RAS/RAFlandscape in monoclonal plasma cell conditions.

Multiple Myeloma (MM) is characterized by a huge heterogeneity at the molecular level. The RAS/RAF pathway is the most frequently mutated, in about 50% of the patients. However, these mutations are frequently subclonal, suggesting a secondary event. Since these genes are part of our routine next-generation sequencing (NGS) panel, we analyzed >10,000 patients with different plasma cell disorders in order to describe the RAS/RAF landscape. In this large cohort of patients, almost 61% of the patients presented a RAS/RAF mutation at diagnosis or relapse, but much lower frequencies in pre-symptomatic cases. Of note, the mutations were different from that observed in solid tumors (higher proportions of Q61 mutations). In 29 patients with two different mutations, we were able to perform single cell sequencing, showing that in most cases, mutations occurred in different subclones, suggesting an ongoing mutational process. These findings suggest that RAS/RAF pathway is not an attractive target, both on therapeutic and residual disease assessment points of vue.

In Multiple Myeloma, High-Risk Secondary Genetic Events Observed at Relapse Are Present From Diagnosis in Tiny, Undetectable Subclonal Populations.

PURPOSE: Multiple myeloma (MM) is characterized by copy number abnormalities (CNAs), some of which influence patient outcomes and are sometimes observed only at relapse(s), suggesting their acquisition during tumor evolution. However, the presence of micro-subclones may be missed in bulk analyses. Here, we use single-cell genomics to determine how often these high-risk events are missed at diagnosis and selected at relapse. MATERIALS AND METHODS: We analyzed 81 patients with plasma cell dyscrasias using single-cell CNA sequencing. Sixty-six patients were selected at diagnosis, nine at first relapse, and six in presymptomatic stages. A total of 956 newly diagnosed patients with MM and patients with first relapse MM have been identified retrospectively with required cytogenetic data to evaluate enrichment of CNA risk events and survival impact. RESULTS: A total of 52,176 MM cells were analyzed. Seventy-four patients (91%) had 2-16 subclones. Among these patients, 28.7% had a subclone with high-risk features (del(17p), del(1p32), and 1q gain) at diagnosis. In a patient with a subclonal 1q gain at diagnosis, we analyzed the diagnosis, postinduction, and first relapse samples, which showed a rise of the high-risk 1q gain subclone (16%, 70%, and 92%, respectively). In our clinical database, we found that the 1q gain frequency increased from 30.2% at diagnosis to 43.6% at relapse (odds ratio, 1.78; 95% CI, 1.58 to 2.00). We subsequently performed survival analyses, which showed that the progression-free and overall survival curves were superimposable between patients who had the 1q gain from diagnosis and those who seemingly acquired it at relapse. This strongly suggests that many patients had 1q gains at diagnosis in microclones that were missed by bulk analyses. CONCLUSION: These data suggest that identifying these scarce aggressive cells may necessitate more aggressive treatment as early as diagnosis to prevent them from becoming the dominant clone.

Biallelic deletion of 1p32 defines ultra-high-risk myeloma, but monoallelic del(1p32) remains a strong prognostic factor.

Cytogenetic abnormalities (CAs) are known to be the preponderant prognostic factor in multiple myeloma. Our team has recently developed a prognostic score based on 6 CAs, with which del(1p32) appears to be the second worst abnormality after del(17p). This study aimed to confirm the adverse effect of 1p32 deletion in patients with newly diagnosed multiple myeloma (NDMM). Among 2551 patients with newly diagnosed multiple myeloma, 11% were harboring del(1p32). Their overall survival (OS) was significantly inferior compared with patients without del(1p32) (median OS: 49 months vs 124 months). Likewise, progression-free survival was significantly shorter. More importantly, biallelic del(1p32) conferred a dramatically poorer prognosis than a monoallelic del(1p32) (median OS: 25 months vs 60 months). As expected, the OS of patients with del(1p32) significantly decreased when this abnormality was associated with other high-risk CAs [del(17p), t(4;14), or gain(1q)]. In the multivariate analysis, del(1p32) appeared as a negative prognostic factor; after adjustment for age and treatment, the risk of progression was 1.3 times higher among patients harboring del(1p32), and the risk of death was 1.9 times higher. At the dawn of risk-adapted treatment strategies, we have confirmed the adverse effect of del(1p32) in multiple myeloma and the relevance of its assessment at diagnosis.

Bortezomib and high-dose melphalan conditioning regimen in frontline multiple myeloma: an IFM randomized phase 3 study.

High-dose melphalan (HDM) and transplantation are recommended for eligible patients with multiple myeloma. No other conditioning regimen has proven to be more effective and/or safer. We previously reported in a phase 2 study that bortezomib can safely and effectively be combined with HDM (Bor-HDM), with a 32% complete response (CR) rate after transplantation. These data supported a randomized phase 3 trial. Randomization was stratified according to risk and response to induction: 300 patients were enrolled, and 154 were allocated to the experimental arm (ie, arm A) with bortezomib (1 mg/m2 intravenously [IV]) on days -6, -3, +1, and +4 and melphalan (200 mg/m2 IV) on day -2. The control arm (ie, arm B) consisted of HDM alone (200 mg/m2 IV). There were no differences in stringent CR + CR rates at day 60 posttransplant (primary end point): 22.1% in arm A vs 20.5% in arm B (P = .844). There were also no differences in undetectable minimum residual disease rates: 41.3% vs 39.4% (P = .864). Median progression-free survival was 34.0 months for arm A vs 29.6 months for arm B (adjusted HR, 0.82; 95% CI, 0.61-1.13; P = .244). The estimated 3-year overall survival was 89.5% in both arms (hazard ratio, 1.28; 95% CI, 0.62-2.64; P = .374). Sixty-nine serious adverse events occurred in 18.7% of Bor-HDM-treated patients (vs 13.1% in HDM-treated patients). The proportion of grade 3/4 AEs was similar within the 2 groups (72.0% vs 73.1%), mainly (as expected) blood and gastrointestinal disorders; 4% of patients reported grade 3/4 or painful peripheral neuropathy in arm A (vs 1.5% in arm B). In this randomized phase 3 study, a conditioning regimen with Bor-HDM did not improve efficacy end points or outcomes compared with HDM alone. The original trial was registered at www.clinicaltrials.gov as #NCT02197221.

Primary plasma cell leukemias displaying t(11;14) have specific genomic, transcriptional, and clinical features.

Primary plasma cell leukemia (pPCL) is an aggressive form of multiple myeloma (MM) that has not benefited from recent therapeutic advances in the field. Because it is very rare and heterogeneous, it remains poorly understood at the molecular level. To address this issue, we performed DNA and RNA sequencing of sorted plasma cells from a large cohort of 90 newly diagnosed pPCL and compared with MM. We observed that pPCL presents a specific genomic landscape with a high prevalence of t(11;14) (about half) and high-risk genomic features such as del(17p), gain 1q, and del(1p32). In addition, pPCL displays a specific transcriptome when compared with MM. We then wanted to characterize specifically pPCL with t(11;14). We observed that this subentity displayed significantly fewer adverse cytogenetic abnormalities. This translated into better overall survival when compared with pPCL without t(11;14) (39.2 months vs 17.9 months, P = .002). Finally, pPCL with t(11;14) displayed a specific transcriptome, including differential expression of BCL2 family members. This study is the largest series of patients with pPCL reported so far.

AA amyloidosis complicating monoclonal gammopathies, an unusual feature validating the concept of "monoclonal gammopathy of inflammatory significance"?

INTRODUCTION: AL amyloidosis is caused by the proliferation of an immunoglobulin-secreting B cell clone. AA amyloidosis is a rare complication of chronic inflammation. However, some patients present with diseases combining monoclonal immunoglobulin production and chronic inflammation. The aim of this work was to describe cases of AA amyloidosis associated with monoclonal gammopathies. PATIENTS AND METHODS: We reviewed all patients reported in French national amyloid centres presenting with AA amyloidosis and monoclonal gammopathy and performed a literature review. The quality of AA amyloidosis diagnosis and the causal relationship with monoclonal gammopathy were assessed. RESULTS: In total, four patients from our centres and eight from the literature fulfilled the inclusion criteria. The haematological disorders presenting with monoclonal gammopathy were as follows: Waldenström macroglobulinaemia (n = 8), Schnitzler syndrome (n = 2), multiple myeloma (n = 1) and monoclonal gammopathy of undetermined significance (n = 1). Treatment strategies varied among the cases, with the treatment of the haematological disorder in 4 and anti-inflammatory treatment in 2. CONCLUSION: Monoclonal gammopathies might be a rare and poorly known cause of AA amyloidosis. Such monoclonal gammopathies could be named "monoclonal gammopathies of inflammatory significance."

del(17p) without TP53 mutation confers a poor prognosis in intensively treated newly diagnosed patients with multiple myeloma.

Despite tremendous improvements in the outcome of patients with multiple myeloma in the past decade, high-risk patients have not benefited from the approval of novel drugs. The most important prognostic factor is the loss of parts of the short arm of chromosome 17, known as deletion 17p (del(17p)). A recent publication (on a small number of patients) suggested that these patients are at very high-risk only if del(17p) is associated with TP53 mutations, the so-called "double-hit" population. To validate this finding, we designed a much larger study on 121 patients presenting del(17p) in > 55% of their plasma cells, and homogeneously treated by an intensive approach. For these 121 patients, we performed deep next generation sequencing targeted on TP53. The outcome was then compared with a large control population (2505 patients lacking del(17p)). Our results confirmed that the "double hit" situation is the worst (median survival = 36 months), but that del(17p) alone also confers a poor outcome compared with the control cohort (median survival = 52.8 months vs 152.2 months, respectively). In conclusion, our study clearly confirms the extremely poor outcome of patients displaying "double hit," but also that del(17p) alone is still a very high-risk feature, confirming its value as a prognostic indicator for poor outcome.

Development and Validation of a Cytogenetic Prognostic Index Predicting Survival in Multiple Myeloma.

PURPOSE: The wide heterogeneity in multiple myeloma (MM) outcome is driven mainly by cytogenetic abnormalities. The current definition of high-risk profile is restrictive and oversimplified. To adapt MM treatment to risk, we need to better define a cytogenetic risk classification. To address this issue, we simultaneously examined the prognostic impact of del(17p); t(4;14); del(1p32); 1q21 gain; and trisomies 3, 5, and 21 in a cohort of newly diagnosed patients with MM. METHODS: Data were obtained from 1,635 patients enrolled in four trials implemented by the Intergroupe Francophone du Myélome. The oldest collection of data were used for model development and internal validation. For external validation, one of the two independent data sets was used to assess the performance of the model in patients treated with more current regimens. Six cytogenetic abnormalities were identified as clinically relevant, and a prognostic index (PI) that was based on the parameter estimates of the multivariable Cox model was computed for all patients. RESULTS: In all data sets, a higher PI was consistently associated with a poor survival outcome. Dependent on the validation cohorts used, hazard ratios for patients in the high-risk category for death were between six and 15 times higher than those of patients in the low-risk category. Among patients with t(4;14) or del(17p), we observed a worse survival in those classified in the high-risk category than in those in the intermediate-risk category. The PI showed good performance for discriminating between patients who died and those who survived (Harrell's concordance index greater than 70%). CONCLUSION: The cytogenetic PI improves the classification of newly diagnosed patients with MM in the high-risk group compared with current classifications. These findings may facilitate the development of risk-adapted treatment strategies.

Pomalidomide, cyclophosphamide, and dexamethasone for relapsed multiple myeloma.

It is important to have an effective therapy for patients with multiple myeloma (MM) at first relapse, particularly if an autologous stem cell transplant (ASCT) is considered at this stage. This multicenter, phase 2 trial evaluated the efficacy and safety of weekly oral pomalidomide-cyclophosphamide-dexamethasone (PCD) in patients with MM in first relapse after treatment with lenalidomide-bortezomib-dexamethasone (RVD). All patients had received RVD as induction and consolidation therapy, plus lenalidomide maintenance for 1 year (arm A). Half had also received an ASCT after induction (arm B). At MM relapse, all patients received 4 oral cycles of pomalidomide 4 mg (days 1-21), cyclophosphamide 300 mg (days 1, 8, 15, and 22), and dexamethasone 40 mg (days 1-4 and days 15-18 of a 28-day cycle; PCD). Responding patients in arm A underwent ASCT and received 2 additional cycles of PCD, whereas those in arm B received 5 cycles of PCD. All patients received pomalidomide-dexamethasone maintenance until disease progression. Primary end point was partial remission or better after the initial 4 cycles of PCD. Responses were obtained in 82/97 (85%) patients evaluated: complete remission (n = 1; 1%), very good partial remission (n = 32; 33%), and partial remission (n = 49; 51%). Three patients (3%) had stable disease, and 6 (6%) had disease progression (6 response failures). Forty-five (94%) of the 48 patients in arm A underwent planned ASCT. PCD was effective therapy after first relapse with RVD. After 4 cycles, the rate of partial remission or better was 85%, and 94% of planned ASCTs were performed. Toxicity was mostly hematologic and manageable. This trial was registered at www.clinicaltrials.gov as #NCT02244125.

Minimal residual disease negativity using deep sequencing is a major prognostic factor in multiple myeloma.

The introduction of novel agents has led to major improvements in clinical outcomes for patients with multiple myeloma. To shorten evaluation times for new treatments, health agencies are currently examining minimal residual disease (MRD) as a surrogate end point in clinical trials. We assessed the prognostic value of MRD, measured during maintenance therapy by next-generation sequencing (NGS). MRD negativity was defined as the absence of tumor plasma cell within 1 000 000 bone marrow cells (<10-6). Data were analyzed from a recent clinical trial that evaluated the role of transplantation in newly diagnosed myeloma patients treated with lenalidomide, bortezomib, and dexamethasone (RVD). MRD negativity was achieved at least once during maintenance in 127 patients (25%). At the start of maintenance therapy, MRD was a strong prognostic factor for both progression-free survival (adjusted hazard ratio, 0.22; 95% confidence interval, 0.15-0.34; P < .001) and overall survival (adjusted hazard ratio, 0.24; 95% confidence interval, 0.11-0.54; P = .001). Patients who were MRD negative had a higher probability of prolonged progression-free survival than patients with detectable residual disease, regardless of treatment group (RVD vs transplant), cytogenetic risk profile, or International Staging System disease stage at diagnosis. These results were similar after completion of maintenance therapy. Our findings confirm the value of MRD status, as determined by NGS, as a prognostic biomarker in multiple myeloma, and suggest that this approach could be used to adapt treatment strategies in future clinical trials.

Serum free light chains, not urine specimens, should be used to evaluate response in light-chain multiple myeloma.

Guidelines for monitoring multiple myeloma (MM) patients expressing light chains only (light-chain MM [LCMM]) rely on measurements of monoclonal protein in urine. Alternatively, serum free light chain (sFLC) measurements have better sensitivity over urine methods, however, demonstration that improved sensitivity provides any clinical benefit is lacking. Here, we compared performance of serum and urine measurements in 113 (72κ, 41λ) newly diagnosed LCMM patients enrolled in the Intergroupe Francophone du Myélome (IFM) 2009 trial. All diagnostic samples (100%) had an abnormal κ:λ sFLC ratio, and involved (monoclonal) FLC (iFLC) expressed at levels deemed measurable for monitoring (≥100 mg/L). By contrast, only 64% patients had measurable levels of monoclonal protein (≥200 mg per 24 hours) in urine protein electrophoresis (UPEP). After 1 and 3 treatment cycles, iFLC remained elevated in 71% and 46% of patients, respectively, whereas UPEP reported a positive result in 37% and 18%; all of the patients with positive UPEP at cycle 3 also had elevated iFLC levels. Importantly, elevated iFLC or an abnormal κ:λ sFLC ratio after 3 treatment cycles associated with poorer progression-free survival (P = .006 and P < .0001, respectively), whereas positive UPEP or urine immunofixation electrophoresis (uIFE) did not. In addition, patients with an abnormal κ:λ sFLC ratio had poorer overall survival (P = .022). Finally, early normalization of κ:λ sFLC ratio but not negative uIFE predicted achieving negative minimal residual disease, as determined by flow cytometry, after consolidation therapy (100% positive predictive value). We conclude that improved sensitivity and prognostic value of serum over urine measurements provide a strong basis for recommending the former for monitoring LCMM patients.

Bortezomib, Doxorubicin, Cyclophosphamide, Dexamethasone Induction Followed by Stem Cell Transplantation for Primary Plasma Cell Leukemia: A Prospective Phase II Study of the Intergroupe Francophone du Myélome.

PURPOSE: Primary plasma cell leukemia (pPCL) is a rare and aggressive malignancy with a poor prognosis. With conventional chemotherapy, patients typically die within 1 year. In all but one of the retrospective studies reported to date, bortezomib and lenalidomide seem to improve survival. We conducted a prospective phase II trial in patients with pPCL to assess the efficacy of an alternate regimen that combines standard chemotherapy, a proteasome inhibitor, and high-dose melphalan and autologous stem cell transplantation (HDM/ASCT) followed by either allogeneic transplantation or bortezomib/lenalidomide maintenance. PATIENTS AND METHODS: Patients 70 years old and younger with newly diagnosed pPCL received four alternating cycles of bortezomib, dexamethasone plus doxorubicin or cyclophosphamide. Peripheral blood stem cells were collected from responding patients with < 1% of circulating plasma cells before HDM/ASCT. As consolidation, young patients received a reduced-intensity conditioning allograft, whereas the remaining patients underwent a second HDM/ASCT followed by 1 year of bortezomib, lenalidomide, dexamethasone. The primary end point was progression-free survival (PFS). RESULTS: Forty patients (median age, 57 years; range, 27 to 71 years) were enrolled. The median follow-up was 28.7 months. In the intention-to-treat analysis, the median PFS and overall survival were 15.1 (95% CI, 8.4; -) and 36.3 (95% CI, 25.6; -) months, respectively. The overall response rate to induction was 69%. One patient underwent a syngeneic allograft and 25 HDM/ASCT (16 of whom subsequently received a reduced-intensity conditioning allograft and seven a second ASCT followed by maintenance). CONCLUSION: In this prospective trial in patients with pPCL, we show that bortezomib, dexamethasone plus doxorubicin or cyclophosphamide induction followed by transplantation induces high response rates and appears to significantly improve PFS.

VTD is superior to VCD prior to intensive therapy in multiple myeloma: results of the prospective IFM2013-04 trial.

The Intergroupe Francophone du Myélome conducted a randomized trial to compare bortezomib-thalidomide-dexamethasone (VTD) with bortezomib-cyclophosphamide-dexamethasone (VCD) as induction before high-dose therapy and autologous stem cell transplantation (ASCT) in patients with newly diagnosed multiple myeloma. Overall, a total of 340 patients were centrally randomly assigned to receive VTD or VCD. After 4 cycles, on an intent-to-treat basis, 66.3% of the patients in the VTD arm achieved at least a very good partial response (primary end point) vs 56.2% in the VCD arm (P = .05). In addition, the overall response rate was significantly higher in the VTD arm (92.3% vs 83.4% in the VCD arm; P = .01). Hematologic toxicity was higher in the VCD arm, with significantly increased rates of grade 3 and 4 anemia, thrombocytopenia, and neutropenia. On the other hand, the rate of peripheral neuropathy (PN) was significantly higher in the VTD arm. With the exception of hematologic adverse events and PN, other grade 3 or 4 toxicities were rare, with no significant differences between the VTD and VCD arms. Our data support the preferential use of VTD rather than VCD in preparation for ASCT. This trial was registered at www.clinicaltrials.gov as #NCT01564537 and at EudraCT as #2013-003174-27.

Outcome of patients with high risk Myelodysplastic Syndrome (MDS) and advanced Chronic Myelomonocytic Leukemia (CMML) treated with decitabine after azacitidine failure.

Outcome of patients with high risk MDS and CMML who failed treatment with azacitidine remains poor with a median survival of 6 months, without established therapy available except allogeneic hematopoietic stem cell transplantation. The objective of our study was to evaluate efficacy of decitabine after azacitidine failure in a relatively large patient cohort based on conflicting results with 0-28% response rates (RR) in this setting in small patient series. Thirty-six consecutive high risk MDS and CMML patients who received decitabine after azacitidine failure were retrospectively reviewed. Response was based on IWG 2006 criteria for MDS and CMML with WBC<13G/l and also included for proliferative CMML the evolution of WBC, splenomegaly (SMG) and extramedullary disease (EMD). Patients received a median number of 3 (range 1-27) cycles of decitabine and 12 patients received at least 6 cycles. Seven (19.4%) patients were responders including 3 marrow CR (mCR), 2 stable disease (SD) with HI-E, 1 SD with HI-N and HI-P and 1 SD with HI-N. In a CMML patient with SD, specific skin lesions resolved with decitabine. Responses were generally short lived (2-5 months) except 1 responder currently ongoing with +11 months follow up. Two non-responders had prolonged SD (without HI) of 21 and 27 months duration respectively. Median OS from onset of decitabine was 7.3 months, without significant difference between responders and non-responders. Treatment with decitabine after azacitidine failure yielded modest ORR (19.4%) with short response duration and poor OS. Thus, use of decitabine in such patients who failed or progressed after azacitidine cannot be recommended, underscoring the need for novel strategies in this setting.

Age is a prognostic factor even among patients with multiple myeloma younger than 66 years treated with high-dose melphalan: the IFM experience on 2316 patients.

Age is a strong prognostic factor in multiple myeloma. The overall survival is shorter in patients older than 66 years, and even shorter in those older than 75 years. Whether age is also a prognostic parameter in patients younger than 66 years treated homogeneously with intensive approaches is unknown. To address this issue, we retrospectively analyzed a series of 2316 patients treated homogeneously with 3-4 cycles of induction chemotherapy followed by a high-dose melphalan course, without any consolidation or maintenance. We show that patients older than 60 years have a statistically significant shorter overall survival. The analysis of prognostic parameters did not show a higher incidence of high-risk cytogenetics, but a higher incidence of International Staging System (ISS) stages 2 and 3, mainly due to higher ß2-microglobulin levels. This study is the first to demonstrate the impact of age in the outcome of 'young' patients with multiple myeloma, and suggests that this parameter should be included in the stratification factors for future prospective clinical trials.

Pomalidomide plus low-dose dexamethasone is active and well tolerated in bortezomib and lenalidomide-refractory multiple myeloma: Intergroupe Francophone du Myélome 2009-02.

The combination of pomalidomide and dexamethasone can be safely administered to patients with multiple myeloma (MM) and has significant efficacy, although the optimal regimen remains to be determined. Patients with MM whose disease progressed after multiple lines of therapy have limited treatment options. We designed a multicenter, phase 2 randomized study assessing two different dose regimens of pomalidomide and dexamethasone in advanced MM. Treatment response was assessed centrally. Pomalidomide (4 mg) was given orally on days 1 to 21 (arm 21/28) or continuously (arm 28/28) over a 28-day cycle, plus dexamethasone given weekly. Eighty-four patients (43, arm 21/28 and 41, arm 28/28) were randomized. The median number of prior lines was 5. Overall response rate was 35% (arm 21/28) and 34% (arm 28/28), independent of the number of prior lines and level of refractoriness. Median duration of response, time to disease progression, and progression-free survival was 7.3, 5.4, and 4.6 months, respectively, which was similar across cohorts. At 23 months follow-up, median overall survival was 14.9 months, with 44% of the patients alive at 18 months. Toxicity consisted primarily of myelosuppression, which was manageable. The efficacy and safety data presented here, along with data from other phase 2 trials, suggest that pomalidomide 4 mg per day on days 1 to 21 of 28 with dexamethasone should be investigated in future trials. This trial is registered at ClinicalTrials.gov (No. NCT01053949).