Heavy+light chain monitoring correlates with clinical outcome in multiple myeloma patients.

Novel anti-myeloma agents have improved patient response rates, which are historically based on reductions of the M-protein. These methods can be inaccurate for quantifying M-proteins at low concentrations. We compared the consistency and clinical impact of response assignment by electrophoretic and heavy+light chain (HLC) immunoassays post-consolidation in 463 newly diagnosed patients. The two methods gave similar assignments in patients with partial (PR; 79% agreement) or complete response (⩾CR; 92%). However, in patients achieving very good PR (VGPR) there was poor concordance between methods (45%). Median progression-free survival (PFS) for standard VGPR patients was 34.5 months; HLC responses stratified these patients further into PR, VGPR and ⩾CR, with median PFS of 21.3, 28.9 months and not reached, respectively; P<0.001. At this time, abnormal HLC ratios had better concordance with multiparametric flow cytometry (sensitivity 10-4) (37 and 34% positive, respectively), compared to immunofixation (62% positive). In addition, HLC-pair suppression was identified in 38% of patients and associated with shorter PFS (30.6 months vs not reached; P<0.001). We conclude that HLC monitoring could augment electrophoretic assessments in patients achieving VGPR. The prognostic significance of HLC responses might partly depend on the patients' ability to recover their immune system, as determined by normalisation of HLC measurements.

Expressed fusion gene landscape and its impact in multiple myeloma.

Multiple myeloma is a plasma cell malignancy characterized by recurrent IgH translocations and well described genomic heterogeneity. Although transcriptome profiles in multiple myeloma has been described, landscape of expressed fusion genes and their clinical impact remains unknown. To provide a comprehensive and detailed fusion gene cartography and suggest new mechanisms of tumorigenesis in multiple myeloma, we performed RNA sequencing in a cohort of 255 newly diagnosed and homogeneously treated multiple myeloma patients with long follow-up. Here, we report that patients have on average 5.5 expressed fusion genes. Kappa and lambda light chains and IgH genes are main partners in a third of all fusion genes. We also identify recurrent fusion genes that significantly impact both progression-free and overall survival and may act as drivers of the disease. Lastly, we find a correlation between the number of fusions, the age of patients and the clinical outcome, strongly suggesting that genomic instability drives prognosis of the disease.

Second primary malignancies in multiple myeloma: an overview and IMWG consensus.

Background: Therapeutic advancements following the introduction of autologous stem cell transplantation and 'novel' agents have significantly improved clinical outcomes for patients with multiple myeloma (MM). Increased life expectancy, however, has led to renewed concerns about the long-term risk of second primary malignancies (SPMs). This review outlines the most up-to-date knowledge of possible host-, disease-, and treatment-related risk factors for the development of SPMs in patients with MM, and provides practical recommendations to assist physicians. Design: A Panel of International Myeloma Working Group members reviewed the most relevant data published in the literature as full papers, or presented at meetings of the American Society of Clinical Oncology, American Society of Hematology, European Hematology Association, or International Myeloma Workshops, up to June 2016. Here, we present the recommendations of the Panel, based on this literature review. Results: Overall, the risk of SPMs in MM is low, multifactorial, and partially related to the length of patients' survival and MM intrinsic susceptibility. Studies suggest a significantly increased incidence of SPMs when lenalidomide is administered either following, or concurrently with, oral melphalan. Increased SPM incidence has also been reported with lenalidomide maintenance following high-dose melphalan, albeit to a lesser degree. In both cases, the risk of death from MM was significantly higher than the risk of death from SPMs, with lenalidomide possibly providing a survival benefit. No increase in SPM incidence was reported with lenalidomide plus dexamethasone (without melphalan), or with bortezomib plus oral melphalan, dexamethasone, or thalidomide. Conclusion: In general, the risk of SPMs should not alter the current therapeutic decision-making process in MM. However, regimens such as lenalidomide plus dexamethasone should be preferred to prolonged exposure to lenalidomide plus oral melphalan. SPM risk should be carefully discussed with the patient in the context of benefits and risks of different treatment options.

Safe and prolonged survival with long-term exposure to pomalidomide in relapsed/refractory myeloma.

BACKGROUND: The IFM2009-02 trial studied pomalidomide (4 mg daily, 21/28 versus 28/28) and dexamethasone in very advanced relapsed or refractory multiple myeloma (RRMM). We observed that 40% of patients had a prolonged progression-free survival (PFS) and subsequently overall survival (OS). We sought to analyze the characteristics of these patients and study the effect of long exposure to pomalidomide. DESIGN: We separated the studied population into two groups: 3 months to 1 year (<1 year) and more than 1 year (≥1 year) of treatment with pomalidomide and dexamethasone based on clinical judgment and historical control studies. We then analyzed the characteristics of patients according to duration of treatment. RESULTS: The overall response rate (ORR) for the <1-year group was 43%, the median PFS 4.6 months [95% confidence interval (95% CI) 3.8-6.4] with only 6% at 12 months, and the median OS was 15 months (11.7-20.3) and 40% at 18 months. For the ≥1-year group, the response rate and survival were strikingly different, ORR at 83%, median PFS 20.7 months (14.7-35.4), median OS not reached, and 91% at 18 months. CONCLUSION: Pomalidomide and dexamethasone favored prolonged and safe exposure to treatment in 40% of heavily treated and end-stage RRMM, a paradigm shift in the natural history of RRMM characterized with a succession of shorter disease-free intervals and ultimately shorter survival. Although an optimization of pomalidomide-dexamethasone regimen is warranted in advanced RRMM, we claim that pomalidomide has proven once more to change the natural history of myeloma in this series, which should be confirmed in a larger study.

Consolidation and maintenance therapy for multiple myeloma after autologous transplantation: where do we stand?

Novel agents including proteasome inhibitors and immunomodulatory drugs are now routinely utilized as part of the induction regimen before transplantation and this has resulted in substantial improvements in the depth of response achieved before transplant. Given that depth of response is prognostic for overall outcome, a number of studies have been conducted or are ongoing to investigate the use of novel agents as consolidation and maintenance therapy after transplant. Most clinical trials have reported after consolidation and maintenance therapy an increased PFS and even overall survival in some of them. The use of post-autologous stem cell transplant consolidation and maintenance is an increasingly attractive concept. However, some side effects could be observed with such long-term therapy and many open questions are still under debate. The decision to administer consolidation and/or maintenance therapy will likely need to be guided by the individual patient situation. This review aims to analyze the currently available research evidence in this field.

Trends in autologous hematopoietic cell transplantation for multiple myeloma in Europe: increased use and improved outcomes in elderly patients in recent years.

Autologous hematopoietic cell transplantation (AHCT) is a standard of care in multiple myeloma (MM) patients aged <65 years. To understand age-related trends in utilisation and outcome of AHCT, we analysed 53 675 MM patients who underwent a first AHCT in 31 European countries between 1991 and 2010. The number of patients undergoing AHCT increased for all age groups (<40, 40-49, 50-59, 60-64, 65-69 and ⩾70 years) throughout the observation period. The highest increase was observed for patients aged ⩾65 years, who accounted for 3% of AHCTs in 1991-1995 and for 18.8% of AHCTs in 2006-2010. Risk factors associated with survival over the entire observation period (P<0.001) were calendar period, remission status at AHCT, gender, disease duration before AHCT and age. Survival improved considerably more in older than in younger patients in recent years. In 2006-2010, median 2- and 5-year post-transplant survival ranged from 85.9 and 61.5% in patients <40 years to 80.2 and 49.7% in those ⩾70 years. All-cause day-100 mortality decreased throughout the observation period to ⩽2.4% for all age groups in 2006-2010. The results of this study demonstrate increased utilisation and safety of AHCT with improved post-transplant survival particularly in elderly MM patients in recent years in Europe.

Use of G-CSF to hasten neutrophil recovery after auto-SCT for AML is not associated with increased relapse incidence: a report from the Acute Leukemia Working Party of the EBMT.

Application of G-CSF in AML is controversial as leukemic blasts may express receptors interacting with the cytokine, which may stimulate leukemia growth. We retrospectively analyzed the impact of G-CSF use to accelerate neutrophil recovery after auto-SCT on outcome. Adults with AML in first CR autografted between 1994 and 2010 were included. Nine hundred and seventy two patients were treated with G-CSF after auto-SCT whereas 1121 were not. BM and PB were used as a source of stem cells in 454 (22%) and 1639 (78%) cases, respectively. The incidence of relapse at 5 years in the BM-auto-SCT group was 38% for patients receiving post-transplant G-CSF and 43% for those not treated with G-CSF, P=0.46. In the PB-auto-SCT cohort, respective probabilities were 48% and 49%, P=0.49. No impact of the use of G-CSF could be demonstrated with respect to the probability of leukemia-free survival: in the BM-auto-SCT group, 51% for G-CSF(+) and 48% for G-CSF(-), P=0.73; in PB-auto-SCT group, 42% for G-CSF(+) and 43% for G-CSF(-), P=0.83. Although G-CSF administration significantly shortened the neutropenic phase, no beneficial effect was observed with regard to non-relapse mortality. In patients with AML, the use of G-CSF after auto-SCT is not associated with increased risk of relapse irrespective of the source of stem cells used.

Matched unrelated donor allogeneic transplantation provides comparable long-term outcome to HLA-identical sibling transplantation in relapsed diffuse large B-cell lymphoma.

The objective of this retrospective analysis was to compare outcomes of patients with diffuse large B-cell lymphoma (DLBCL) who received either a matched sibling (sib) or an unrelated donor (URD) allogeneic hematopoietic cell transplantation (allo-HCT). Long-term outcome of 172 DLBCL patients receiving URD-HCT between 2000 and 2007 and reported to the European Group for Blood and Marrow Transplantation, was compared with that of 301 subjects, allografted from sib-HCT. With a median follow-up of 45 months, 3-year PFS approached 35% for both groups; overall survival (OS) was 42% for sib-HCT versus 37% for URD (NS). Multivariate analyses confirmed that donor type was not associated with differences in non-relapse mortality (NRM), relapse rate (RR), PFS or OS. Poor performance status (PS) and refractory disease adversely affected PFS and OS. Prior auto-SCT and multiple previous therapies predicted for shorter PFS. NRM was adversely affected by older age (⩾50 years), poor PS and refractory disease, and RR by time from diagnosis to allo-HCT of <36 months, prior auto-SCT, refractory disease, poor PS and in vivo T-cell depletion with alemtuzumab. This large study shows for the first time that URD-HCT is not inferior to sib-HCT, providing a reasonable therapeutic approach for DLBCL patients, having no HLA-identical sibling available.

Impact of in vivo T-cell depletion on outcome of AML patients in first CR given peripheral blood stem cells and reduced-intensity conditioning allo-SCT from a HLA-identical sibling donor: a report from the Acute Leukemia Working Party of the European Group for Blood and Marrow Transplantation.

The impact of in vivo T-cell depletion on transplantation outcomes in patients transplanted with reduced-intensity conditioning (RIC) remains controversial. This study assessed the outcome of 1250 adult patients with de novo AML in first CR (CR1) given PBSC from HLA-identical siblings after chemotherapy-based RIC. A total of 554 patients did not receive any form of in vivo T-cell depletion (control group), whereas antithymocyte globulin (ATG) and alemtuzumab were given in 444 and 252 patients, respectively. The incidences of grade II-IV acute GVHD were 21.4, 17.6 and 10.2% in control, ATG and alemtuzumab patients, respectively (P<0.001). In multivariate analysis, the use of ATG and the use of alemtuzumab were each associated with a lower risk of chronic GVHD (P<0.001 each), but a similar risk of relapse, and of nonrelapse mortality, and similar leukemia-free survival and OS. Further, among patients given BU-based RIC, the use of <6 mg/kg ATG did not increase the risk of relapse (hazard ratio, HR=1.1), whereas there was a suggestion for higher relapse risk in patients given 6 mg/kg ATG (HR=1.4, P=0.08). In summary, these data suggest that a certain amount of in vivo T-cell depletion can be safely used in the conditioning of AML patients in CR1 given PBSC after chemotherapy-based RIC.

Deletion of the 1p32 region is a major independent prognostic factor in young patients with myeloma: the IFM experience on 1195 patients.

Deletions of the 1p region appear as a pejorative prognostic factor in multiple myeloma patients (especially 1p22 and 1p32 deletions) but there is a lack of data on the real impact of 1p abnormalities on an important and homogeneous group of patients. To address this issue we studied by fluorescence in situ hybridization (FISH) the incidence and prognostic impact of 1p22 and 1p32 deletions in 1195 patients from the IFM (Institut Francophone du Myélome) cell collection. Chromosome 1p deletions were present in 23.3% of the patients (271): 15.1% (176) for 1p22 and 7.3% (85) for 1p32 regions. In univariate analyses, 1p22 and 1p32 appeared as negative prognostic factors for progression-free survival (PFS): 1p22: 19.8 months vs 33.6 months (P<0.001) and 1p32: 14.4 months vs 33.6 months (P<0.001); and overall survival (OS): 1p22: 44.2 months vs 96.8 months (P=0.002) and 1p32: 26.7 months vs 96.8 months (P<0.001). In multivariate analyses, 1p22 and 1p32 deletions still appear as independent negative prognostic factors for PFS and OS. In conclusion, our data show that 1p22 and 1p32 deletions are major negative prognostic factors for PFS and OS for patients with MM. We thus suggest that 1p32 deletion should be tested for all patients at diagnosis.

The outcome of reduced intensity allogeneic stem cell transplantation and autologous stem cell transplantation when performed as a first transplant strategy in relapsed follicular lymphoma: an analysis from the Lymphoma Working Party of the EBMT.

Both auto-SCT and reduced intensity allo-SCT (RIST) are employed in the treatment of relapsed follicular lymphoma (FL). We have analysed the outcome of these two transplant procedures when used as a first transplant in this setting. We conducted a retrospective comparison of 726 patients who underwent an auto-SCT and 149 who underwent a RIST as a first transplant procedure for relapsed FL as reported to the Lymphoma Working Party of the European Bone Marrow Transplant. The non-relapse mortality (NRM) was significantly worse for patients undergoing a RIST (relative risk (RR) 4.0, P<0.001). The 1-year NRM was 15% for those undergoing a RIST compared with 3% for those undergoing an auto-SCT. Disease relapse or progression were significantly worse for those receiving an auto-SCT (RR 3.1, P<0.001). Patients undergoing a RIST had a 5-year relapse rate of 20% compared with 47% for those undergoing an auto-SCT. The PFS at 5 years was 57% for patients receiving a RIST compared with 48% for those receiving an auto-SCT. There was no significant difference in OS between the two groups. RIST is associated with a higher NRM and lower relapse rate in patients with relapsed FL.

Combining fluorescent in situ hybridization data with ISS staging improves risk assessment in myeloma: an International Myeloma Working Group collaborative project.

The combination of serum ß2-microglobulin and albumin levels has been shown to be highly prognostic in myeloma as the International Staging System (ISS). The aim of this study was to assess the independent contributions of ISS stage and cytogenetic abnormalities in predicting outcomes. A retrospective analysis of international studies looking at both ISS and cytogenetic abnormalities was performed in order to assess the potential role of combining ISS stage and cytogenetics to predict survival. This international effort used the International Myeloma Working Group database of 12 137 patients treated worldwide for myeloma at diagnosis, of whom 2309 had cytogenetic studies and 5387 had analyses by fluorescent in situ hybridization (iFISH). Comprehensive analyses used 2642 patients with sufficient iFISH data available. Using the comprehensive iFISH data, combining both t(4;14) and deletion (17p), along with ISS stage, significantly improved the prognostic assessment in terms of progression-free survival and overall survival. The additional impact of patient age and use of high-dose therapy was also demonstrated. In conclusion, the combination of iFISH data with ISS staging significantly improves risk assessment in myeloma.

Prognostic utility of intact immunoglobulin Ig'κ/Ig'λ ratios in multiple myeloma patients.

To determine whether isotype matched immunoglobulin (Ig; Ig'κ/Ig'λ) ratios had prognostic significance in patients with intact Ig multiple myeloma (MM). Novel immunoassays measuring serum concentrations of the Ig heavy chain/light chain (HLC) subsets IgGκ, IgGλ, IgAκ and IgAλ were compared with monoclonal protein ('M-spike') quantification by serum protein electrophoresis, ß(2)-microglobulin (ß(2)-M), albumin, serum free light chain (FLC) and cytogenetic markers in relation to outcome in 339 MM patients. Abnormal IgGκ/IgGλ and IgAκ/IgAλ ratios present in the respective tumor isotypes at clinical presentation were predictive of shorter progression-free survival (PFS) (hazard ratio (HR) 1.9; P=0.0002), predominantly due to the suppression of the uninvolved (polyclonal) Ig of the same isotype as the tumor (HR 1.8; P=0.002). No significant associations were observed between PFS and M-spike concentrations, suppression of non-tumor Igs of different isotypes or FLC κ/λ ratios. ß(2)-M and HLC ratios were independently prognostic (P=0.045 and P=0.001). A staging system using ß(2)-M and extreme HLC ratios (<0.01 or >200) had greater prognostic value than the widely used ISS staging system (HR 1.7; P=0.00002 vs HR 1.3; P=0.017). These results suggest that HLC ratios may have a role in clinical management of MM.

A 4-weekly course of rituximab is safe and improves tumor control for patients with minimal residual disease persisting 3 months after autologous hematopoietic stem-cell transplantation: results of a prospective multicenter phase II study in patients with follicular lymphoma.

BACKGROUND: This study explored the efficacy and safety of rituximab as treatment of clinical or molecular residual disease after autologous stem-cell transplantation (ASCT) in follicular lymphoma (FL). PATIENTS AND METHODS: Forty patients with CD20+ FL and clinically (group A, n = 14) or clono-specific PCR-detectable (group B, n = 25) residual disease persisting 3 months after ASCT received rituximab 375 mg/m² once weekly for 4 weeks. RESULTS: Response rate at day 50 was 36% [90% confidence interval (CI) 15-61] in group A (World Health Organization criteria) and 52% (90% CI 34-70) in group B (conversion PCR-undetectable status to undetectable status). The best response rate was 71% [nine complete responses (CRs) and one partial response] in group A and 76% in group B. At 36 months, all 10 responses persisted in group A, whereas 46% of patients in group B still had PCR-undetectable disease. Furthermore, 68% of patients in group B were still in clinical CR. Rituximab after ASCT was safe with few grade 3-4 toxic effects (15% patients), mainly acute reactions and infections. CONCLUSION: Rituximab induced a high rate of durable CRs in patients with clinically detectable disease, as well as durable eradication of PCR-detectable disease in patients with FL after ASCT. Continued molecular responses assessed with a highly sensitive and clono-specific PCR technique were correlated with an excellent disease control.

Autologous stem-cell transplantation in patients with mantle cell lymphoma beyond 65 years of age: a study from the European Group for Blood and Marrow Transplantation (EBMT).

BACKGROUND: Limited experience is available on the feasibility and efficacy of autologous stem-cell transplantation (ASCT) in patients with mantle cell lymphoma (MCL) beyond 65 years. DESIGN AND METHODS: We analysed 712 patients with MCL treated with ASCT from 2000 to 2007 and reported to the European Group for Blood and Marrow Transplantation registry. Patients>65 years were compared with patients<65 years for the end points non-relapse mortality (NRM), relapse incidence, progression-free survival (PFS), and overall survival (OS). RESULTS: Seventy-nine patients were ≥65 years old. Median time from diagnosis to ASCT was longer in the elderly patients (11 versus 9 months, P=0.005); they had more commonly received at least two treatment lines (62.0% versus 47.9%, P=0.02) and were less commonly in first complete remission at ASCT (35.4% versus 51.2%, P=0.002). Median follow-up after ASCT was 19 and 25 months, respectively. NRM was comparable at 3 months (3.8% versus 2.5%) and at 5 years (5.6% versus 5.0%). There were no differences in relapse rate (66% versus 55% at 5 years), PFS (29% versus 40%) and OS (61% versus 67%) between both populations of patients. CONCLUSION: ASCT beyond 65 years of age is feasible in selected patients with MCL and results in similar disease control and survival as in younger patients.

New developments in conditioning regimens before auto-SCT in multiple myeloma.

The current standard conditioning regimen before auto-SCT in patients with multiple myeloma is melphalan 200 mg/m(2). Several attempts have recently been made to improve this aspect of the high-dose therapy procedure. The scope of this review article is to summarize current knowledge on conditioning regimens in this setting.

Optimizing the use of lenalidomide in relapsed or refractory multiple myeloma: consensus statement.

An expert panel convened to reach a consensus regarding the optimal use of lenalidomide in combination with dexamethasone (Len/Dex) in patients with relapsed or refractory multiple myeloma (RRMM). On the basis of the available evidence, the panel agreed that Len/Dex is a valid and effective treatment option for most patients with RRMM. As with other therapies, using Len/Dex at first relapse is more effective regarding response rate and durability than using it after multiple salvage therapies. Len/Dex may be beneficial regardless of patient age, disease stage and renal function, although the starting dose of lenalidomide should be adjusted for renal impairment and cytopenias. Long-term treatment until there is evidence of disease progression may be recommended at the best-tolerated doses of both lenalidomide and dexamethasone. Recommendations regarding the prevention and management of adverse events, particularly venous thromboembolism and myelosuppression, were provided on the basis of the available evidence and practical experience of panel members. Ongoing trials will provide more insight into the effects of continuous lenalidomide-based therapy in myeloma.