Impact of previous high-dose therapy on outcome after allografting for multiple myeloma

Role of allogeneic transplantation in multiple myeloma in the era of new drugs

High-dose melphalan with autologous stem cell rescue has been regarded as the standard of care for patients with newly diagnosed myeloma up to the age of 65–70 years. The recent development of agents with potent anti-tumor activity such as thalidomide, lenalidomide and bortezomib has further improved overall survival and response rates. However, relapse is a continuous risk.

Allografting is a potentially curative treatment for a subset of multiple myeloma patients for its well documented graft-vs-myeloma effects. However, its role has been hotly debated. Even though molecular remissions have been reported up to 50% after high-dose myeloablative conditionings, their applications, given the high toxicity, have been for long limited to younger relapsed/refractory patients. These limitations have greatly been reduced through the introduction of non-myeloablative/reduced-intensity conditionings.

The introduction of new drugs, characterised by low risks of early mortality, indeed requires to define role and timing of an allograft to capture the subset of patients who may most benefit from graft-vs-myeloma effects.

Ultimately, new drugs should not be viewed as mutually exclusive with an allograft. They may be employed to achieve profound cytoreduction before and enhance graft-versus-myeloma effects as consolidation/maintenance therapy after an allograft. However, this combination should be explored only in well-designed clinical trials.

A fludarabine, thiotepa reduced toxicity conditioning regimen designed specifically for allogeneic second haematopoietic cell transplantation after failure of previous autologous or allogeneic transplantation

We present a phase II study of fludarabine 5 x 30 mg/m(2), thiotepa 3 x 5 mg/kg as preparative regimen specifically for allogeneic second haematopoietic stem cell transplantation (HCT) after failure of previous HCT. Forty-nine patients (median age 52 years, range 27-68) received an allogeneic second HCT after failed autologous (n=29) or allogeneic (n=20) HCT. Diagnoses were AML (n=18), ALL (n=3), multiple myeloma (n=11), lymphoma (n=16) and CML (n=1). GVHD prophylaxis consisted of CYA and mainly low dose alemtuzumab (40 mg). The median follow-up for patients alive is 528 days (range 217-1344). In 43 of 49 (88%) evaluable patients response rates were CR=19, PR=14 and SD=10 at one month. At one year, the probability (95% confidence interval) of relapse is 55.1 (38.2-72)% and the nonrelapse mortality (NRM) is 29 (14.2-44.4)%. Estimated survival at one year is 42.6 (28.7-56.6)% and event free survival is 38.1 (24.4-51.8)%. Survival was significantly better for patients experiencing relapse beyond one year, than for patients relapsing within one year from first transplantation (51.2 (33.5-68.9)% vs 27 (7-48.5)%; P=0.013). We conclude that this regimen is feasible and well tolerated for allogeneic second HCT.

The evolving background for high-dose treatment for myeloma

In the constantly evolving field of myeloma, this special issue is slanted towards how the newer targeted treatments fit in with various transplantation strategies. High-dose treatment for myeloma with autologous stem cell transplantation started 25 years ago, with the consequence of producing complete remissions and a doubling of survival. Since then, its role has been refined and it has been accepted as standard treatment. The current challenge is to optimize its use into a background of the development, availability and regulatory approval of newer targeted therapies such as Thalidomide, Revlimid (Lenalidomide) and Velcade (Bortezomib). This special issue addresses these problems, and gives particular emphasis on the attainment of very long-term survival, with normal quality of life for patients with myeloma who do not necessarily need to be cured of their molecular disease, that is, they are 'operationally cured.' It is hoped that the reader will find the information in this issue useful in the day-to-day management of patients and we hope that this will also inspire new research directions designed to improve the outcome of patients with myeloma.

Myeloablative allogeneic stem cell transplantation for advanced stage multiple myeloma: very long-term follow up of a single center experience

We aimed to review the long-term outcome of myeloablative allogeneic stem cell transplantation (SCT) performed for multiple myeloma (MM) at our institution. Records of all patients who received standard myeloablative allogeneic SCT for MM were retrospectively reviewed. Overall survival (OS), progression-free survival (PFS), and event-free survival (EFS) were calculated using the Kaplan-Meier method. In total 37 transplants had been performed. Median follow up post-SCT was 108 months (range: 33-148). The majority of patients suffered advanced stage disease and/or had received multiple prior therapies prior to SCT. Transplant-related mortality (TRM) at 100 days was 32%. Grades 2-4 acute graft-vs.-host disease (GVHD) occurred in 18 patients (49%), and extensive stage chronic GVHD in seven (28%) of 25 patients surviving greater than day 100. Median OS, PFS, and EFS were 28 months, 66 months and 13 months, respectively, with 5 year OS, PFS, and EFS 40%, 54% and 24%. Our results suggest that allogeneic SCT, even when performed in advanced stage, heavily pretreated MM, still results in long-term EFS in a significant minority of patients. Efforts should continue on alternative allogeneic SCT approaches to reduce the high early TRM rate associated with myeloablative conditioning.

Variable incidence of cyclosporine and FK-506 neurotoxicity in hematopoeitic malignancies and marrow conditions after allogeneic bone marrow transplantation

INTRODUCTION

This study examines whether malignant disease under treatment influences the incidence of cyclosporine or FK-506 neurotoxicity after myeloablative conditioning and allogeneic bone marrow transplantation (allo-BMT).

METHODS

Review of 290 patients who received myeloablative conditioning prior to allo-BMT and cyclosporine/FK-506 identified 21 (7.2%) patients with neurotoxicity confirmed by computed tomography or magnetic resonance. Underlying malignancy necessitating allo-BMT included leukemias (67%), lymphoma (10%), myelodysplastic syndrome (10%), and multiple myeloma (MM). Frequency of neurotoxicity by disease was compared.

RESULTS

The highest incidence of neurotoxicity was present with MM (25%), whereas the lowest incidence was present with lymphoma (2.7%). Other diseases demonstrated intermediate incidence, including acute leukemias (10%), myelodysplastic syndrome (6.4%), and chronic myelogenous leukemia (4.9%).

CONCLUSION

Cyclosporine/FK-506 neurotoxicity varied according to the underlying malignancy. The variable susceptibility to the development of neurotoxicity in this population may depend on the interaction of host vasculature with disease specific factors. Understanding the cause of neurotoxicity could improve survival after allo-BMT.

Effect of age and previous autologous transplantation on nonrelapse mortality and survival in patients treated with reduced-intensity conditioning and allografting for advanced hematologic malignancies

PURPOSE

Older age and a previously failed autologous stem-cell transplantation (SCT) are poor prognostic factors for patients receiving myeloablative conditioning and allogeneic SCT. Reduced-intensity conditioning (RIC) regimens achieved a significant reduction of treatment-related mortality, but the influence of previously described risk factors on the outcome of this novel transplantation strategy have not been fully analyzed yet.

PATIENTS AND METHODS

One hundred fifty patients with advanced hematologic malignancies received a RIC regimen containing thiotepa (10 mg/kg), fludarabine (60 mg/m2), and cyclophosphamide (60 mg/kg), followed by an allogeneic transplantation from an HLA-identical sibling donor. Patients were divided into two cohorts according to age; 90 patients were younger than 55 years, and 60 patients were 55 years old or older. The other pretransplantation characteristics were fairly balanced.

RESULTS

Actuarial 5-year nonrelapse mortality (NRM) rate was not statistically different between the groups (13% in the younger group and 19% in the older group). By univariate and multivariate analysis, NRM was significantly higher in older patients who previously experienced failure with an autograft. The occurrence of grade 3 to 4 acute graft-versus-host disease (GVHD) or extensive chronic GVHD was associated with a higher NRM in both age cohorts. Overall survival (OS) was not statistically different between the younger (66%) and older groups (61%). By multivariate analysis, refractory disease was associated with a worse OS irrespective of age group.

CONCLUSION

RIC transplantations show a rather low NRM, and age > or = 55 years per se cannot be considered a risk factor anymore. The timing of transplantation and novel strategies for the prevention of severe GVHD could further improve patient outcome.

Prognostic role of minimal residual disease in multiple myeloma patients after non-myeloablative allogeneic transplantation

This study evaluates the prognostic value of molecular monitoring of minimal residual disease (MRD) in 20 patients with multiple myeloma (MM) following autologous (peripheral blood stem cell transplantation, PBSCT) and non-myeloablative allogeneic (NMT) transplant. All patients completed their program, with a treatment-related mortality (TRM) of 20% and a 2-year progression-free survival (PFS) of 51%. After PBSCT, only 3 patients (15%) achieved PCR-negativity, versus 12 (60%) after NMT. The eradication of MRD had a favorable impact on 2-year OS. In fact, 76% of patients with no detectable MRD was still alive versus 34% of persistently IgH-positive cases (p=0.03). PCR status did not correlate with chimerism percentage: Seventy-five percent of patients achieved full donor chimerism, which was more frequently observed in cases presenting cGHVD (p=0.01). These data sustain the relevant role of molecular monitoring in MM patients undergoing NMT. MRD monitoring would assist physicians in making additional therapeutic decisions to better control this hematological malignancy.

Outcome of unrelated transplants in patients with multiple myeloma

The outcome of patients with multiple myeloma treated with standard therapy is disappointing, with a historical median survival of 3 years. Although high-dose therapy with autologous stem cell transplant has improved treatment outcomes, cure is unlikely. Allogeneic transplant provides a tumor-free graft and a graft-versus-myeloma effect. However, only a minority of patients has a compatible sibling donor. Unrelated hematopoietic stem cell transplant is another option. We analyzed the outcome of patients who received an unrelated bone marrow transplant facilitated by the National Marrow Donor Program (NMDP). Between 1989 and 2000, 71 patients received a myeloablative unrelated transplant for multiple myeloma; 70 patients consented for this analysis. The median recipient age was 44 years. A total of 31% of patients had received a prior autologous transplant. In all, 91% of patients engrafted. The 3-year cumulative incidence estimate of relapse was 34+/-10%. The incidence of Grade II-IV GVHD was 47%. The Kaplan-Meier estimate for overall survival at 5 years was 9+/-7%. The 100-day treatment-related mortality was 42%. In multivariate analysis, only a male donor was a significant predictor for survival. Better strategies are needed to treat patients with multiple myeloma, perhaps by using less-toxic, nonmyeloablative conditioning regimens.

Multiple myeloma

Multiple myeloma is a malignant disease of plasma cells that manifests as one or more of lytic bone lesions, monoclonal protein in the blood or urine, and disease in the bone marrow. Treatment for myeloma has changed beyond recognition in the past decade, and now includes state of the art supportive treatment and infusional chemotherapy courses, followed for younger patients by high-dose melphalan and an autologous transplant. Patients younger than 70 years can now expect a doubling of median survival to 5 years, a 20% chance of surviving longer than 10 years, and a 50% chance of attaining complete morphological and biochemical remission. Bisphosphonate control of bone disease is essential. Exploitation of the understanding of the biology of myeloma has led to the development of biological treatments, such as thalidomide, CC-5013, and bortezomib, which target the myeloma cell and the bone-marrow microenvironment, which plays a crucial part in the disease's pathogenesis. These treatments will hold the key to future success.

High rate of remission and low rate of disease recurrence in patients with multiple myeloma allografted with PBSC from their HLA-identical sibling donors

A total of 30 multiple myeloma patients (M=23, F=7; age 31-55 years, median 48) were allografted with peripheral blood stem cells (PBSC) from HLA-identical siblings. Time to transplantation was 3-107 months (median 8). Prior chemotherapy lines varied from 1 to 6 (median 1). Four patients were in complete remission (CR), 11 in partial remission (PR), 13 were considered to be nonresponders, and two had progressive disease. Most were conditioned with busulfan-melphalan. PBSC were collected by apheresis after G-CSF or sequential GM-CSF and G-CSF. The patients were grafted with 4.4-24.1 x 10(6)/kg CD34+ (median 7.9) and 0.9-7.9 x 10(8)/kg CD3+ cells (median 2.3). GVHD prophylaxis was methotrexate-cyclosporine. Engraftment was complete and rapid. Grades II-IV acute GVHD (aGVHD) developed in 16 (53%), but was grade III-IV only in five (17%); chronic GVHD (cGVHD) developed in 17 out of the 24 evaluable patients (71%). A total of 18 patients (71%) attained CR after transplantation. TRM was 30% overall, 16% at 100 days. There was only one relapse. Overall survival and event-free survival at 73 months were 60% and 67%, respectively. PCR negativity for IgH-gene rearrangement occurred in all persistently CR patients studied. PBSC allograft can induce long remissions, because of profound suppression of the neoplastic clone that is probably linked to the antitumor effect of cGVHD.

Follow-up of patients with progressive multiple myeloma undergoing allografts after reduced-intensity conditioning

Allogeneic stem cell transplantation (allo-SCT) after reduced-intensity conditioning was evaluated in 22 patients (median age 53, range 36-66 years) with multiple myeloma with progression after an autologous SCT. Seven patients received a transplant from a human leucocyte antigen (HLA)-identical sibling and 15 patients (68%) from an unrelated donor [including 3/22 (14%) from a HLA-mismatched unrelated donor]. Graft-versus-host disease (GVHD) prophylaxis consisted of serotherapy with antithymocyte globulin (ATG) and cyclosporine (CSA) (n = 12) or CSA plus mycophenolate mofetil (n = 10). Despite of heavy pretreatment, the transplant-related mortality (TRM) for all grafted patients was acceptable at 5/22 patients (23%). Seven of 21 patients (33%) that were evaluated developed grade II GVHD and one (5%) patient developed grade III/IV acute GVHD. Seven patients developed chronic GVHD (cGVHD), but only one was extensive. Eleven patients died of progressive disease within a median of 7 months (2-19 months) post transplant. Thirteen of all 22 patients (59%) achieved a partial or complete remission with six of these 13 patients (46%) remaining event free at a median of 24 months (range 8-36 months) post allografting. Estimated 2 year overall and event-free survival was, respectively, 25.5% and 22.0% for the whole patient group, and 62.5% and 57.1% for patients with chemosensitive disease. Chemorefractory disease prior to allogeneic stem cell transplantation (P = 0.0182) and absence of cGVHD (P = 0.069) were associated with shorter event-free survival. Thus long-term disease control can be achieved, but is restricted to patients responding to prior salvage chemotherapy.

The role of cytotoxic therapy with hematopoietic stem cell transplantation in the therapy of multiple myeloma: an evidence-based review

Evidence supporting the role of hematopoietic stem cell transplantation (SCT) in the therapy of multiple myeloma (MM) is presented and critically evaluated in this systematic evidence-based review. Specific criteria were used for searching the published medical literature and for grading the quality of the evidence, the strength of the evidence, and the strength of the treatment recommendations. Treatment recommendations based on the evidence presented in the review were made unanimously by a panel of MM experts. Recommendations for SCT as an effective therapy for MM include the following: SCT is preferred to standard chemotherapy as de novo therapy; SCT is preferred as de novo rather than salvage therapy; autologous peripheral blood stem cell transplantation (PBSCT) is preferred to bone marrow transplantation (BMT); and melphalan is preferred to melphalan plus total body irradiation as the conditioning regimen for autologous SCT. Recommendations that SCT is not effective include the following: current purging techniques of bone marrow. Recommendations of equivalence include the following: PBSCT using CD34+ selected or unselected stem cells. No recommendation is made for indications or transplantation techniques that have not been adequately studied, including the following: SCT versus standard chemotherapy as salvage therapy, tandem autologous SCT, autologous or allogeneic SCT as a high-dose sequential regimen, allogeneic BMT versus PBSCT, a preferred allogeneic myeloablative or non-myeloablative conditioning regimen, and maintenance therapy post-autologous SCT with interferon alpha post-SCT. The priority area of needed future research is maintenance therapy posttransplantation with nothing versus interferon alpha versus other agents such as corticosteroids or thalidomide or its derivatives.

Role of nonmyeloablative allogeneic stem-cell transplantation after failure of autologous transplantation in patients with lymphoproliferative malignancies

PURPOSE

Conventional allogeneic stem-cell transplantation (SCT) after a prior failed autograft is associated with a transplant-related mortality rate of 50% to 80%. The aim of the current study was to evaluate the safety and efficacy of sibling, HLA-matched, nonmyeloablative allogeneic SCT with donor lymphocyte infusion (DLI) in patients with lymphoid malignancy after failure of autologous SCT.

PATIENTS AND METHODS

A total of 38 patients with refractory, progressive, or relapsed disease after autologous SCT were entered onto this study. The conditioning regimen consisted of the humanized monoclonal antibody CAMPATH-1H, fludarabine, and melphalan. Fifteen of 35 assessable patients received DLI after SCT.

RESULTS

Sustained neutrophil engraftment was achieved in 37 recipients, and platelet engraftment was achieved in 35 patients. The estimated transplant-related mortality was 7.9% at day 100 and 20% at 14 months, the median duration of follow-up. Eight patients experienced grade I/II acute graft-versus-host disease (GVHD) after transplantation, but no grade III/IV GVHD was observed in this setting. However, grade III/IV GVHD occurred in seven patients who received DLI. The actuarial overall survival at 14 months was 53%, with a progression-free survival of 50%. DLI produced a further response in three of 15 recipients.

CONCLUSION

Nonmyeloablative allogeneic SCT after CAMPATH-1H-containing conditioning is a relatively safe option compared with conventional allogeneic transplantation for patients who have failed previous autologous SCT. The low incidence of early GVHD enabled the subsequent administration of DLI to improve further clinical responses in this poor-risk group of lymphoma and myeloma patients.

Low transplant-related mortality after second allogeneic peripheral blood stem cell transplant with reduced-intensity conditioning in adult patients who have failed a prior autologous transplant

Standard allogeneic stem cell transplantation (SCT) has been associated with a high transplant-related mortality (TRM) in patients who have failed a prior autologous SCT (ASCT). Reduced-intensity conditioning (RIC) regimens may reduce the toxicities and TRM of traditional myeloablative transplants. We report 46 adults who received a RIC peripheral blood SCT from an HLA-identical sibling in two multicenter prospective studies. The median interval between ASCT and allograft was 16 months, and the patients were allografted due to disease progression (n = 43) and/or secondary myelodysplasia (n = 4). Conditioning regimens consisted of fludarabine plus melphalan (n = 41) or busulphan (n = 5). The 100-day incidence of grade II-IV acute graft-versus-host disease (GVHD) was 42% (24% grade III-IV), and 10/30 evaluable patients developed chronic extensive GVHD. Early complete donor chimerism in bone marrow and peripheral blood was observed in 35/42 (83%) patients, and 16 evaluable patients had complete chimerism 1 year post transplant. With a median follow-up of 358 days (450 in 29 survivors), the 1-year incidence of TRM was 24%, and the 1-year overall (OS) and progression-free survival were 63% and 57%, respectively. Patients who had chemorefractory/ progressive disease, a low performance status or received GVHD prophylaxis with cyclosporine A alone (n = 32) had a 1-year TRM of 35% and an OS of 46%, while patients who had none of these characteristics (n = 32) had a 1-year TRM of 35% and an OS of 46% while patients who had none of these characteristics (n = 14) had a TRM of 0% and an OS of 100%. Our results suggest that adult patients who fail a prior ASCT can be salvaged with a RIC allogeneic PBSCT with a low risk of TRM, although patient selection has a profound influence on early outcome.

Continuous complete clinical and molecular remission in two patients with refractory lymphoid malignancies after autografting followed by allogeneic stem cell transplantation with reduced intensity conditioning

We present a 60-year-old patient with primary refractory non-Hodgkin's lymphoma and a 58-year-old patient with multiple myeloma with relapse after first autologous stem cell transplantation (ASCT), who underwent ASCT followed by allogeneic stem cell transplantation (alloSCT) with reduced intensity conditioning consisting of fludarabine and a single dose of total body irradiation. For graft-versus-host disease prophylaxis cyclosporine and mycophenolate mofetyl were given. Complete donor chimaerism was observed on d 28 after SCT. Both patients achieved sustained complete haematological and molecular remission of the immunoglobulin kappa light chain (Igkappa) rearrangement and are alive and well 17 and 16 months after SCT respectively.

International myeloma grand round

On the 14th June 2001, The Royal Marsden Hospital, London, hosted an unusual event, an international grand round, aimed at exploring a new concept in the treatment of multiple myeloma--operational cure. The speakers were Jean-Luc Harousseau (France), Gregory Mundy (USA), Brian Durie (USA) and Ray Powles (UK). Case histories were presented by Bhawna Sirohi (UK). The 80 invited guests included oncologists, radiotherapists, histopathologists, representatives of the International Myeloma Foundation, members of the press, and several myeloma patients, including the two whose case histories are presented below.

Some early phase II trials in previously untreated multiple myeloma: The Royal Marsden experience

Multiple myeloma is at a stage today where acute leukemia was in the 1960s and 1970s when the aim was to attain complete remission (CR), which would translate into prolonged overall survival (OS) and a cure. The Royal Marsden group was the first to establish a dose-response effect for melphalan leading to CR in patients with myeloma. Since then, different strategies have been developed to improve the results of high-dose therapy, including alternating conditioning regimens, peripheral blood stem cells (PBSC) as a source of stem cells, purging techniques to decrease graft contamination by the myeloma cell, increased dose intensity by means of tandem transplants, and finally, allogeneic matched or unmatched stem cell transplantation. Components of treatment offered at Royal Marsden since 1980 are upfront high-dose melphalan (HDM) 140 mg/m(2), induction infusional chemotherapy followed by consolidation with HDM with autotransplantation, and maintenance with interferon-alpha2b (IFN) (collectively termed sequential therapy). Each of these components has shown benefits in selected studies and together they have dramatically improved the outlook for patients with myeloma.

Comparison of new patients with Bence-Jones, IgG and IgA myeloma receiving sequential therapy: the need to regard these immunologic subtypes as separate disease entities with specific prognostic criteria

Of the 61 newly diagnosed patients with Bence-Jones (BJ) myeloma presenting to our centre between May 1986 and December 1997, 53 received sequential therapy (ST) comprising infusional chemotherapy (IC) followed by high-dose therapy and autotransplantation with interferon-alpha2b maintenance. The outcome was compared with 153 IgG and 39 IgA similarly treated myeloma patients. Response to IC and high-dose was comparable between the three subtypes but a significantly higher proportion of patients with BJ myeloma failed to receive high-dose compared to IgG (P = 0.003) and IgA (P = 0.04) myeloma. Median overall survival (OS) of patients with BJ myeloma (2.8 years) and event-free survival (EFS, 1.2 years) was significantly shorter than for patients with IgG myeloma (4.5 years, P = 0.03 and 2.1 years, P = 0.03, respectively). However, among those patients who achieved complete remission there was no difference in OS and EFS between IgG and BJ myeloma. In distinction to IgG myeloma where age and beta2M were significant, Cox analysis on presentation features identified performance status and urine total protein as having significant impact on OS. We conclude that achieving CR is an important treatment aim in patients with BJ myeloma, conferring a similar outlook on survival as in patients with the IgG subtype, and there is a need to consider different subtype-specific staging systems when evaluating the results of published or ongoing therapeutic trials.

Hypercalcemia after High-Dose Chemoradiotherapy for Refractory Multiple Myeloma; Subject Heading

A 43-year-old man with refractory myeloma underwent allogeneic bone marrow transplantation from his HLA-matched sibling. He was conditioned with TBI (12 Gy) followed by melphalan (140 mg/m(2) ). Immediately after conditioning was initiated, he began complaining of severe lumbago, and the level of serum calcium rose from 2.25 to 3.34 mmol / l. However, the biochemical markers for tumor-lysis syndrome such as potassium, uric acid, and lactic dehydrogenase remained unchanged. Hydration with saline and pamidronate were started, but he developed acute renal failure requiring hemodialysis for 3 weeks. His plasma parathyroid hormonerelated protein (PTHrP)-NH2-terminal (3.9 pmol/l) and serum PTHrP-C-terminal (125.0 pmol / l) levels markedly increased immediately after conditioning. These results suggested that the increased release of PTHrP from myeloma cells, which resulted from destruction of myeloma cells by conditioning, was the primary contributes to the occurrence of hypercalcemia. We should be aware of the occurrence of hypercalcemia when high-dose therapy is to be given to patients with refractory myeloma.

Immunotherapy by non-myeloablative allogeneic stem cell transplantation in multiple myeloma: results of a pilot study as salvage therapy after autologous transplantation

Non-myeloablative allogeneic stem cell transplantation has been reported to induce sustained complete remission even in advanced diseases (acute leukemia, lymphomas). The tolerance of this procedure allows treatment of poor candidates to conventional allogeneic transplantation with persisting or relapsing myeloma patients. Twelve patients previously treated with at least VAD regimen and autologous transplantation were included. All patients had a serum beta2 microglobuline >3 mg/l at diagnosis. The conditioning regimen consisted of fludarabine 25 mg/m/day x 5, antithymoglobulin 2.5 mg/kg/day x 5, busulphan 2 mg/kg/day x 2; the transplant was peripheral stem cells (except one) from an HLA-matched sibling and was followed by cyclosporin for 45 to 90 days. This treatment results in a well-tolerated procedure (no mucositis, duration of aplasia <7 days). A dramatic graft anti-myeloma effect is documented even in progressive disease (11/12 PR + CR, 4/12 CR). However, five patients underwent CMV disease, one died of CMV encephalitis (UPN 3) and delayed severe GVHD occurred in four patients. Our data suggest that a better survival could be achieved when patients are transplanted with a controlled disease. In high risk patients, we now propose a non-myeloablative transplantation in addition to the conventional and intensive chemotherapy as first-line of treatment.

Allogeneic stem cell transplantation reduces disease progression compared to autologous transplantation in patients with multiple myeloma

This study compares the probability of disease progression, progression-free survival, and overall survival between patients undergoing an allogeneic or autologous transplant for multiple myeloma using an identical preparative regimen. Patients received a preparative regimen of TBI, busulfan, and cyclophosphamide followed by an allogeneic or autologous transplant. In the allogeneic group (n = 21), six patients received bone marrow and 15 received G-CSF mobilized PBSC; all autologous patients (n = 35) received PBSC mobilized with cyclophosphamide and G-CSF. Allogeneic donors were HLA-identical (n = 20) or one-antigen mismatched (n = 1) siblings. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus (n = 10), tacrolimus/methotrexate (n = 6), cyclosporine/methotrexate (n = 4), or cyclosporine (n = 1). The groups were evenly matched for gender, pretransplant therapy, disease status at time of transplant, myeloma subtype, and time from diagnosis to transplant. The median age was significantly lower in the allogeneic group (48 vs 55 years, P < 0.01). In the allogeneic group the probabilities of developing acute GVHD grade II-IV and chronic GVHD were 55% and 82%, respectively. The Kaplan-Meier probability of disease progression was significantly lower in the allogeneic group (11% vs 64%, P < 0.001) compared to the autologous group. Although progression-free (60% vs 30%, P = 0.19) and overall survival at 2 years (60% vs 42%, P = 0.39) favored the allogeneic group, this did not reach statistical significance. Within the allogeneic transplant group, patients age 50 years or under had a 3-year overall survival significantly higher when compared to older patients (79% vs 29%, P = 0.03). Using identical preparative regimens, allogeneic transplantation reduced disease progression compared to autologous transplantation for myeloma. This suggests that allogeneic transplantation induces a graft-versus-myeloma (GVM) effect.

Allogeneic haemopoietic stem cell transplantation for multiple myeloma or plasma cell leukaemia using fractionated total body radiation and high-dose melphalan conditioning

We have evaluated the outcome of allogeneic haemopoietic stem cell transplantation for multiple myeloma using a conditioning regimen comprising fractionated total body irradiation and high-dose melphalan (110 mg/m2). The study comprised 25 patients (median age 49 years) who had been transplanted by either bone marrow (n = 13) or G-CSF mobilized peripheral blood stem cells (n = 12). Overall transplant-related mortality was 30% but was lower for patients < 50 years of age at transplant (21%). The main cause of treatment-related mortality was viral infection. Of the 19 patients evaluable post-transplant, 17 have so far achieved complete remissions. Currently, with a median follow-up of 3.4 years, 18 out of 25 patients are alive, of whom 15 are in continuing complete remission (CR) and 2 in second remission after suffering localized relapses, which were treated with radiotherapy and donor leucocyte infusions. Patients transplanted after 1 line of previous therapy, < 50 years of age and receiving peripheral blood stem cells (PBSC) rather than bone marrow (BM) had a superior outcome, although there was no statistically significant factor. We conclude that allogeneic transplantation should be considered as a potentially curative option for younger patients with myeloma and that the regimen using fractionated total body irradiation and melphalan has a high CR rate and a relatively low risk of treatment-related mortality, particularly in younger patients.

Non-myeloablative allogeneic transplantation ('microallograft') for refractory myeloma after two preceding autografts: feasibility and efficacy in a patient with active aspergillosis

A 59-year-old man with a 4-year history of light chain myeloma relapsing after two preceding autografts and salvage therapy with thalidomide underwent a peripheral blood stem cell (PBSC) transplant from his HLA-identical sister after conditioning with 100 mg/m2 melphalan. Graft-versus-host disease (GVHD) prophylaxis comprised cyclosporine. Despite pulmonary infiltrates and sinusitis at the time of the allograft, it was decided to proceed with the transplant because the myeloma was refractory and rapidly progressive. Sputum cultures obtained 2 days before the allograft grew Aspergillus fumigatus 2 days post transplant. A fumigatus grew repeatedly on specimens obtained post transplant. Prompt hematologic recovery was seen with full donor-type chimerism. The fungal infection subsided gradually on a combination of amphotericin B lipid complex and itraconazole. A second aliquot of donor PBSC was infused electively on day +42 to induce graft-versus-myeloma. Complete remission of the myeloma was achieved by 75 days post transplant. No acute GVHD was seen. No chronic GVHD was seen at 16 weeks when he received the third PBSC infusion. He is currently alive and well in remission 9 months post transplant. This case demonstrates the safety and potential usefulness of allogeneic PBSC transplantation with reduced-intensity conditioning in patients with markedly compromised performance status.

Multiple myeloma

Multiple myeloma (MM) is an incurable plasma cell dyscrasia that remains fatal. Despite efforts over the past 3 to 4 decades, the median survival of patients with MM does not exceed 3 to 4 years. Although patients receiving combination chemotherapy have higher response rates compared with those receiving oral melphalan and prednisolone, they have no survival advantage. High-dose chemotherapy followed by autologous stem cell transplantation has documented benefit over conventional treatment and is currently the accepted mode of treatment for symptomatic MM. Allogeneic transplantation is associated with high complete remission rates, but at the cost of high therapy-related mortality. Maintenance treatment with interferon-alpha shows benefit, albeit in a small fraction of MM patients. The use of bisphosphonates in patients with MM has clearly demonstrated benefit and reduced morbidity associated with bone disease. All of these measures have improved remission rates and survival, but all patients with MM ultimately relapse and succumb to their disease. Novel therapeutic strategies are therefore required to improve outcome of MM patients. The responses noted to thalidomide in MM are encouraging. Immune-based strategies, including both adoptive immunotherapy and vaccinations, are currently being investigated in the preclinical and clinical setting, with the goal of enhancing autologous and allogeneic anti-MM immunity for therapeutic applications.