Transplantation in Waldenstrom's macroglobulinemia--the French experience

Current approach to Waldenström macroglobulinemia

Waldenström macroglobulinemia (WM) is a unique CD20+, B-cell non-Hodgkin lymphoma, characterized by lymphoplasmacytic infiltration of the bone marrow and circulating monoclonal immunoglobulin M. The clinical manifestations and outcomes of patients are highly variable. High-level evidence supports integration of monoclonal anti-CD20 antibody, rituximab, to the chemotherapy backbone to treat WM. However, its contemporary management has become more nuanced, with deeper understanding of the pathophysiology and incorporation of Bruton's tyrosine kinase (BTK) inhibitors to the treatment paradigm. Prior knowledge of the patients' MYD88L265P and CXCR4 mutation status may aid in the treatment decision-making. Currently, the two frequently utilized approaches include fixed-duration chemoimmunotherapy and BTK inhibitor-based continuous treatment until progression. Randomized trials comparing these two vastly divergent approaches are lacking. Recent studies demonstrating efficacy of B cell lymphoma-2 (BCL2) inhibitors and non-covalent BTK inhibitors in patients, previously exposed to a covalent BTK inhibitor, are a testament to the rapidly expanding options against WM.

Treatment of relapsed and refractory Waldenstrom Macroglobulinemia

Waldenström's Macroglobulinemia (WM) is a rare type of indolent non-Hodgkin lymphoma (NHL) that remains incurable. Several effective agents such as monoclonal antibodies (in combination with chemotherapy), Bruton's tyrosine kinase inhibitors, proteasome inhibitors, and BCL2 inhibitors are (becoming) available for the treatment of relapsed and refractory WM. There is however no consensus on a preferred treatment in the relapsed setting. Choice of therapy in relapsed WM should be individualized by taking several treatment and patients characteristics into account, such as treatment duration, toxicity, age, comorbidities and MYD88^L265P and CXCR4 mutational status. Due to better understanding of WM biology and the arrival of novel anti-lymphoma agents, the therapeutic options are increasing. Non-cytotoxic and fixed duration regimens, such as those explored in other indolent NHLs should be the focus of future clinical trials in WM.

First-Line Treatment of Waldenström’s Macroglobulinaemia: Considerations Based on the Dutch National Guideline

Waldenström macroglobulinemia (WM) is a rare B-cell Non-Hodgkin Lymphoma. There are only few prospective randomized clinical trials to guide treatment recommendations and there is no international consensus on a preferred first line treatment approach. In the recently revised Dutch guideline for WM, we describe recommendations for practice based as much as possible on the known data. Here, we summarize the considerations for first-line treatment based on these Dutch guidelines. Available evidence is summarized, including efficacy and toxicity data. Combinations of Rituximab with chemotherapy, proteasome inhibition or BTK-inhibition are all valid first line treatment options. The Dutch WM working group considers Dexamethasone/Rituximab/Cylofosfamide (DRC) a suitable first-line treatment for many WM patients, given the efficacy, the relatively mild toxicity profile and the extensive experience with this regimen. However, the long-term toxicities of DRC are unclear and need further clarification. Other regimens such as R-bendamustine, R-Bortezomib-dexamethason are also effective options, however with specific toxicities. BTK-inhibitors are not a preferred option in first line for most patients in the Dutch WM guidelines because of the need for longterm treatment and toxicities. Based on patient preferences research, future clinical trials should focus on effective fixed-duration regimens with non-cytotoxic therapies that have a favorable toxicity profile. Further development of (combinations with) BCL-2 inhibititors, novel proteasome inhibitors and BTK-inhibition could be interesting. In addition T-cell-directed treatments including bispecific antibodies as a monotherapy or combined with other novel agents deserve further study in WM.

Diagnosis and management of Waldenström macroglobulinaemia-A British Society for Haematology guideline

SCOPE

The objective of this guideline is to provide healthcare professionals with clear guidance on the management of patients with Waldenström macroglobulinaemia. In individual patients, circumstances may dictate an alternative approach.

METHODOLOGY

This guideline was compiled according to the British Society for Haematology (BSH) process at http://www.b-s-h.org.uk/guidelines/proposing-and-writing-a-new-bsh-guideline/. Recommendations are based on a review of the literature using Medline, Pubmed, Embase, Central, Web of Science searches from beginning of 2013 (since the publication of the previous guidelines) up to November 2021. The following search terms were used: Waldenström('s) macroglobulin(a)emia OR lymphoplasmacytic lymphoma, IgM(-related) neuropathy OR cold h(a)emagglutinin disease OR cold agglutinin disease OR cryoglobulin(a)emia AND (for group a only) cytogenetic OR molecular OR mutation OR MYD88 OR CXCR4, management OR treatment OR transfusion OR supportive care OR plasma exchange OR plasmapheresis OR chemotherapy OR bendamustine OR bortezomib OR ibrutinib OR fludarabine OR dexamethasone OR cyclophosphamide OR rituximab OR everolimus, bone marrow transplantation OR stem cell transplantation. The Grading of Recommendations Assessment, Development and Evaluation (GRADE) nomenclature was used to evaluate levels of evidence and to assess the strength of recommendations. The GRADE criteria can be found at http://www.gradeworkinggroup.org. Review of the manuscript was performed by the British Society for Haematology (BSH) Guidelines Committee Haemato-Oncology Task Force, the BSH Guidelines Committee and the Haemato-Oncology sounding board of BSH. It was also on the members section of the BSH website for comment. It has also been reviewed by UK Charity WMUK; these organisations do not necessarily approve or endorse the contents.

Efficacy of Autologous and Allogeneic Hematopoietic Cell Transplantation in Waldenström Macroglobulinemia: A Systematic Review and Meta-analysis

INTRODUCTION

Waldenström macroglobulinemia (WM) is an IgM-producing lymphoproliferative disorder that remains incurable. Patients with high-risk disease have an overall survival (OS) of less than 3 years. Both autologous (AHCT) and allogeneic (allo-HCT) hematopoietic cell transplantation (HCT) are prescribed for treatment of WM despite a lack of randomized controlled studies.

MATERIALS AND METHODS

We performed a comprehensive literature search using PubMed/Medline and EMBASE on September 10, 2019. Data on clinical outcomes related to benefits and harms was extracted independently by 3 authors. Fifteen studies (8 AHCT [n = 278 patients], 7 allo-HCT [n = 311 patients]) were included in this systematic review/meta-analysis.

RESULTS

Pooled OS, progression-free survival (PFS), and nonrelapse mortality (NRM) rates post AHCT were 76% (95% confidence interval [CI], 65%-86%), 55% (95% CI, 42%-68%), and 4% (95% CI, 1%-7%), respectively. Pooled OS, PFS, and NRM rates post allografting were 57% (95% CI, 50%-65%), 49% (95% CI, 42%-56%), and 29% (95% CI, 23%-34%), respectively. OS and PFS rates were reported at 3 to 5 years, and NRM was reported at 1 year in most studies. Pooled ORR (at day 100) post AHCT and allo-HCT were 85% (95% CI, 72%-94%) and 81% (95% CI, 69%-91%), respectively. Pooled complete response rates post AHCT and allo-HCT were 22% (95% CI, 17%-28%) and 26% (95% CI, 7%-50%), respectively. Relapse rates post AHCT and allo-HCT were 42% (95% CI, 30%-55%) and 23% (95% CI, 18%-28%), respectively.

CONCLUSIONS

Our results show that both AHCT and allo-HCT are effective in the treatment of WM. A 2-fold lower relapse rate but a 7-fold higher NRM was noted for allo-HCT compared with AHCT. The role of transplant in WM needs to be addressed in the era of novel agents.

Outcome of stem cell transplantation for Waldenström's macroglobulinemia: analysis of the Japan Society for Hematopoietic Cell Transplantation (JSHCT) Lymphoma Working Group

The role of stem cell transplantation (SCT) for patients with Waldenström's macroglobulinemia (WM) remains undetermined. Therefore, we retrospectively evaluated the outcome of autologous and allogeneic SCT for patients with WM using the registry database of the Japan Society for Hematopoietic Cell Transplantation. Forty-six patients receiving autologous and 31 receiving allogeneic SCT were analyzed. The allogeneic SCT group included more patients with advanced disease status at transplant and received more lines of chemotherapy. The cumulative incidences of non-relapse mortality (NRM) at 1 year were 30.0% (95% CI, 14.7-46.9%) in the allogeneic SCT and 0% in the autologous SCT group. The estimated 3-year overall (OS) and progression-free (PFS) survival rates were 84.5% (95% CI, 66.0-93.4%) and 70.8% (95% CI, 53.0-82.9%) in the autologous SCT group, and 52.2% (95% CI, 32.5-68.6%) and 45.0% (95% CI, 26.3-62.0%) in the allogeneic SCT group. No patients died after the first 2 years following allogeneic SCT. In univariate analyses, disease status at SCT was significantly associated with PFS in autologous SCT, and with OS and PFS in allogeneic SCT. These results suggest that both autologous and allogeneic SCT have each potential role in WM. Allogeneic SCT is more curative for WM, but is associated with high NRM.

High-Dose Therapy and Hematopoietic Stem Cell Transplantation in Waldenström Macroglobulinemia

Waldenström macroglobulinemia (WM) is an indolent low-grade non-Hodgkin lymphoma characterized by bone marrow infiltration by lymphoplasmacytic cells and associated clonal IgM paraproteinemia. Recent insights into the biology and genomic characteristics of WM have provided a further platform for more targeted therapies. Despite the high response rates and better depth and duration of responses, the disease remains incurable. This review focuses on use of the high-dose therapy with either autologous or allogeneic hematopoietic stem cell transplantation.

Allogeneic Transplantation for Relapsed Waldenström Macroglobulinemia and Lymphoplasmacytic Lymphoma

Waldenström macroglobulinemia/lymphoplasmacytic lymphoma (WM/LPL) is characterized by lymphoplasmacytic proliferation, lymph node and spleen enlargement, bone marrow involvement, and IgM production. Treatment varies based on the extent and biology of disease. In some patients, the use of allogeneic hematopoietic cell transplantation (alloHCT) may have curative potential. We evaluated long-term outcomes of 144 patients who received adult alloHCT for WM/LPL. Data were obtained from the Center for International Blood and Marrow Transplant Research database (2001 to 2013). Patients received myeloablative(n = 67) or reduced-intensity conditioning (RIC; n = 67). Median age at alloHCT was 53 years, and median time from diagnosis to transplantation was 41 months. Thirteen percent (n = 18) failed prior autologous HCT. About half (n = 82, 57%) had chemosensitive disease at the time of transplantation, whereas 22% had progressive disease. Rates of progression-free survival, overall survival, relapse, and nonrelapse mortality at 5 years were 46%, 52%, 24%, and 30%, respectively. Patients with chemosensitive disease and better pretransplant disease status experienced significantly superior overall survival. There were no significant differences in progression-free survival based on conditioning (myeloablative, 50%, versus RIC, 41%) or graft source. Conditioning intensity did not impact treatment-related mortality or relapse. The most common causes of death were primary disease and graft-versus-host disease (GVHD). AlloHCT yielded durable survival in select patients with WM/LPL. Strategies to reduce mortality from GVHD and post-transplant relapse are necessary to improve this approach.

The role of stem cell transplantation in Waldenstrom's macroglobulinemia

Waldenstrom's macroglobulinemia (WM) is an indolent B-cell lymphoma, which is highly chemosensitive, with an overall response rate over 90% to novel agents. However, most patients eventually relapse after response to first-line chemotherapy, necessitating further treatment. The possibility of long-lasting remission after high-dose cytotoxic chemotherapy followed by stem cell rescue is high in WM due to the chemosensitive nature of the disease and lower proliferative activity compared to multiple myeloma. In this paper, we have reviewed current evidence on autologous (auto-) and allogeneic (allo-) stem cell transplantation (SCT) in WM. Auto-SCT can be safely performed in WM and is recommended as second-line treatment or beyond in eligible patients. It is associated with extremely low transplant-related mortality. Allo-SCT is effective in WM with incremental benefit due to graft-versus-WM effect, but is associated with high non-relapse mortality of 30%, hence should be preferably considered investigational as part of clinical trials in selected patients who have exhausted other treatment options.

Waldenstrom Macroglobulinemia: Genomic Aberrations and Treatment

Waldenström macroglobulinemia (WM) is a rare, indolent, and monoclonal immunoglobulin M-associated lymphoplasmacytic disorder with unique clinicopathologic characteristics. Over the past decade, remarkable progress has occurred on both the diagnostic and therapeutic fronts in WM. A deeper understanding of the disease biology emanates from the seminal discoveries of myeloid differentiation primary response 88 (MYD88) L265P somatic mutation in the vast majority of cases and C-X-C chemokine receptor, type 4, mutations in about a third of patients. Although WM remains an incurable malignancy, and the indications to initiate treatment are largely unchanged, the therapeutic armamentarium continues to expand. Acknowledging the paucity of high-level evidence from large randomized controlled trials, herein, we evaluate the genomic aberrations and provide a strategic framework for the management in the frontline as well as the relapsed/refractory settings of symptomatic WM.

Waldenström macroglobulinemia: What a hematologist needs to know

Waldenström macroglobulinemia (WM) is a distinct hematologic malignancy characterized by a lymphoplasmacytic bone marrow infiltration and the presence of immunoglobulin (Ig)M monoclonal protein. Patients typically present at an advanced age, and a substantial proportion are asymptomatic at diagnosis. A unifying diagnosis of WM may be missed by an unsuspecting hematologist, as symptomatic patients present with a multitude of non-specific manifestations. Although constitutional and neuropathy-related symptoms predominate, concomitant IgM-induced hyperviscosity-associated features can provide useful diagnostic clues. There are specific indications for initiation of therapy. This review focuses on the most up-to-date management strategies of WM, in addition to highlighting the recent discoveries of MYD88 and CXCR4 mutations that have shed unprecedented light on the complex signaling pathways, and opened avenues for novel therapeutic targeting. Although WM remains incurable, with the rapid emergence and integration of effective novel therapies, its clinical course appears poised to improve in the foreseeable future.

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.

Reappraising the role of autologous transplantation for indolent B-cell lymphomas in the chemoimmunotherapy era: is it still relevant?

The role of autologous hematopoietic cell transplantation (auto-HCT) in the management of indolent non-Hodgkin lymphomas (NHL) is shrouded in controversy. The outcomes of conventional therapies for many indolent lymphoma subtypes have dramatically improved over the last several years with the use of monoclonal antibodies, maintenance therapy programs and with the incorporation of radio-immunoconjugates. These significant advances in the armamentarium of lymphoma therapeutics warrant reappraisal of the current role of auto-HCT in the treatment algorithm of indolent NHL. Prospective randomized studies comparing contemporary chemoimmunotherapies against auto-HCT are lacking, leading to significant debate about the role and timing of auto-HCT for indolent NHL in the modern era. Although autografting for follicular lymphoma (FL) in first remission has been largely abandoned, it remains a useful modality for relapsed disease, especially for the subgroup of patients who are not candidates for allogeneic transplantation with a curative intent. Auto-HCT can provide durable disease control in chemosensitive transformed FL and mantle cell lymphoma (MCL) in first remission, with relatively low toxicity, and remains appropriate in chemoimmunotherapy era. Contemporary data are also reviewed to clarify the often underutilized role of autografting in relapsed MCL and other less frequent indolent NHL histologies. The biological basis of the increased risks of second malignancies with auto-HCT are reviewed to identify strategies designed to mitigate this risk by, for example, avoiding exposure to genotoxic agents, planning early stem cell collection/cryopreservation and minimizing the use of TBI with transplant conditioning, and so on. Genetic testing able to identify patients at high risk of therapy-related complications and novel post-transplant immune therapies with the potential of transforming autografting in indolent NHL from a remission-extending therapy to a curative modality are discussed to examine the possibly expanding role of auto-HCT for lymphoid malignancies in the coming years.

Allogeneic stem-cell transplantation in patients with Waldenström macroglobulinemia: report from the Lymphoma Working Party of the European Group for Blood and Marrow Transplantation

PURPOSE

Allogeneic stem-cell transplantation (alloSCT) is a curative therapeutic option for patients with low-grade lymphoid malignancies. Information regarding alloSCT in Waldenström macroglobulinemia (WM) is limited. This study presents the long-term outcome of a large series of patients with WM treated with alloSCT.

PATIENTS AND METHODS

A total of 86 patients received allograft by using either myeloablative (MAC; n = 37) or reduced-intensity conditioning (RIC; n = 49) regimens and were retrospectively studied. The median age was 49 years (range, 23 to 64 years); 47 patients had received three or more previous lines of therapy, and eight patients had experienced failure on a prior autologous stem-cell transplantation. A total of 59 patients (68.6%) had chemotherapy-sensitive disease at the time of alloSCT. Median follow-up of the surviving patients was 50 months (7 to 142 months).

RESULTS

Nonrelapse mortality (NRM) at 3 years was 33% for MAC and 23% for RIC. The overall response rate was 75.6%. The relapse rates (RRs) at 3 years were 11% for MAC and 25% for RIC. Fourteen patients received donor lymphocyte infusions (DLIs) for disease relapse. PFS and OS at 5 years were 56% and 62% for MAC and 49% and 64% for RIC, respectively. The occurrence of chronic graft-versus-host disease (cGVHD) was associated with a higher NRM and a lower RR, leading to an improvement in PFS.

CONCLUSION

alloSCT can induce durable remissions in a selected population of young and heavily pretreated patients with WM. The low RR, the achievement of additional disease responses after DLIs, and the lower RR in patients developing cGVHD suggest the existence of a clinically relevant graft-versus-WM effect.

[Waldenström's macroglobulinemia]

Waldenström's macroglobulinemia (WM) is a B-cell disorder characterized primarily by bone marrow infiltration with lymphoplasmacytic cells, along with the presence of an IgM monoclonal gammopathy in the blood. WM remains incurable with a median of 8-year of overall survival for patients with symptomatic WM. Treatment is postponed for asymptomatic patients and progressive anemia is the most common indication for initiation of treatment. The main therapeutic options include alkylating agents, nucleoside analogues, and rituximab, either alone or in combination. Studies involving new combination chemotherapy are ongoing and preliminary results are encouraging. However, there are several limitations to these approaches. The complete response rate is low and the treatment free survival is short in many patients, no specific agent or regimen has been shown to be superior to another, and no treatment has been specifically approved for WM. As such, new therapeutic agents are needed for the treatment of WM. In ongoing efforts, we and others have sought to exploit advances made in the understanding of the biology of WM so as to better target therapeutics for this malignancy. These efforts have led to the development of proteasome inhibitors as bortezomib, several Akt/mTor inhibitors, such as perifosine and Rad001. Many other agents and monoclonal antibodies are currently being tested in clinical trials and seem promising. This article provides an update of the current preclinical studies and clinical efforts for the development of novel agents in the treatment of WM.

Allogeneic hematopoietic stem cell transplantation allows long-term complete remission and curability in high-risk Waldenström’s macroglobulinemia. Results of a retrospective analysis of the Société Française de Greffe de Moelle et de Thérapie Cellulaire

BACKGROUND

Patients with poor-risk Waldenström's macroglobulinemia have suboptimal response and early post-treatment relapse with conventional therapies. Hence, new therapeutic approaches such as allogeneic stem cell transplantation should be evaluated in these patients.

DESIGN AND METHODS

We examined the long-term outcome of allogeneic stem cell transplantation in Waldenström's macroglobulinemia by studying the records of 24 patients reported in the SFGM-TC database and one transplanted in the bone marrow unit in Hamburg.

RESULTS

Median age at the time of transplant was 48 years (range, 24-64). The patients had previously received a median of 3 lines of therapy (range, 1-6) and 44% of them had refractory disease at time of transplant. Allogeneic stem cell transplantation after myeloablative (n=12) or reduced-intensity (n=13) conditioning yielded an overall response rate of 92% and immunofixation-negative complete remission in 50% of evaluable patients. With a median follow-up of 64 months among survivors (range, 11-149 months), 5-year overall survival and progression-free survival rates were respectively, 67% (95% CI: 46-81) and 58% (95% CI: 38-75). The 5-year estimated risk of progression was 25% (95% CI: 10-36%), with only one relapse among the 12 patients who entered complete remission, versus 5 in the 12 patients who did not. Only one of the 6 relapses occurred more than three years post-transplant.

CONCLUSIONS

Allogeneic stem cell transplantation yields a high rate of complete remissions and is potentially curative in poor-risk Waldenström's macroglobulinemia.

Update on therapeutic options in Waldenström macroglobulinemia

Waldenström macroglobulinemia (WM) is a B-cell disorder characterized primarily by bone marrow infiltration with lymphoplasmacytic cells (LPCs), along with demonstration of an IgM monoclonal gammopathy in the blood. WM remains incurable, with 5-6 yr median overall survival for patients with symptomatic WM. The main therapeutic options include alkylating agents, nucleoside analogues, and rituximab, either in monotherapy or in combination. Studies involving combination chemotherapy are ongoing, and preliminary results are encouraging. However, there are several limitations to these approaches. The complete response rate is low and the treatment free survival are short in many patients, no specific agent or regimen has been shown to be superior to another, and no treatment has been specifically approved for WM. As such, novel therapeutic agents are needed for the treatment of WM. In ongoing efforts, we and others have sought to exploit advances made in the understanding of the biology of WM so as to develop new targeted therapeutics for this malignancy. These efforts have led to the development of proteasome inhibitors, of them bortezomib, several Akt/mTor inhibitors, such as perifosine and Rad001, and immunomodulatory agents such as thalidomide and lenalidomide. Many agents and monoclonal antibodies are currently being tested in clinical trials and seem promising. This report provides an update of the current preclinical studies and clinical efforts for the development of novel agents in the treatment of WM.

The outcome of haemopoietic stem cell transplantation in the treatment of lymphoplasmacytic lymphoma in the UK: a British Society Bone Marrow Transplantation study

Lymphoplasmacytic lymphoma (LL) is incurable by standard therapy (median survival: 60 months). UK transplant registry data 1984-2003 identified 18 cases of histologically verified LL (median age: 50 years, range: 38-58 years). Nine patients received high dose chemotherapy [plus total body irradiation (TBI) in 1/9] and autologous peripheral blood stem cells (PBSC). Disease status at transplant was complete remission (2), partial remission (5), primary refractory (1) or relapse (1). Transplant related mortality (TRM) at 12 months was 0%. Median follow-up is 44 months with 4 year disease free survival 43% and overall survival 73%. Karnofsky performance status (KPS) is 80-100%. The nine allografted patients (median age: 49 years, range: 39-56 years) were conditioned with standard TBI (2), BEAM (2) or FLU-MEL (5) and received PBSC from HLA-matched sibling (8) or unrelated (1) donors. Disease status at transplant was partial remission (7) or primary refractory (2). TRM at 12 months was 44%. Complications included graft failure (2), grades I-II acute graft versus host disease (aGVHD) (2), grades III-IV aGVHD (3) and chronic GVHD (4). Median follow-up is 32 months with 4 year disease free survival 44% and overall survival 56%. KPS is 70-100%.

Evidence of graft-versus-Waldenstrom's macroglobulinaemia effect after allogeneic stem cell transplantation: a single centre experience

The role of allogeneic stem cell transplantation (SCT) in Waldenstrom's macroglobulinaemia (WM) is not yet clear, as published data on allogeneic SCT in WM are limited. We present a retrospective study of allogeneic SCT in five patients with WM. Median age was 56 years (range 40-60 years). All patients were heavily pretreated. Conditioning therapy with busulphan and cyclophosphamide was used for all patients and all were given cyclosporine and methotrexate for graft-versus-host disease prophylaxis. With a median follow-up of 32 months (range 2-43), all except one are alive and disease free. Progressive, delayed decline in serum IgM levels were noted in all the patients, suggesting an active graft-versus-Waldenstrom's effect. With the limited available data, it appears that allogeneic SCT is a useful treatment option for advanced WM.

Treatment of Waldenstrom’s Macroglobulinemia

Waldenstrom's macroglobulinemia is defined by bone marrow lymphoplasmacytic infiltration and by production of monoclonal IgM. Treatment is employed only to symptomatic patients. Alkylating agents (chlorambucil), nucleoside analogues and rituximab are reasonable choices for primary therapy. Combination therapy either with nucleoside analogues with alkylating agents and/or rituximab or rituximab with chemotherapy such as CHOP or cyclophosphamide are also reasonable frontline treatment options for WM patients. Several factors should be taken into account when choosing the most appropriate primary treatment. These factors include the age of the patient and possible co-morbidities, the presence of cytopenias and especially thrombocytopenia, the presence of symptoms and signs indicative of hyperviscosity, the need for rapid disease control due to severe symptoms, significant splenomegaly or lymphadenopathy, symptomatic peripheral neuropathy and whether the patient is candidate for autologous stem cell transplantation. For patients with refractory or relapsing disease, the use of an alternate first-line agent is reasonable. Outside the setting of a clinical trial, the administration of high-dose therapy should be reserved only for patients refractory to alkylating agents, purine nucleoside and rituximab. For patients who develop resistance to all three classes of agents, alemtuzumab, thalidomide with or without dexamethasone or bortezomib could be tried.

Haematology and neurology

This review aims to update the reader on advances in the understanding of haematological conditions that may arise in neurological practice. Thrombophilia, antiphospholipid antibody syndrome, thrombotic thrombocytopenic purpura, sickle cell and clonal disorders associated with neuropathy are discussed.

Autologous or allogeneic stem cell transplantation in patients with Waldenstrom's macroglobulinemia

The role of hematopoietic stem cell transplantation (SCT) in Waldenstrom's macroglobulinemia (WM) has not been extensively studied. To determine the potential for long-term disease control using SCT in WM, we performed a retrospective review of 36 patients with WM who received autologous (n = 10) or allogeneic (n = 26) SCT and were reported to the Center for International Blood and Marrow Transplant Research between 1986 and 2002. The following outcomes were described: nonrelapse mortality (NRM), relapse, progression-free survival (PFS), and overall survival (OS). Median age at the time of SCT was 51 years (range, 30-76 years), and median time from initial treatment to SCT was 29 months (range, 2-198 months). A total of 78% of the patients had 2 or more previous chemotherapy regimens, and 52% had disease resistant to salvage chemotherapy. In the allogeneic SCT group, 58% of the patients received myeloablative conditioning regimens containing total body irradiation (TBI), and of the allograft recipients, 19% received nonmyeloablative/reduced-intensity conditioning. After a median follow-up of 65 months, 15 of the 36 patients (42%) are alive. Primary disease accounted for 29% of the deaths in the allogeneic SCT group and 25% of the deaths in the autologous SCT group. The relapse rate at 3 years was 29% (95% confidence interval [CI], 14%-48%) in the allogeneic group and 24% (95% CI, 4%-54%) in the autologous group. PFS at 3 years was 31% (95% CI, 14%-50%) in the allogeneic group and 65% (95% CI, 32%-91%) in the autologous group; OS was 46% (95% CI, 27%-65%) in the allogeneic group and 70% (95% CI, 40%-93%) in the autologous group. NRM at 3 years was 40% (95% CI, 23%-59%) in the allogeneic group and 11% (95% CI, 0-36%) in the autologous group. Autologous SCT is a safe and feasible treatment option for patients with WM, especially for those who present with adverse prognostic factors. Allogeneic SCT carries a much higher (40%) risk of NRM and should not be considered outside the context of a clinical trial.

Pentostatin for the Treatment of Indolent Lymphoproliferative Disorders

Purine analogues have been shown to be active in a variety of B- and T-cell malignancies. Among them, pentostatin is also a tight binding inhibitor of adenosine deaminase (ADA), a key enzyme of purine metabolism. ADA is present in all human tissues, with the highest levels in the lymphoid system. Early clinical trials with pentostatin used high doses for acute lymphoblastic leukemias, which were characterized by high levels of ADA. Through the efforts of a few investigators, low-dose regimens that are active and well tolerated for indolent lymphoid malignancies have been developed. Myelosuppressive adverse effects have been shown to be minimal using these schedules. Lymphoplasmacytic lymphoma (LL) is an indolent chronic B-cell lymphoproliferative disorder moderately responsive to alkylating agents. All of the purine analogues have shown activity in LL. However, the advantage of pentostatin over the other agents is the relatively specific toxicity to lymphoid cells and the paucity of myelosuppression as a single agent. No direct comparisons of the agents have been investigated, although pentostatin may be considered to be preferred since it has not been associated with toxicity to myeloid progenitors in colony assays. This is of significance for patients who might benefit from high-dose chemotherapy with autologous stem cell transplantation.

Waldenström's macroglobulinemia

The diagnosis of Waldenström's macroglobulinemia (WM) requires evidence of bone-marrow infiltration by lymphoplasmacytoid lymphoma and detection of serum monoclonal protein of IgM type. The normal counterpart of the WM malignant cell is believed to be a postgerminal-center B cell. The clinical manifestations and laboratory abnormalities associated with WM are related to direct tumor infiltration and to the amount and specific properties of IgM. Asymptomatic patients should be followed without treatment. When treatment is indicated, the three main choices for systemic frontline treatment are chlorambucil, the nucleoside analogues fludarabine or cladribine and the monoclonal antibody rituximab. There is evidence that high-dose therapy with autologous stem-cell transplantation is effective even in patients with advanced and resistant disease. Patient's age, hemoglobin and serum beta2-microglobulin before treatment are important prognostic variables which correlate with survival.

Fludarabine plus cyclophosphamide in Waldenström's macroglobulinemia: results in 49 patients

Fludarabine (FDR) therapy gives a response rate of about 30% in previously treated patients with Waldenström's macroglobulinemia (WM). The combination of FDR and cyclophosphamide (Cy) has been shown to be effective in chronic lymphoproliferative disorders. We administered the combination of FDR (30 mg/m2 i.v. D1-D3) and Cy (300 mg/m2 i.v. D1-D3) to 49 patients. Median age was 64 years. The median hemoglobin, albumin, beta 2 microglobulin and immunoglobulin M (IgM) levels were 9.9 g/100 ml, 39.6 g/l, 3 mg/l and 24.7 g/l, respectively. In all, 14 patients (29%) had not previously been treated. FDR/Cy was administered every 4 weeks for a median of four cycles. In all, 38 patients (77.6%) had partial responses, nine had stable disease and two had progressive disease. After a median of follow-up of 25 months, six patients relapsed and two patients developed large-cell lymphoma. The median time to treatment failure was 27 months. The main toxicity was hematological. In all, 12 patients died, four from progression, one from large-cell lymphoma, three from infection and four from a second malignancy. Two factors negatively influenced overall and event-free survival, age >65 years and IgM <40 g/l. The FDR/Cy combination, therefore, gives a high response rate in WM, even in previously treated patients with factors of poor prognosis.

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.

Diagnosis and management of Waldenstrom's macroglobulinemia

PURPOSE

To review the diagnostic criteria, prognostic factors, response criteria, and treatment options of patients with Waldenstrom's macroglobulinemia (WM).

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

WM should be regarded as a distinct clinicopathologic entity and confined to those patients with lymphoplasmacytoid lymphoma who have demonstrable serum immunoglobulin M monoclonal protein. Treatment decisions should rely on specific clinical and laboratory criteria. Initiation of therapy should not be based on serum monoclonal protein levels per se. The three main choices for systemic primary treatment of symptomatic patients with WM include alkylating agents (chlorambucil), nucleoside analogs (fludarabine and cladribine), and the monoclonal antibody rituximab. There are no data from prospective randomized studies to recommend the use of one first-line agent over another, although consideration of a patient's candidacy for autologous stem-cell transplantation (ASCT) should be taken into account to avoid stem cell-damaging agents. There are preliminary data to suggest that combinations of nucleoside analogs and alkylating agents with or without rituximab may improve response rates at the expense of higher toxicity.

CONCLUSION

WM is a distinct low-grade lymphoproliferative disorder. When therapy is indicated, alkylating agents, nucleoside analogs, and rituximab are reasonable choices. Several factors, including the presence of cytopenias, need for rapid disease control, candidacy for ASCT, age, and comorbidities, should be taken into consideration when choosing the most appropriate primary treatment.

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.

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.