Graft-versus-myeloma effect following antithymocyte globulin-based reduced intensity conditioning allogeneic stem cell transplantation

Allogeneic Transplantation in Multiple Myeloma-Does It Still Have a Place?

Novel drugs have improved survival for patients with multiple myeloma in recent years. However, the disease is still fatal. Allogeneic stem cell transplantation (Allo) has proven to cure some patients with the disease, but its role is controversial due to relatively high transplant-related toxicity and mortality (nonrelapse mortality, NRM). Using nonmyeloablative reduced-intensity conditioning (RIC), both toxicity and NRM can be reduced, and RICAllo is, therefore, an option for subgroups of patients. Upfront tandem autologous/RICAllo (Auto/RICAllo) was shown to be superior to single Auto or tandem Auto/Auto in both progression-free (PFS) and overall survival (OS) in two prospective studies with long-term follow-up, while three similarly designed studies did not detect a difference. A recent update of pooled patient data from four of these studies showed significantly superior PFS and OS with Auto/RICAllo. Importantly, none of these studies showed inferior results with Auto/RICAllo in patients less than 70 years of age. Auto/RICAllo appears to overcome some poor risk cytogenetic markers. Encouraging results have also been seen in treatment of relapsed patients. Combining Allo with new proteasome inhibitors and immunomodulatory drugs may further improve results. Other encouraging new cell therapies such as with CAR T-cells, NK- and CAR NK-cells may well have a place in combination with RICAllo. Such studies are warranted.

Comparison of outcomes after human leukocyte antigen-matched and haploidentical hematopoietic stem-cell transplantation for multiple myeloma

Background:

Allogeneic stem-cell transplantation (SCT) is a well-established immunotherapeutic strategy for multiple myeloma (MM) with a potent and often sustained graft-vs.-myeloma effect. This multicenter investigation aimed to analyze the complications and survival of haploidentical SCT in patients with MM, and compare the main outcomes with matched-related donors (MRDs).

Methods:

Haploidentical and MRD SCT was identified from a cohort of 97 patients with MM who received a myeloablative transplantation in 13 hospitals from May 2001 to December 2017. A matched-pair analysis was designed. For each haplo recipient, the recipients were randomly selected from the MRD group and were matched according to the following criteria: year of the hematopoietic SCT (±2 years), disease status at transplantation, and the length of follow-up.

Results:

Seventy cases received MRD and 27 received haploidentical transplantation. The two groups showed no significant differences regarding age, gender, cytogenetic risk, and diagnostic stage. The cumulative incidences of non-relapse mortality (NRM) at 1 and 3 years based on donor type were 20.5% (95% confidence interval [CI], 10.90–30.10%) and 24.2% (95% CI, 13.81–34.59%) for the MRD group and 16.80% (95% CI, 1.71–31.89%) and 28.70% (95% CI, 8.71–48.69%) for the haplo group, respectively. Cumulative incidence of NRM did not differ significantly between the two groups (χ² = 0.031, P = 0.861). The cumulative incidences of progression-free survival (PFS) and 1 year and 3 years by type of donors were 59.8% (95% CI, 48.24–71.36%) and 45.4% (95% CI, 33.44–57.36%), and 65.6% (95% CI, 47.18–84.02%) and 26.8% (95% CI, 7.59–46. 01%) for MRD and haploidentical donor, respectively. Cumulative incidence of PFS did not differ significantly between the two groups (χ² = 0.182, P = 0.670). In multivariate analyses, no statistically significant differences were observed between haploidentical and MRD for relapse, NRM, PFS, and overall survival. There were no statistically differences on main outcomes after haploidentical and MRD.

Conclusion:

Haploidentical SCT could be performed safely and feasibly for patients with MM in need.

Outcomes of unrelated cord blood transplantation in patients with multiple myeloma: a survey on behalf of Eurocord, the Cord Blood Committee of Cellular Therapy and Immunobiology Working Party, and the Chronic Leukemia Working Party of the EBMT

Although allogeneic stem cell transplantation is not a standard therapy for multiple myeloma, some patients can benefit from this intense therapy. There are few reports on outcomes after umbilical cord blood transplantation in multiple myeloma, and investigation of this procedure is warranted. We retrospectively analyzed 95 patients, 85 with multiple myeloma and 10 with plasma cell leukemia, receiving single or double umbilical cord blood transplantation from 2001 to 2013. Median follow up was 41 months. The majority of patients received a reduced intensity conditioning. The cumulative incidence of neutrophil engraftment was 97%±3% at 60 days, and that of 100-day acute graft-versus-host disease grade II-IV was 41%±5%. Chronic graft-versus-host disease at two years was 22%±4%. Relapse and non-relapse mortality was 47%±5% and 29%±5% at three years, respectively. Three-year progression-free survival and overall survival were 24%±5% and 40%±5%, respectively. Anti-thymocyte globulin was associated with decreased incidence of acute graft-versus-host disease, higher non-relapse mortality, decreased overall and progression-free survival. Patients with high cytogenetic risk had higher relapse, and worse overall and progression-free survival. In conclusion, umbilical cord blood transplantation is feasible for multiple myeloma patients.

The role of tandem stem cell transplantation for multiple myeloma patients

INTRODUCTION

Autologous Stem Cell Transplantation (ASCT) represents the standard treatment in eligible "de-novo" multiple myeloma (MM) patients.

AREAS COVERED

ASCT may be single or tandem, and a single ASCT can be followed by an allogeneic (Allo)-SCT. A systematic review has been conducted to examine the current evidence for the efficacy of using a tandem transplant strategy in MM.

EXPERT OPINION

A tandem ASCT approach should be considered for all patients, although the benefit from the second ASCT in patients who are in complete remission or experience a very good partial response should be answered in a clinical trial. Recent results with the new induction regimens indicate that there is a role for tandem ASCT in the presence of adverse cytogenetic abnormalities. Planned AlloSCT after ASCT has not been found to be superior in the majority of studies and is not recommended outside of a clinical trial. However, single or tandem ASCT are both appropriate options and participation in prospective clinical trials should be encouraged to resolve the debate in the era of novel agents for MM.

Pushing the envelope-nonmyeloablative and reduced intensity preparative regimens for allogeneic hematopoietic transplantation

Allogeneic hematopoietic cell transplantation (HCT) was originally developed to allow delivery of myeloablative doses of chemotherapy and radiotherapy. With better understanding of disease pathophysiology, the graft vs malignancy (GVM) effect of allogeneic hematopoietic transplantation and toxicities associated with myeloablative conditioning (MAC) regimens, the focus shifted to developing less toxic conditioning regimens to reduce treatment-related morbidity without compromising survival. Although HCT with MAC is preferred to reduced intensity conditioning (RIC) for most patients ⩽60 years with AML/myelodysplastic syndrome and ALL, RIC and nonmyeloablative (NMA) regimens allow HCT for many otherwise ineligible patients. Reduced intensity preparative regimens have produced high rates of PFS for diagnoses, which are highly sensitive to GVM. Relapse of the malignancy is the major cause of treatment failure with RIC/NMA HCT. Incorporation of novel agents like bortezomib or lenalidomide, addition of cellular immunotherapy and use of targeted radiation therapies could further improve outcome. In this review, we discuss commonly used RIC/NMA regimens and promising novel regimens.

Multiple myeloma

Autologous stem cell transplant (ASCT) remains an integral part of the treatment strategy for many myeloma patients. The role of allogeneic stem cell transplant continues to be defined. There is increasing evidence that posttransplant maintenance therapy can significantly improve outcomes. It is predicted that with more routine use of cytogenetic and gene expression profiling in the future, we will be better able to identify those subgroups of patients who are expected to benefit most from early versus late versus no ASCT and those who will benefit from allogeneic stem cell transplant.

Allogeneic stem cell transplantation for multiple myeloma

Prospective trials comparing tandem autologous stem cell transplantation (ASCT) with ASCT followed by allogeneic stem cell transplantation (AlloSCT) have shown mixed results with regard to progression-free and overall survival rates. Thus, AlloSCT, although a potentially curative treatment, is not regarded as a standard treatment for multiple myeloma by most experts in the field. Strategies to improve the therapeutic index of the conditioning regimens have the potential to improve outcomes. Other approaches to modulate graft-versus-host disease while preserving or improving a graft-versus-myeloma effect could elevate AlloSCT to mainstream treatment. These approaches include vaccines, monoclonal antibodies, and adoptive immunotherapies.

In vivo T-cell depletion with antithymocyte globulins improves overall survival after myeloablative allogeneic stem cell transplantation in patients with hematologic disorders

To assess the effect of prophylactic treatment with antithymocyte globulin (ATG) on graft-versus-host disease (GvHD) in myeloablative transplant patients, we performed a meta-analysis of randomized and cohort studies. Medline, Embase, the Cochrane Controlled Trial Register and the Science Citation Index were searched for studies on ATG treatment in patients with hematologic disorders undergoing myeloablative transplantation. Four randomized controlled trials, six retrospective and one prospective cohort study were included, covering 1,549 patients. The summary hazard ratios (HRs) for overall survival were 0.84.

Chronic GVHD is associated with lower relapse risk irrespective of stem cell source among patients receiving transplantation from unrelated donors

Chronic GVHD (cGVHD) has been associated with reduced risk of relapse after allo-SCT for onco-hematological disease due to a graft-vs-malignancy effect. Here we retrospectively analyzed a series of 802 adult patients transplanted from unrelated donors and found that cGVHD was associated with significantly lower relapse and that the limited form was associated with a survival advantage: hazard ratio for OS=0.63 (0.46-0.87); P=0.004; this was due to combination of relapse reduction and similar non-relapse mortality with respect to patients without cGVHD. Importantly, the graft-vs-malignancy effect observed here did not differ when PBSC or BM were used as stem cell source, thus suggesting that the protective effect of limited cGVHD is similar after PBSC- or BM-based transplantation. These findings could have practical implications and suggest no qualitative difference between cGVHD occurring after transplantation performed with different stem cell sources.

The increase from 2.5 to 5 mg/kg of rabbit anti-thymocyte-globulin dose in reduced intensity conditioning reduces acute and chronic GVHD for patients with myeloid malignancies undergoing allo-SCT

We previously reported that reduced intensity conditioning (RIC) regimen with fludarabine, BU and 2.5 mg/kg of rabbit anti-thymocyte globulin (r-ATG) was effective but associated with a high rate of acute and chronic GVHD. Therefore, we increased the dose of r-ATG to 5 mg/kg. In this report, we analyzed 87 patients with AML or myelodysplastic syndrome (MDS) undergoing allo-SCT from an HLA-identical sibling donor from 2000 to 2010. RIC consisted of fludarabine, BU and r-ATG 2.5 mg/kg on 1 day (r-ATG1; n=53) or 2.5 mg/kg per day over 2 days (r-ATG2; n=22). Grade 2-4 acute GVHD incidence at day 100 was 30.2% and 8.8% in the r-ATG1 and r-ATG2 groups, respectively (P=0.038). Extensive chronic GVHD incidence was 60.4% and 12% in the r-ATG1 and r-ATG2 groups, respectively (P<0.001). The relapse incidences (RI) at 24 months were 18.9% and 28.5% in r-ATG1 and r-ATG2 groups, respectively (P=0.640). Overall and PFS were not different between the r-ATG1 and r-ATG2 groups. r-ATG dose at 5 mg/kg in the setting of RIC seems a good balance allowing GVHD prevention and antitumor effect with a remarkable reduction of GVHD incidence without an identical level of increased relapse rate.

Advances in the autologous and allogeneic transplantation strategies for multiple myeloma

BACKGROUND

Multiple myeloma is largely an incurable malignant plasma cell neoplasm; however, the landscape of its treatment is rapidly changing.

METHODS

The recent literature on both autologous and allogeneic transplant approaches for multiple myeloma was reviewed.

RESULTS

High-dose chemotherapy followed by autologous hematopoietic cell transplantation (HCT) remains an integral component of upfront treatment strategy, and the incorporation of novel immunomodulators and proteasome inhibitor to induction regimens improves response rates and increases overall survivals. Bortezomib and lenalidomide-based combination chemotherapy regimens have become the standard induction myeloma therapy. When myeloma patients proceed to transplant after novel combination regimens, their response rates are further improved. Despite these recent major improvements, myeloma remains incurable and long-term survival appears elusive. Due in part to a potential graft-vs-myeloma effect, allogeneic HCT is a potentially curative transplant option. However, initial attempts have been hampered by the high transplant-related mortality. With a reduction of toxicity, allogeneic transplant approaches with reduced-intensity conditioning have been utilized, although they are subject to continued disease progression and relapse following transplantation. Recent research efforts have shifted to the use of a tandem autologous-allogeneic HCT approach. The long-term follow-up of this new strategy is awaited.

CONCLUSIONS

Recent advances in HCT have improved outcomes of patients with multiple myeloma. Ongoing research activity focuses on the strategies to improve outcomes of HCT by incorporation of tandem autologous-allogeneic transplantation schema, novel conditioning regimens, and the use of consolidation and maintenance therapy.

Allogeneic hematopoietic cell transplant for multiple myeloma using reduced intensity conditioning therapy, 1998-2006: factors associated with improved survival outcome

This study reports on the outcome of 95 allogeneic hematopoietic cell transplants (HCTs) using reduced intensity conditioning (RIC) performed for patients with multiple myeloma (MM) in Australia and New Zealand between 1998 and 2006. The median age at HCT was 52 years. Of the 32 patients for whom the allograft was performed as a first transplant, 15 (47%) had their allograft less than 1 year from diagnosis, while for the 63 patients who had an allograft following an autograft, nine (14%) were allografted within 1 year post-diagnosis (p < 0.001). The cumulative incidence of transplant-related mortality (TRM) was 19% at 1 year post-transplant. At 5 years post-transplant the overall survival (OS) was 40% and progression-free survival (PFS) was 23%, with no apparent survival plateau. Three factors were independently favorable predictors of OS in a Cox regression model: immunoglobulin G (IgG) myeloma (hazard ratio [HR] = 0.42, 95% confidence interval [CI] 0.24-0.75, p = 0.004), a human leukocyte antigen (HLA)-identical sibling donor (HR = 0.37, 95% CI 0.18-0.74, p = 0.005), and less than 1 year between MM diagnosis and RIC HCT (HR = 0.27, 95% CI 0.12-0.59, p = 0.001). Patterns of outcome indicate that RIC HCT may offer the potential for cure for only a small group of patients with MM.

Reduced-intensity allogeneic hematopoietic stem cell transplantation for multiple myeloma: a concise review

Reduced-intensity conditioning (RIC) allogeneic hematopoietic stem cell transplantation (HSCT) can result in reliable donor engraftment, relatively low treatment-related mortality, and sustained remissions in the treatment of multiple myeloma. However, substantial cytoreduction pre-allografting is often necessary because of a variable graft-versus-myeloma effect. The use of RIC allogeneic HSCT immediately after autologous HSCT provides a temporal separation between tumor reduction by high-dose chemotherapy and the graft-versus-myeloma effect. There are currently a number of prospective trials attempting to address the issue of whether this strategy leads to decreases in relapse and/or improvement in overall survival as compared with double autologous transplants. Unfortunately, similar to autografting, relapse remains the major cause of treatment failure after RIC allogeneic HSCT. To improve treatment results with allografting, consideration should be given to incorporating immunomodulatory drugs and targeted treatments to enhance pretransplantation remission status, as posttransplantation maintenance therapy, or in combination with donor lymphocyte infusions for refractory or relapsed disease. Studies exploring these strategies are ongoing.

Unrelated stem cell transplantation for patients with multiple myeloma

PURPOSE OF REVIEW

The role of allogeneic stem cell transplantation (SCT) in treatment of myeloma patients is still controversial. Meanwhile, the numbers of unrelated SCT for hematological diseases in Europe are higher than for human leukocyte antigen (HLA)-identical sibling transplantations, but in multiple myeloma only 39% of the allogeneic transplantations are performed from unrelated donors and only a minority were done within prospective clinical trials.

RECENT FINDINGS

The few published data of unrelated SCT in multiple myeloma reported a higher treatment-related mortality for standard myeloablative conditioning in comparison to reduced-intensity conditioning. Despite the heterogeneous patient selection in the trial, lower nonrelapse mortality and improved survival can be achieved by careful donor selection (10/10 HLA-alleles, male donor). Natural killer-alloreactivity might play a role, but conclusive data are lacking. Transplantation in more advanced or refractory patients is associated with an inferior outcome. The results of an unrelated SCT seem to be comparable to those of HLA-identical siblings, but a direct comparison is lacking so far.

SUMMARY

Unrelated SCT in multiple myeloma is feasible, but prospective clinical trials using unrelated stem cell donors are urgently needed to define the role of an unrelated SCT in multiple myeloma in the era of novel agents.

International Myeloma Working Group Consensus Statement Regarding the Current Status of Allogeneic Stem-Cell Transplantation for Multiple Myeloma

Purpose

To define consensus statement regarding allogeneic stem-cell transplantation (Allo-SCT) as a treatment option for multiple myeloma (MM) on behalf of International Myeloma Working Group.

Patients and Methods

In this review, results from prospective and retrospective studies of Allo-SCT in MM are summarized.

Results

Although the introduction of reduced-intensity conditioning (RIC) has lowered the high treatment-related mortality associated with myeloablative conditioning, convincing evidence is lacking that Allo-RIC improves the survival compared with autologous stem-cell transplantation.

Conclusion

New strategies are necessary to make Allo-SCT safer and more effective for patients with MM. Until this is achieved, Allo-RIC in myeloma should only be recommended in the context of clinical trials.

EPOCH-F: a novel salvage regimen for multiple myeloma before reduced-intensity allogeneic hematopoietic SCT

There exists a need for effective salvage regimens for multiple myeloma patients being considered for reduced-intensity allogeneic hematopoietic SCT (RI-alloHSCT). We developed EPOCH-F, a regimen consisting of infusional etoposide, VCR and adriamycin with prednisone, CY and fludarabine to achieve both tumor control and host lymphocyte depletion to facilitate engraftment before RI-alloHSCT. In all, 22 multiple myeloma patients were treated with EPOCH-F before RI-alloHSCT. The median age was 53 years (range 36-65), and the median number of previous therapies was 2 (range 1-8). Patients received a median of three cycles (range 1-5) of EPOCH-F. Toxicities were primarily hematologic and manageable. Median lymphocyte counts decreased from 1423/μL (range 335-2788) to 519/μL (range 102-1420; P=0.0002). The overall response (≥PR) to EPOCH-F was 22 with 13% achieving a CR/near-complete response (nCR); only 1 patient progressed while on therapy. A total of 20 patients underwent RI-alloHSCT. Median day +100 donor chimerism was 100% (range 60-100). In all, 70% of patients achieved very good partial response or better response after transplant; 40% of patients achieved CR/nCR. TRM at 100 days and 5 years was 5 and 30%, respectively. Median OS after RI-alloHSCT was 46.1 months. EPOCH-F provides disease control and host lymphocyte depletion with consistent full donor engraftment in multiple myeloma patients undergoing RI-alloHSCT.

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.

Autologous-allogeneic tandem stem cell transplantation in patients with multiple myeloma

The decrease in treatment-related mortality by using reduced intensity conditioning and the well-proven immunological effect of the graft to multiple myeloma cells has increased the interest in using allogeneic stem cell transplantation in patients with multiple myeloma. The concept of a cytoreductive autograft followed by a dose-reduced allogeneic stem cell transplantation appears to be the most promising approach. Preliminary reports of several groups observed a treatment-related mortality at 1 year ranged from 0-17%. The rate of acute graft-vs.-host disease (GvHD) grade II-IV ranged from 32-44% and of chronic GvHD from 28-64%. The overall response rates for all studies ranged from 68-83%, including a high rate of complete remissions of 52-83%. The overall survival at 2 or 3 years was between 62% and 78%, and the progression-free survival between 54% and 56%. Despite the high rate of complete remissions after autologous-allogeneic tandem transplantation observed in nearly all trials, the relapse rate is quite considerable and exceeded nearly 40% at 2 years. Therefore, the reduced allogeneic treatment approach in patients with multiple myeloma has still to be improved and further preclinical and clinical research is focused on two major issues: (i) to further reduce treatment-related mortality and (ii) to enhance the remission status after transplantation, via adoptive immunotherapy inducing molecular remission and enhancing the cure rate of this approach.

Role of allogeneic stem cell transplantation in multiple myeloma

High-dose chemotherapy with autologous stem cell rescue has been regarded as the standard of care for young newly diagnosed myeloma patients. Moreover, the development of new agents with potent anti-tumor activity has further improved survival. However, relapse is a continuous risk primarily due to the inability of current therapies to eradicate all myeloma cells. Allografting is the only potentially curative treatment at least for a subset of multiple myeloma patients due to its well documented graft-versus-myeloma effects. Given the high transplant mortality of the high-dose myeloablative conditionings used until recently, allografting has for a long time been limited to younger relapsed/refractory patients. These limitations have been reduced significantly by the use of reduced-intensity conditionings. Although results of recent trials are encouraging, the subset of patients who may benefit most from an allograft remains to be determined. An overview of the clinical outcomes obtained with allografting and possible future developments are reported.

Plasma cell leukemia: a highly aggressive monoclonal gammopathy with a very poor prognosis

Plasma cell leukemia (PCL) is an aggressive variant of multiple myeloma and is characterized by the presence of >20% and/or an absolute number of greater 2 x 10(9)/L plasma cells circulating in the peripheral blood. PCL represents approximately 2-4% of all MM diagnosis and exists in two forms: primary PCL (PPCL, 60% of cases) presents de novo, whereas secondary PCL (SPCL, accounts for the remaining 40%) consists of a leukemic transformation in patients with a previously diagnosed MM. Because the mechanisms contributing to the pathogenesis of PCL are not fully understood, immunophenotyping, genetic evaluation (conventional karyotype, FISH, GEP and array-CGH), and immunohistochemistry are really important tools to investigate why plasma cells escape from bone marrow and become highly aggressive. Since treatment with standard agents and steroids is poorly effective, a combination of new drugs as part of the induction regimens and bone marrow transplant (autologous and allogeneic approaches) could nearly overcome the poor prognosis exhibited by PCL patients.

Treatment-emergent endocrine symptoms and the risk of breast cancer recurrence: a retrospective analysis of the ATAC trial

BACKGROUND

When the mechanism of action behind treatment toxicity reflects the intended effect on the treatment target, the toxicity might be a useful marker for efficacy. During endocrine treatment of breast cancer, the occurrence of symptoms related to oestrogen depletion or oestrogen blockade might thus be a predictor of treatment effectiveness. In this retrospective analysis, the relation between the reported incidence of vasomotor or joint symptoms and breast cancer recurrence in the Arimidex, Tamoxifen, Alone or in Combination (ATAC) trial is assessed.

METHODS

Women with hormone-receptor-positive tumours who reported vasomotor or joint symptoms at the first follow-up visit (3 months) in the ATAC trial, (which assessed tamoxifen or anastrozole for adjuvant treatment of postmenopausal breast cancer), were compared with women without these symptoms to see if there was a relation between these symptoms and subsequent recurrence. The ATAC trial is registered as an International Standard Randomised Controlled Trial, number ISRCTN18233230.

FINDINGS

1486 of 3964 (37.5%) eligible women reported newly emergent vasomotor symptoms at the 3-month follow-up visit and had lower subsequent recurrence than those who did not report these symptoms (223 during 10 752 women-years of follow-up vs 366 during 11 573 woman-years of follow-up, respectively; hazard ratio [HR] 0.84 [95% CI 0.71-1.00], p=0.04; adjusted for age, body-mass index, previous hormone-replacement therapy, nodal status, tumour size, and tumour grade). A greater decrease in breast-cancer recurrence was seen for the 1245 of 3964 (31.4%) eligible women who reported new joint symptoms at the 3-month follow-up visit compared with those not reporting these symptoms (158 during 9242 women-years of follow-up vs 366 during 11 573 women-years of follow-up; adjusted HR 0.60 [0.50-0.72], p<0.0001).

INTERPRETATION

The appearance of new vasomotor symptoms or joint symptoms within the first 3 months of treatment is a useful biomarker, suggesting a greater response to endocrine treatment compared with women without these symptoms. Awareness of the relation between early treatment-emergent symptoms and beneficial response to therapy might be useful when reassuring patients who present with them, and might help to improve long-term treatment adherence when symptoms cannot be alleviated effectively.

Feasibility of conditioning with thymoglobulin and reduced intensity TBI to reduce acute GVHD in recipients of allogeneic SCT

Murine studies using anti-T-cell antibodies for conditioning in allogeneic SCT demonstrate engraftment with low rates of GVHD. On the basis of this preclinical model, we conditioned 30 patients with advanced hematologic malignancies with rabbit antithymocyte globulin (ATG) and TBI, to reduce rates of fatal acute GVHD. Patients were enrolled in two sequential groups: cohort 1 received ATG 10 mg/kg in divided doses (days -4 to -1)+200 cGy TBI (n=16), and cohort 2 received ATG (days -10 to -7)+450 cGy TBI (n=14). Median donor blood chimerism for the combined group was 94, 93 and 93% in the first, second and third months after transplant. Only three developed grade II acute GVHD despite 43% of patients receiving unrelated donor transplants. One-year survival was 71+/-11 and 54+/-14%, respectively, in recipients of related and unrelated donor SCT. Donor lymphocyte infusions were needed in 12 patients for the management of relapse and for mixed donor-recipient chimerism in 4 patients. We conclude that 10 mg/kg ATG and TBI allows engraftment with a low risk of acute GVHD; however, further dose optimization of ATG is required to achieve a balance between GVHD and disease relapse.

Chimerism and T-cell receptor repertoire analysis after unrelated cord blood transplantation with a reduced-intensity conditioning regimen following autologous stem cell transplantation for multiple myeloma

A 65-year-old Japanese male was diagnosed as multiple myeloma with Bence Jones kappa type, clinical stage IIIA. His disease status reached partial remission after chemotherapy. Thereafter, he received tandem transplantation, consisting of high-dose chemotherapy with autologous stem cell transplantation (ASCT), followed by unrelated cord blood transplantation (U-CBT). U-CBT with a reduced-intensity conditioning regimen (RI-CBT) was performed in August 2003. HLA mismatch between the patient and the CBT donor was present at two serological loci (B and DR). A total nucleated CBT cell dose of 2.45 x 10(7)/kg body weight was infused on day 0. Graft-vs.-host disease (GVHD) prophylaxis consisted of cyclosporine A and short-term methotrexate. Neutrophil engraftment (>0.5 x 10(9)/l) was obtained on day 46. He developed positive cytomegalovirus antigenemia, grade II acute GVHD involving skin and liver, varicella-zoster virus infection, septic shock, hemorrhagic cystitis caused by adenovirus and acute hepatitis B virus infection after U-CBT. We retrospectively analyzed T-cell receptor (TCR) repertoire diversity and found that TCR repertoire diversity decreased continuously after U-CBT. Therefore, low-TCR repertoire diversity in this patient appears to be associated with various infections caused by immunodeficiency.

Role of stem cell transplantation

Hematopoietic stem cell transplantation (SCT) was introduced in the treatment of multiple myeloma in the 1980s. In the autologous setting, the use of peripheral blood stem cells instead of bone marrow has markedly improved feasibility. In fit patients who have normal renal function and are younger than 65 years of age, randomized studies have shown the superiority of autologous stem cell transplantation (ASCT) compared with conventional chemotherapy. ASCT is now considered the standard of care in this population of patients. It is currently challenged, however, by the introduction of novel agents, such as thalidomide, bortezomib, and lenalidomide. The role of allogenic SCT remains controversial, even with reduced intensity conditionings. Prospective studies still are needed to evaluate the impact of both autologous and allogeneic SCT in this new era.

Is there still a role for allogeneic stem-cell transplantation in multiple myeloma?

Despite significant improvements in survival for multiple myeloma patients through autologous stem-cell transplantation (SCT) and the introduction of novel drugs, the disease remains incurable for all but a small fraction of patients. Only allogeneic SCT is potentially curative, due in part to a graft-versus-myeloma effect. High transplant-related mortality with allogeneic SCT is currently the major limitation to wider use of this potentially curative modality. Mortality can be reduced through the use of lower-intensity conditioning regimens which allow engraftment of allogeneic stem cells, but this comes at a cost of higher rates of disease progression and relapse. Promising studies to improve outcomes of allogeneic transplants include the use of more intensive non-myeloablative conditioning regimens, tandem transplants, peripheral blood cells, graft engineering to improve the graft-versus-myeloma activity while reducing graft-versus-host disease (GVHD), post-transplant maintenance, and targeted conditioning therapies such as bone-seeking radioisotopes.

The allogeneic dilemma

The place of allogeneic SCT in the management of multiple myeloma remains controversial. Although it may induce long-term clinical and molecular remissions, the very high transplant-related toxicity after a myeloablative preparative regimen has limited its role to younger patients as first-line treatment option. Even with this limited indication, toxic death rate related to infections and GVHD is considered too high and this strategy has been almost abandoned. Reduced intensity conditioning (RIC) regimens look promising, as the transplant-related mortality is low even with matched unrelated donors and can be considered for older patients up to the age of 65 years. However when used in patients with a high tumor burden or with chemo-resistant disease, the immunologic effect of the graft is not sufficient to avoid relapses. Therefore, RIC allotransplantation is currently used after tumor mass reduction with high-dose therapy followed by autologous SCT. A recently published Italian study shows that this strategy induces better event-free survival than double autologous SCT due to a reduced relapse rate. The questions raised by this encouraging result are discussed in this paper.

Mini-Midi-Maxi? How to harness the graft-versus-myeloma effect and target molecular remission after allogeneic stem cell transplantation

Allogeneic stem cell transplantation in multiple myeloma after standard myeloablative conditioning induces a high rate of complete remissions, but long-term freedom from disease is achieved in 30-40% of the cases only. The therapeutic effect of allogeneic stem cell transplantation is due to cytotoxicity of high-dose chemotherapy and immune-mediated graft-versus-myeloma effect by donor T cells. Retrospective studies clearly suggest that both (a) reducing the intensity of high-dose chemotherapy by using reduced-intensity or non-myeloablative conditioning regimen or (b) reducing the immunotherapy of donor T cells by using T-cell depletion result in lower treatment-related morbidity and mortality, but also in higher rate of relapse. Therefore, this review will focus on potential strategies of how treatment-related morbidity and mortality might be kept low without an increased risk of relapse and how remission status after transplantation can be enhanced by using the newly established donor immunosystems after allografting as a platform for post-transplant treatment strategies with new drugs (thalidomide, lenalidomide, bortezomib) or immunotherapy (donor lymphocyte infusion, vaccination, tumor-specific T cells) in order to achieve remission on a molecular level, which seems to be a 'conditio sine qua non' to cure myeloma patients.

NY-ESO-1 immunotherapy for multiple myeloma

Most patients with poor-prognosis myeloma (abnormal metaphase cytogenetics) achieve excellent responses with tandem transplants, but the remissions are not durable. Novel interventions such as immunotherapy may eradicate the residual chemotherapy-resistant disease. Immunotherapy targeting weak antigens such as myeloma idiotype or tumor lysate has failed to produce clinically meaningful responses. We previously reported that the NY-ESO-1 antigen is expressed in >60% of poor-prognosis myeloma at diagnosis. Since NY-ESO-1 is highly immunogenic and is not expressed in most normal tissues, it is an ideal target for anti-myeloma immunotherapy. NY-ESO-1 based therapies are already being tested in clinical trials for a multitude of tumors. This review discusses the potential of NY-ESO-1 immunotherapy to improve outcome for myeloma.

Rabbit antithymocyte globulin inhibits monocyte-derived dendritic cells maturation in vitro and polarizes monocyte-derived dendritic cells towards tolerogenic dendritic cells expressing indoleamine 2,3-dioxygenase

BACKGROUND

Rabbit antithymocyte globulin (rATG) is a polyclonal mixture of immunoglobulin (Ig) G. It is used to prevent graft rejection and also graft versus host disease after transplantation. Its effect on lymphocyte function has been widely studied. Dendritic cells are central actors of the immune system. As antigen presenting cells, they are able to initiate, stimulate, and modulate immune responses.

METHODS

In this study, we investigated rATG effects on in vitro differentiation and maturation of monocyte-derived dendritic cells (Mo-DCs).

RESULTS

rATG inhibited maturation of immature Mo-DCs and allowed the generation of dendritic cells expressing ILT-3, CD123, CCR6 but not CCR7 and producing Indoleamine 2,3-dioxygenase mRNA as well as interferon-alpha.

CONCLUSION

rATG polarizes in vitro Mo-DCs towards tolerogenic dendritic cells.

The current status of reduced-intensity allogeneic hematopoietic stem cell transplantation for multiple myeloma

Of all the treatment modalities employed to control multiple myeloma, only allogeneic hematopoietic stem cell transplantation is potentially curative, due in large part to a graft-versus-myeloma (GVM) effect. Whereas patients who receive either allogeneic or autologous stem cell transplants for multiple myeloma have similar 3-5-year survival, only allograft recipients appear to enjoy long-term disease-free survival. High transplant-related mortality (TRM) associated with allogeneic stem cell transplantation is currently the major limitation to wider use of this potentially curative modality. This high mortality has been the major impetus for exploration of reduced intensity conditioning (RIC) regimens designed to allow engraftment of allogeneic stem cells. With follow-up now extending to 7 years, it is clear that when compared to myeloablative transplants, RIC allografts are associated with lower TRM; however, reduced mortality comes at a cost of higher rates of disease progression and relapse. Strategies designed to improve the therapeutic index of allografts include the use of more intensive, yet still non-myeloablative conditioning regimens, tandem autologous plus RIC allografts, peripheral blood cells rather than bone marrow, graft engineering to improve the GVM activity while reducing graft-versus-host disease, post-transplant maintenance and targeted conditioning therapies such as bone-seeking radioisotopes.

Early lymphocyte recovery predicts longer survival after autologous peripheral blood stem cell transplantation in multiple myeloma

To understand the prognostic value of lymphocyte recovery after autologous peripheral blood stem cell transplantation (APBSCT), we performed a retrospective study of 59 newly diagnosed multiple myeloma (MM) patients who underwent frontline APBSCT. Conditioning regimens were melphalan 100 mg/m(2) for 2 days. Following APBSCT, all patients showed complete or partial response. Median follow-up time was 29.57 months and median recovery of absolute lymphocyte count (ALC) > or =1000/mm(3) was 23 days. Univariate analysis revealed that significant predictors of overall survival (OS) included bone marrow (BM) plasma cells < or =40% at diagnosis (P=0.0243) and recovery of ALC > or =1000/mm(3) by day +23 (P=0.0156). Positive predictors for progression-free survival (PFS) were BM plasma cells < or =40% at diagnosis (P=0.0134) and recovery of ALC > or =1000/mm(3) by day +23 (P=0.0243). Absolute neutrophil count > or =1000/mm(3) on day +12 was marginally significant for OS and PFS (P=0.0821 and P=0.1153, respectively). Multivariate analysis showed that ALC > or =1000/mm(3) on day +23 independently predicted OS (P=0.031) and prolonged PFS (P=0.011), and that serum beta2-microglobulin was marginally significant for prolonged OS (P=0.066). In conclusion, ALC recovery was an independent predictor of both OS and PFS in MM.

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.