy. The addition of corticosteroids does not seem to increase response rates and the use of combination chemotherapy in the first-line setting is not recommended. Fludarabine and cladribine are cross-resistant and induce a response in 30%-60% of patients who have had prior therapy with alkylating agents and as many as 100% of previously untreated patients. Thirty-five percent to 50% of patients respond to single rituximab therapy, with limited toxicity. There are no data from prospective randomized studies to guide the choice between alkylating agents, nucleoside analogues, and rituximab for first-line therapy of WM. Autologous and allogeneic stem cell transplantation may be considered for patients with primary refractory/relapsing disease, especially in the younger age groups. Thalidomide alone or in combination with steroids/clarithromycin may be a useful salvage regimen for some heavily pretreated patients with cytopenia, even though toxicity is considerable. Splenectomy is rarely indicated.

Treatment for Waldenstrom’s macroglobulinemia

Waldenstrom's macroglobulinemia is a rare form of indolent lymphoma characterized by the production of a monoclonal immunoglobulin M protein, and complications such as hyperviscosity, cytopenias and peripheral neuropathy. Conventional treatment approaches are based on alkylators or nucleoside analogs, but in the absence of a clearly superior regimen, a broad array of alternative therapies exists. Choices range from biological agents to combination chemotherapy to stem-cell transplantation. A rational approach therefore must be based on careful patient assessment and individualization of therapy.

Waldenström macroglobulinaemia

Waldenström macroglobulinemia (WM) is a lymphoid neoplasm characterised by a monoclonal lymphoplasmacytic expansion accompanied by a serum monoclonal immunoglobulin M (IgM). In some patients, the monoclonal protein will lead to a characteristic hyperviscosity syndrome. Although indolent, WM is incurable and most patients eventually succumb to disease progression. Thus, we need to better understand the natural history and biology of the disease. Recent work has shown that half of patients with WM harbour deletions in the long arm of chromosome 6. Increasing evidence suggests the disease is a defined pathological entity and not purely a clinical syndrome. Current therapeutic modalities include alkylator agents, purine nucleoside analogues, and rituximab. The optimum initial therapeutic strategy is not yet defined, and current clinical trials are addressing the role of combination therapy. In this review, we summarise the current understanding of the pathogenesis, clinical and laboratory features, prognostic factors, and therapeutic options for patients with WM. We also discuss current knowledge of WM and available therapies.

Waldenstrom's macroglobulinemia: a retrospective analysis of 40 patients from 1972 to 2001

From 1972 to 2001 at St. Bartholomew's Hospital 40 untreated Waldenstrom's macroglobulinemia (WM) patients received either chlorambucil (n = 23); cyclophosphamide, vincristine, and prednisolone (CVP) (n = 5); fludarabine-based therapy (n = 5); or other combination chemotherapy (n = 7). Twenty-eight patients (70%) responded to first-line therapy with overall response rates as follows: chlorambucil, 17/23 (74%); CVP, 4/5 (80%); fludarabine-based regimen, 2/5 (40%); other combinations, 5/7 (71%). Twenty patients were treated at progression with chlorambucil, of whom 10 (50%) responded again, 6/13 having had chlorambucil initially, and 4/7 having had other therapy. Although there was a trend towards a survival advantage for patients who responded to chlorambucil, this difference was not statistically significant. At 6 and 11 years, overall survival was 36% v 18% and 15% v 0% for responders and nonresponders, respectively. The overall pattern was the same for patients treated initially with chlorambucil as with other therapy. This retrospective analysis confirms that chlorambucil is an effective first-line agent in WM and has activity when used at subsequent relapse.

The Wayne State University Waldenstrom's Macroglobulinemia preclinical model for Waldenstrom's macroglobulinemia

The Wayne State University Waldenstrom's Macroglobulinemia xenograft model in mice with severe combined immune deficiency (WSU-WM-SCID) is the only preclinical animal model available for this disease. It is based on a permanent, EBV- IgMlambda cell line (WSU-WM) established from a patient with a 10-year history of Waldenstrom's macroglobulinemia (WM). These cells are CD5(-)CD10(+)CD19(+)CD20(+)CD22(+) and have t(8;14) (q24;32), t(12;17) (q24;q21), 2p-. WSU-WM cells also express DNA topoisomerase II (alpha and beta), and are bcl(2)(+)bcl(XL)(+)bax(-). Although the tumor has aggressive biological behavior with c-myc-IgH rearrangement, it has retained the salient features of WM. The breakpoint on 8q24 is downstream of c-myc exon 3, which is not usual for Burkitt-type breakpoints. WSU-WM cells also express both secretory (s(u)) and membrane (m(u)) IgM mRNA and secrete IgM in culture supernatant. Histiologically, WSU-WM-SCID xenograft tumors have lymphoplasmacytoid morphology. These features indicate biological, but not histological evolution. The WSU-WM-SCID is a model of a more aggressive and resistant WM usually seen toward the late stages of disease. It is, therefore, a particularly useful tool in developing new therapeutic strategies for the more aggressive WM, including targeted therapy, which exploits unique molecular characteristics of tumor cells.

Treatment recommendations in Waldenstrom's macroglobulinemia: consensus panel recommendations from the Second International Workshop on Waldenstrom's Macroglobulinemia

This presentation represents consensus recommendations for the treatment of patients with Waldenstrom's macroglobulinemia (WM), which were prepared in conjunction with the second International Workshop held in Athens, Greece during September 2002. The faculty adopted the following statements for the management of patients with Waldenstrom's macroglobulinemia: (1) Alkylating agents, nucleoside analogues, and rituximab are reasonable choices for first line therapy of WM. (2) Both cladribine and fludarabine are reasonable choices for the therapy of WM. (3) Combinations of alkylating agents, nucleoside analogues, or rituximab should at this time be encouraged in the context of a clinical trial. (4) In WM, rituximab can cause a sudden rise in serum IgM and viscosity levels in certain patients, which may lead to complications, therefore close monitoring of these parameters and symptoms of hyperviscosity is recommended for WM patients undergoing rituximab therapy. (5) For relapsed disease, it is reasonable to use an alternate first line agent or re-use of the same agent; however, since autologous stem cell transplantation may have a role in treating patients with relapsed disease it is recommended that for patients in whom autologous transplantation is seriously being considered, exposure to alkylator or nucleoside analogue drugs should be limited. (6) Combination chemotherapy for patients who can tolerate myelotoxic therapy, thalidomide alone or with dexamethasone, can reasonably be considered to have relapsed. (7) Autologous stem cell transplantation may be considered for patients with refractory or relapsing disease. (8) Allogeneic transplantation should only be undertaken in the context of a clinical trial. (9) Plasmapheresis should be considered as interim therapy until definitive therapy can be initiated. (10) Rituximab should be considered for patients with IgM-related neuropathies. (11) Corticosteroids may be useful in the treatment of symptomatic mixed cryoglobulinemia. (12) Splenectomy is rarely indicated but has been used to manage painful splenomegaly and hypersplenism.

2-Chlorodeoxyadenosine alone and in combination for previously untreated Waldenstrom's macroglobulinemia

Treatment for Waldenstrom's macroglobulinemia (WM) has usually been reserved for symptomatic patients and has included alkylating agent-steroid combinations and, more recently, nucleoside analogues. We now describe our experience with 2-chlorodeoxyadenosine (2-CdA) alone and in combination at our center. We treated 90 consecutive, previously untreated patients with symptomatic WM using either 2-CdA alone or in combination with other agents including prednisone (pred), cyclophosphamide (Cy), and rituximab (Rit) as follows: January 1991 to December 1992- 2-CdA 0.1 mg/kg by continuous infusion (CI) over 24 hours for days (16 patients); December 1992 to December 1995-2-CdA 0.1 mg/kg CI over 24 hours for 7 days plus pred 60 mg/m(2) orally daily for 7 days (20 patients); July 1996 to March 1998-2-CdA 1.5 mg/m(2) by subcutaneous injection (SC) every 8 hours for 7 days plus Cy 40 mg/m(2) orally twice daily for 7 days (37 patients); August 1999 to December 2001-2-CdA 1.5 mg/m(2) SC every 8 hours for 7 days plus Cy 40 mg/m(2) orally twice daily for 7 days plus Rit 375 mg/m(2) by intravenous infusion (IV) weekly for 4 weeks (17 patients). For nearly all patients, a second course was repeated after at least 6 weeks. Responding patients were monitored without further treatment until relapse. Overall response (complete [CR] + partial response [PR]) was 94% for 2-CdA alone, 60% for 2-CdA/pred, 84% for 2-CdA/Cy, and 94% for 2-CdA/Cy/Rit. Median overall survival is 73 months for 2-CdA, 41 months for 2-CdA/pred, and has not been reached for 2-CdA/Cy or 2-CdA/Cy/Rit. Cause-specific survival for 2-CdA/pred is 78 months and has not been reached for all other programs. The only poor prognostic factor for cause-specific survival was hemoglobin < 9 g/dL. 2-CdA regimens provide excellent response rates and improve cause-specific survival, with minimal treatment and little toxicity. These observations support the potential role of 2-CdA regimens as the treatment of choice for previously untreated WM.

Prognostic factors and response to fludarabine therapy in Waldenstrom's macroglobulinemia: an update of a US intergroup trial (SW0G S9003)

We report an update on a prospective observational trial for Waldenstrom's macroglobulinemia (WM) that called for re-registration to treatment with fludarabine (30 mg/m(2)) upon the development of symptomatic or progressive disease. Patients who did not require therapy for more than 1 year (n = 54) could be distinguished from the 118 untreated patients requiring immediate therapy on the basis of hemoglobin, serum beta(2)-microglobulin (beta2m), C-reactive protein (CRP), albumin, and IgM levels, and lower incidence of extramedullary infiltration. Overall response rate (>or= partial response [PR]) to fludarabine was 38%, with 2% complete remissions (CRs). Event-free and overall survivals were significantly longer in the presence of lower levels of serum beta2m in all cohorts. Using time-dependent covariates, neither the occurrence of response (>or= PR) nor the time to response was associated with superior overall or event-free survival. These data support serum beta2m as the dominant prognostic indicator in WM, and show that this factor alone can provide valuable disease risk assessment. Response to therapy using current criteria is not a reliable predictor for survival in this disease.

Fludarabine in Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM), a rare B-cell malignancy, is incurable. Conventional treatment consists of alkylating agents (especially chlorambucil), with or without corticosteroids. Purine analogues such as fludarabine are also active. Response rates to first-line therapy range from 38% to 85%. Discrepancies in response rates between different studies could be due to the small patient populations in two studies and to differences in patient characteristics and response criteria. Since 1990, several phase 2 trials of purine analogues have been done with previously treated patients; fludarabine induced responses in about one third of patients who were resistant to previous treatments. Response rates to fludarabine in previously treated patients range from 30% to 50% and are highest among patients who are still sensitive to their primary therapy. The responses last from 32 to 41 months. The principal toxicity of fludarabine is myelosuppression. Trials of fludarabine combination therapy with drugs such as rituximab are ongoing.

Waldenström's macroglobulinaemia: current therapy and future approaches

Waldenström's macroglobulinaemia is a rare B-cell malignancy. It is prevalent in the sixth and seventh decades, the median age at diagnosis being 63 years. Conventional treatment has involved alkylator therapy, especially chlorambucil given daily at a low dose or intermittently at a higher dose. Purine analogues, used initially as salvage therapy in refractory disease, are increasingly used for initial therapy. However, purine analogue therapy entails significant complications, including immunosuppression, pancytopenia and autoimmune haemolysis. Moreover, it is unclear whether purine analogues extend survival. All of these need to be considered before initiation of therapy. More recently, anti-CD20 monoclonal antibody and thalidomide have been used with a 30% response in treated patients. High-dose therapy with stem cell support achieves a partial response in a majority of patients receiving this modality of therapy. The median survival of 5 years has not improved considerably since the introduction of purine analogues. Complete response is still uncommon; using all available modalities of therapy may increase the complete response rate and improve survival. Great strides in understanding the malignant cell, the microenvironment and the potential interactions have identified potential targets for therapy in multiple myeloma. These agents may also be useful in Waldenström's macroglobulinaemia. Since this is a rare malignancy, all patients should be treated with well-designed clinical protocols to achieve improvement in outcome.

Waldenström's macroglobulinaemia

Waldenström's macroglobulinaemia (WM) is most usefully defined as a distinct chronic lymphoproliferative disorder with characteristic marrow morphology and phenotype; although nodal morphology if available will reveal a lymphoplasmacytoid lymphoma, the presence of a significant IgM paraprotein defines the clinical features of the disease. The clonal cell is a B-cell expressing IgM, CD19, and CD20 but not IgD, CD5, CD10 or CD23 and has somatic hypermutation of immunoglobulin heavy chain variable regions consistent with a post-germinal centre origin. Treatment of WM has been dependent on alkylating agents with or without coriticosteroids for many years, supplemented by the use of therapeutic plasmapheresis in the initial stages for patients at risk from the clinical consequences of hyperviscosity. This approach to treatment results in response rates of approximately 60% with a median survival of about 60 months. There is increasing evidence to show that the purine analogues fludarabine and cladribine which are active in the treatment of patients who are resistant to alkylating agents such as chlorambucil may be able to achieve higher response rates when used as initial therapy. A prospective trial is being undertaken to compare fludarabine and chlorambucil as initial treatment; because of the effect of subsequent active treatment on patients who do not respond to the first treatment choice, the long-term outcome may be similar for both groups. Recent advances in therapy include the use of therapeutic monoclonal antibodies such as rituximab and the use of autologous or allogeneic transplant procedures for selected patients.

Waldenström's macroglobulinemia: a review of therapy

Waldenstrom's macroglobulinemia is a lymphoplasmacytic disorder characterized by a monoclonal IgM protein, anemia, hepatosplenomegaly, and hyperviscosity. With the increasing use of screening chemistry evaluations, many patients are diagnosed without symptoms and are candidates for observation with no therapeutic intervention until symptoms develop. Plasma exchange can be useful to manage hyperviscosity but does not address the infiltrative process in the bone marrow, which requires cytoreductive therapy. This review covers current regimens that have been used to manage Waldenstrom's macroglobulinemia, including alkylating agents, purine nucleoside analogs, and rituximab. The value of steroids, radiotherapy, stem cell transplantation, and splenectomy is also reviewed. The lack of phase III studies does not permit an algorithm that would be appropriate for all patients. Treatment needs to be individualized based on patient age, the clinical manifestations of Waldenström's, and the patient's potential for developing toxic side effects of the selected treatment regimen.

Fludarabine therapy in Waldenström's macroglobulinemia patients treated previously with 2-chlorodeoxyadenosine

Six patients with Waldenström's macroglobulinemia (WM) resistant to previous 2-chlorodeoxyadenosine (2-CdA) therapy were treated with fludarabine. Both initial and subsequent therapy was administered according to the most widely used protocols. The median number of 2-CdA cycles given to the patients was 3.7 (range 2-5), while fludarabine was 1.7 (range 1-2). As a result partial remission was achieved in two patients and stabilization of the disease in the remaining four in spite of the inadequate response or progressive disease after 2-CdA therapy. Median monoclonal IgM concentration fell from 29.4 (range 11.6-37.1) to 16.4 g/l (range 3.8-29.1). At the same time hemoglobin concentration increased from median 114 (range 89-129) to 122 g/l (range 97-133). Side effects consisted of neutropenia (three patients) and thrombocytopenia (two patients). Two patients are alive with progression of the disease noted after 12 and 21 months of observation. One patient died as the result of cardiac disease, two others died of infection 5 and 16 months after cessation of therapy in the course of disease progression. The remaining patient was lost to follow-up after 10 months of observation with continuous stabilization. Our observations suggest that in WM patients resistant to 2-CdA, stabilization of the disease or even remission can be obtained with fludarabine.

Multicenter, randomized comparative trial of fludarabine and the combination of cyclophosphamide-doxorubicin-prednisone in 92 patients with Waldenström macroglobulinemia in first relapse or with primary refractory disease

Few reports are available on the treatment of patients with Waldenström macroglobulinemia (WM) and primary or secondary resistance to alkylating-agent-based regimens. From December 1993 through December 1997, 92 patients with WM resistant to first-line therapy (42) or with first relapse (50) after alkylating-agent therapy were randomly assigned to receive fludarabine (25 mg/m(2) of body-surface area on days 1-5) or cyclophosphamide, doxorubicin (Adriamycin), and prednisone (CAP; 750 mg/m(2) cyclophosphamide and 25 mg/m(2) doxorubicin on day 1 and 40 mg/m(2) prednisone on days 1-5). The first end point evaluated was the response rate after 6 treatment courses. Forty-five patients received CAP and 45 received fludarabine. Two patients died before the first course of chemotherapy. No statistical differences were observed between the 2 treatment arms with respect to hematologic toxicity or infections. Mucositis and alopecia occurred significantly more often in patients treated with CAP. Partial responses were obtained in 14 patients (30%) treated with fludarabine and 5 patients (11%) treated with CAP (P =.019). Responses were more durable in patients treated with fludarabine (19 months versus 3 months), and the event-free survival rate was significantly higher in this group (P <.01). Forty-four patients died, 22 in the fludarabine group and 22 in the CAP group. There was no statistical difference in the median overall survival time in the 2 study arms. Fludarabine was thus more active than CAP in salvage therapy of WM and should be tested as first-line therapy in a randomized comparison with alkylating agents.

Prognostic factors and response to fludarabine therapy in patients with Waldenström macroglobulinemia: results of United States intergroup trial (Southwest Oncology Group S9003)

Current information on Waldenström macroglobulinemia (WM) is based on retrospective or single-institution studies of patients requiring therapy. Between 1992 and 1998, 231 patients with WM were enrolled in a prospective observational multicenter clinical trial. Of these, 182 patients with symptomatic or progressive disease were treated with 4 to 8 cycles of therapy with a purine nucleoside analogue, fludarabine (FAMP; 30 mg/m(2) of body-surface area daily for 5 days every 28 days). A serum beta2-microglobulin (beta2M) level below 3 mg/L and a hemoglobin level of at least 120 g/L (12 g/dL) at presentation predicted a lower likelihood of requiring therapy. The overall rate of response to FAMP therapy was 36% (95% confidence interval, 29%-44%), with 2% complete remissions. Patients who were 70 years old or older had a substantially lower likelihood of response (odds ratio, 0.34; P =.004) than younger patients. On multivariate analysis, a serum beta2M level of 3 mg/L or higher, hemoglobin level below 120 g/L, and serum IgM level below 40 g/L [4 g/dL] were significant adverse prognostic factors for survival. We developed a simple staging system for WM by using these variables and identified 4 distinct subsets of patients with estimated 5-year overall survival rates of 87%, 64%, 53%, and 22%, and 5-year progression-free survival rates of 83%, 55%, 33%, and 12%. Prognosis in WM is highly variable and serum beta2M was the dominant predictor of a need for therapy and of survival. FAMP has activity against WM. Our staging system may provide guidance for a risk-based approach to the treatment of WM.

Treatment options in Waldenström's macroglobulinaemia: the role of the purine analogues

The purine nucleoside analogues, either alone or in combination with other chemotherapeutic agents, are increasingly used in the treatment of patients with indolent B-cell lymphoproliferative disorders. The initial studies in Waldenström's macroglobulinaemia (WM) are very promising. Approximately 40% of patients who have received prior therapy with alkylating agents respond, while response rates of up to 90% have been documented in untreated patients. However, it is not known whether the purine analogues offer any significant advantage over alkylating agents such as chlorambucil. In this review the treatment options in WM and in particular the role of the purine analogues are discussed.

Waldenström's macroglobulinemia

Waldenström's macroglobulinemia (WM) is a clinical syndrome with diverse prognoses, and not all patients require therapy at diagnosis. Serum beta2 microglobulin is a major prognostic determinant, and asymptomatic patients with low beta2 microglobulin levels and preserved hemoglobin can be observed over long periods without therapy. Low-dose alkylating agents and purine analogs are commonly employed as initial therapy but rarely yield complete remissions. Patients who are refractory to or have relapse after alkylator or purine analogue therapy can be salvaged with purine analogs. Improvement in outcome demands a comprehensive approach aimed at increasing and sustaining complete remissions. Such an approach should probably employ Rituxan (IDEX Pharmaceuticals, La Jolla, CA) in conjunction with induction therapy, peripheral stem cell procurement before purine analog therapy, and high-dose therapy followed by maintenance therapy with interferon.

Waldenström's macroglobulinemia

Waldenström's macroglobulinemia is a low-grade lymphoplasmacytic lymphoma. It has an overall incidence of 2.5/million/year. The median age at diagnosis is 63 years. The clinical manifestations are hepatomegaly (20%), splenomegaly (15%), and lymphadenopathy (15%). The most common symptom is fatigue related to a normochromic, normocytic anemia, and the median hemoglobin value at diagnosis is 10 gm/dl. All patients with Waldenström's macroglobulinemia have a circulating tumor marker, the monoclonal IgM protein. Occasionally high levels of the IgM monoclonal protein can produce a hyperviscosity syndrome manifested by oronasal bleeding. Occasionally retinal hemorrhage or serious neurologic complications, such as somnolence or coma, may occur. The most important prognostic factors are hemoglobin, age, weight loss, and a cryoglobulin. Therapy has included alkylating agents, particularly chlorambucil, purine nucleoside analogs such as fludarabine or cladribine, and most recently the use of rituximab. The median survival of symptomatic patients is 65 months. Patients without symptoms should not be treated.

Delayed onset of autoimmune hemolytic anemia complicating cladribine therapy for Waldenström macroglobulinemia

Therapeutic options for patients with Waldenström macroglobulinemia (WM) now include the purine nucleoside analogues, fludarabine and cladribine. Both these agents have been associated with the onset of severe life-threatening autoimmune hemolytic anemia (AIHA) in patients with chronic lymphocytic leukemia (CLL). In these reports, AIHA developed within 6 weeks of drug administration and was generally resistant to conventional therapy. AIHA following purine analogues has not been reported in other hematologic malignancies. We report here on 4 patients with WM who developed AIHA following cladribine therapy. Cladribine was administered as a 2-hour infusion at a dose of 0.12 mg/kg per day for 5 consecutive days, at 28-day intervals. The median number of cycles was four (range, 4 to 6). AIHA occurred at a median of 40 months (range, 24 to 60) from cladribine administration. Only 1 patient responded to oral steroids while the other 3 were resistant to multiple therapeutic interventions. Two patients, 1 in complete remission and 1 requiring transfusional support, remain alive, and 2 have died. In contrast to published reports of the early onset of AIHA occurring after purine analogues in CLL patients, we observed AIHA in WM patients as a delayed event.

Waldenström's macroglobulinemia: clinical features, complications, and management

PURPOSE

To review the clinical features, complications, and treatment of Waldenström's macroglobulinemia, a low-grade lymphoproliferative disorder that produces monoclonal immunoglobulin (Ig) M.

METHODS

A review of published reports was facilitated by the use of a MEDLINE computer search and by manual search of the Index Medicus.

RESULTS

The clinical manifestations associated with Waldenström's macroglobulinemia can be classified according to those related to direct tumor infiltration, to the amount and specific properties of circulating IgM, and to the deposition of IgM in various tissues. Asymptomatic patients should be followed without treatment. For symptomatic patients, standard treatment consists primarily of oral chlorambucil; nucleoside analogs, such as fludarabine and cladribine, are effective in one third of previously treated patients and in up to 80% of previously untreated patients. Preliminary evidence suggests that anti-CD20 monoclonal antibody may be active in about 30% of previously treated patients and that high-dose therapy with autologous stem-cell rescue is effective in most patients, including some with resistance to nucleoside analogs.

CONCLUSION

Waldenström's macroglobulinemia has a wide clinical spectrum that practicing physicians need to recognize early to reach the correct diagnosis. When therapy is indicated, oral chlorambucil is the standard primary treatment, but cladribine or fludarabine can be used when a rapid cytoreduction is desirable. Prospective randomized trials are required to elucidate the impact of nucleoside analogs on patients' survival. A nucleoside analog is the treatment of choice for patients who have been previously treated with an alkylating agent.

Waldenström's macroglobulinemia

Waldenström's macroglobulinemia is an unusual low-grade lymphoplasmacytic lymphoma characterized by the production of monoclonal IgM. The clinical manifestations associated with WM can be classified as those related to direct tumor infiltration, by the amount and specific properties of circulating IgM, and by the deposition of IgM in various tissues. Asymptomatic patients should be followed without treatment. The management of the disease relies on the administration of systemic chemotherapy to reduce tumor load and on the application of plasmapheresis to remove circulating IgM. Standard treatment consists of oral chlorambucil, which induces response in at least 50% of patients, resulting in a median survival of approximately 5 years. Nucleoside analogues (cladribine, fludarabine) are effective in most previously untreated patients. These agents are the treatment of choice for patients with disease resistant to alkylating agents. New treatment approaches include high-dose therapy with stem-cell support and administration of monoclonal anti-CD20 antibodies.

High-dose therapy with autologous haemopoietic stem cell support for Waldenström's macroglobulinaemia

Standard doses of alkylating agents or purine analogues effect response rates of up to 50% in Waldenström's macroglobulinaemia (WM); however, complete responses are infrequent and there are no cures. We have evaluated the feasibility, safety and efficacy of high-dose chemotherapy with peripheral blood stem cell support in six patients aged 45-69 years (median 51.5) with WM; four patients relapsed after prior therapy inclusive of purine analogues and two patients proceeded with transplant after minimal therapy. Four patients mobilized adequate numbers of stem cells; however, two patients with more extensive fludarabine therapy failed to mobilize and required a second attempt at stem cell collection. Five patients were treated with melphalan 200 mg/m2, including one patient who received tandem transplants and one patient who received melphalan 140 mg/m2 with added total body irradiation (TBI). There was no treatment-related mortality and non-haematological toxicities were manageable. Engraftment was prompt except in one patient with extensive prior use of fludarabine. All the six patients achieved at least partial response (PR), including one who achieved complete response (CR). Five patients are alive and four are event-free at 52+, 15+, 12+ and 2+ months post transplant. This pilot study suggests safety and efficacy of high-dose therapy in WM and suggests that the peripheral blood stem cells should preferably be procured prior to extensive use of purine analogues.

Bolus administration of cladribine in the treatment of Waldenström macroglobulinaemia

This phase II clinical trial evaluated bolus cladribine as a single agent in Waldenstrom macroglobulinaemia (WM). Cladribine was administered to 20 patients at a dose of 0.12 mg/kg/d by 2 h intravenous infusion for 5 consecutive days at monthly intervals for three courses. Partially responding patients were continued on therapy until maximal response and/or prohibitive toxicity, to a maximum of eight courses. Complete responders were treated with one additional course of cladribine. After a median of three courses of cladribine, all 20 patients were evaluable; one achieved a complete response (CR) (5%) and 10 achieved a partial response (PR) (50%). The median duration of response follow-up was 28 months (range 1-37 months). Four of 7 (57%) untreated and 7/13 (54%) previously treated patients responded. The major toxicity encountered was myelosuppression with 60% of patients demonstrating grade 3 or 4 neutropenia. Non-haematological toxicities included two patients with herpes zoster and two patients with non-melanoma skin cancers. At a median follow-up duration of 20 months, 17 patients remain alive and three have died. We confirm that bolus cladribine is an effective and safe method of drug delivery in WM patients. Recommendations regarding the equivalence of the continuous infusion and bolus methods in untreated patients requires further study. Bolus cladribine is more convenient and less costly than infusional cladribine since it obviates the need for central catheters and infusional devices.

Cryptococcal meningitis and intracranial tuberculoma in a patient with Waldenstrom's macroglobulinemia treated with fludarabine

We report a patient with Waldenstrom's Macroglobulinemia who presented with cryptococcal meningitis followed by an intracranial tuberculoma during the 18 months period after termination of cytotoxic therapy with Fludarabine. Opportunistic infections due to intracellular organisms are extremely rare in the course of this malignancy and we review the predisposing factors of these infectious entities.