Predictors of unsustained measurable residual disease negativity in transplant-eligible patients with multiple myeloma.

ABSTRACT: The role of measurable residual disease (MRD) negativity as a biomarker to stop treatment is being investigated in transplant-eligible patients with multiple myeloma (MM). Thus, it is important to identify risk factors of MRD resurgence and/or progressive disease (PD) among patients achieving undetectable MRD to avoid undertreating them. Here, we studied 267 newly diagnosed transplant-eligible patients with MM enrolled in the GEM2012MENOS65 and GEM2014MAIN clinical trials who achieved MRD negativity by next-generation flow cytometry. After a median follow-up of 73 months since the first MRD negative assessment, 111 of the 267 (42%) patients showed MRD resurgence and/or PD. The only prognostic factors at diagnosis that predicted MRD resurgence and/or PD were an International Staging System (ISS) 3 and the presence of ≥0.01% circulating tumor cells (CTCs). Failure to achieve MRD negativity after induction also predicted higher risk of MRD resurgence and/or PD. Patients having 0 vs 1 vs ≥2 risk factors (ISS 3, ≥0.01% CTCs, and late MRD negativity) showed 5-year rates of MRD resurgence and/or PD of 16%, 33%, and 57%, respectively (P < .001). Thus, these easily measurable risk factors could help refine the selection of patients for whom treatment cessation after MRD negativity is being investigated in clinical trials. This trial was registered at www.clinicaltrials.gov as NCT01916252 and NCT02406144.

Measurable Residual Disease by Mass Spectrometry and Next-Generation Flow to Assess Treatment Response in Myeloma.

Quantitative immuneprecipitation mass-spectrometry (QIP-MS) allows the identification of the M-protein in patients with multiple myeloma (MM) otherwise in complete response, and could be considered suitable for measurable residual disease (MRD) evaluation in peripheral blood. In the context of the GEM2012MENOS65 and GEM2014MAIN trials, we compared the performance of QIP-MS in serum with next-generation flow (NGF) cytometry in bone marrow to assess MRD in paired samples obtained post-induction, transplant, consolidation and after 24 cycles of maintenance. At each time point, both NGF and QIP-MS were able to segregate two groups of patients with significantly different progression-free survival (PFS); when the evolution of the results obtained with either method was considered, maintaining or converting to MRD negativity was associated with longer survival, significantly better when compared to sustaining or converting to MRD positivity. Of note, reemergence of MRD by QIP-MS was associated with high risk of imminent clinical progression. In conclusion, MRD evaluation by NGF and MS achieve similar prognostic value based in single time point assessments and kinetics. Thus, the minimally-invasive nature of MRD monitoring by MS represents a breakthrough in high-sensitive response assessment in MM. GEM2012MENOS65: #NCT01916252 and EudraCT as #2012-005683-10. GEM2014MAIN: #NCT02406144 and at EudraCT as 2014-00055410.

Lenalidomide and dexamethasone maintenance with or without ixazomib, tailored by residual disease status in myeloma.

From November 2014 to May 2017, 332 patients homogeneously treated with bortezomib, lenalidomide, and dexamethasone (VRD) induction, autologous stem cell transplant, and VRD consolidation were randomly assigned to receive maintenance therapy with lenalidomide and dexamethasone (RD; 161 patients) vs RD plus ixazomib (IRD; 171 patients). RD consisted of lenalidomide 15 mg/d from days 1 to 21 plus dexamethasone 20 mg/d on days 1 to 4 and 9 to 12 at 4-week intervals, whereas in the IRD arm, oral ixazomib at a dose of 4 mg on days 1, 8, and 15 was added. Therapy for patients with negative measurable residual disease (MRD) after 24 cycles was discontinued, whereas those who tested positive for MRD remained on maintenance with RD for 36 more cycles. After a median follow-up of 69 months from the initiation of maintenance, the progression-free survival (PFS) was similar in both arms, with a 6-year PFS rate of 61.3% and 55.6% for RD and IRD, respectively (hazard ratio, 1.136; 95% confidence interval, 0.809-1.603). After 2 years of maintenance, treatment was discontinued in 163 patients with negative MRD, whereas 63 patients with positive MRD continued with RD therapy. Maintenance discontinuation in patients tested negative for MRD resulted in a low progression rate (17.2% at 4 years), even in patients with high-risk features. In summary, our results show the efficacy of RD maintenance and support the safety of maintenance therapy discontinuation in patients with negative MRD at 2 years. This trial was registered at www.clinicaltrials.gov as #NCT02406144 and at EudraCT as 2014-00055410.

Single-point and kinetics of peripheral residual disease by mass spectrometry to predict outcome in patients with high risk smoldering multiple myeloma included in the GEM-CESAR trial.

The value of quantitative immunoprecipitation mass spectrometry (QIP-MS) to identify the M-protein is being investigated in patients with monoclonal gammopathies but no data are yet available in high-risk smoldering myeloma (HRsMM). We have therefore investigated QIP-MS to monitor peripheral residual disease (PRD) in 62 HRsMM patients enrolled in the GEM-CESAR trial. After 24 cycles of maintenance, detecting the M-protein by MS or clonal plasma cells by NGF identified cases with a significantly shorter median PFS (mPFS; MS: not reached vs 1,4 years, p=0.001; NGF: not reached vs 2 years, p=0.0002) but reaching CR+sCR did not discriminate patients with different outcome. With NGF as a reference, the combined results of NGF and MS showed a high negative predictive value (NPV) of MS: 81% overall and 73% at treatment completion. When sequential results were considered, sustained negativity by MS or NGF was associated with a very favorable outcome with a mPFS not yet reached vs 1.66 years and 2.18 years in cases never attaining PRD or minimal residual disease (MRD) negativity, respectively. We can thus conclude that 1) the standard response categories of the IMWG do not seem to be useful for treatment monitoring in HRsMM patients, 2) MS could be used as a non-invasive, clinical valuable tool with the capacity of guiding timely bone marrow evaluations (based on its high NPV with NGF as a reference) and 3) similarly to NGF, sequential results of MS are able identify a subgroup of HRsMM patients with long-term disease control. This study was registered at www.clinicaltrials.gov (ClinicalTrials.gov identifier: NCT02415413).

Immunoparesis recovery in newly diagnosed transplant ineligible multiple myeloma patients, an independent prognostic factor that complements minimal residual disease.

Information on the prognostic value of immunoparesis (IP) recovery in multiple myeloma (MM) patients has been only generated in some observational and retrospective studies. We have evaluated the prognostic impact of IP recovery and its association with minimal residual disease (MRD) in a series of 113 newly diagnosed transplant-ineligible (NDTI) patients, that received fix duration treatment (18 cycles of VMP/lenalidomide-dexamethasone) within the PETHEMA/GEM2010MAS65 trial and who achieved CR or VGPR. Immunoglobulin levels were measured at diagnosis, at the end of treatment (after cycle 18th) and during subsequent follow up whereas MRD was analyzed only at the end of the treatment (after cycle 18th). We found that patients who had IP at diagnosis and recovered it during or after treatment had longer progression free survival (PFS) [p < 0.001; HR 0.32 (0.19-0.52)] and longer overall survival (OS) [p = 0.007; HR 0.40 (0.20-0.80)] compared to those who failed to recover it. When we analyzed IP recovery in MRD negative patients, we found that those cases with IP recovery had longer PFS [p = 0.007; HR 0.31 (0.13-0.76)] and longer OS [p = 0.012; HR 0.21 (0.06-0.80)] as compared to MRD negative patients but without IP recovery. In conclusion, IP recovery confers better prognosis in NDTI-MM patients with fixed duration treatment who achieve CR or VGPR and the prognostic value of MRD can be complemented when combined with IP recovery.

Tumor cells in light-chain amyloidosis and myeloma show distinct transcriptional rewiring of normal plasma cell development.

Although light-chain amyloidosis (AL) and multiple myeloma (MM) are characterized by tumor plasma cell (PC) expansion in bone marrow (BM), their clinical presentation differs. Previous attempts to identify unique pathogenic mechanisms behind such differences were unsuccessful, and no studies have investigated the differentiation stage of tumor PCs in patients with AL and MM. We sought to define a transcriptional atlas of normal PC development in secondary lymphoid organs (SLOs), peripheral blood (PB), and BM for comparison with the transcriptional programs (TPs) of tumor PCs in AL, MM, and monoclonal gammopathy of undetermined significance (MGUS). Based on bulk and single-cell RNA sequencing, we observed 13 TPs during transition of normal PCs throughout SLOs, PB, and BM. We further noted the following: CD39 outperforms CD19 to discriminate newborn from long-lived BM-PCs; tumor PCs expressed the most advantageous TPs of normal PC differentiation; AL shares greater similarity to SLO-PCs whereas MM is transcriptionally closer to PB-PCs and newborn BM-PCs; patients with AL and MM enriched in immature TPs had inferior survival; and protein N-linked glycosylation-related TPs are upregulated in AL. Collectively, we provide a novel resource to understand normal PC development and the transcriptional reorganization of AL and other monoclonal gammopathies.

Deep MRD profiling defines outcome and unveils different modes of treatment resistance in standard- and high-risk myeloma.

Patients with multiple myeloma (MM) carrying standard- or high-risk cytogenetic abnormalities (CAs) achieve similar complete response (CR) rates, but the later have inferior progression-free survival (PFS). This questions the legitimacy of CR as a treatment endpoint and represents a biological conundrum regarding the nature of tumor reservoirs that persist after therapy in high-risk MM. We used next-generation flow (NGF) cytometry to evaluate measurable residual disease (MRD) in MM patients with standard- vs high-risk CAs (n = 300 and 90, respectively) enrolled in the PETHEMA/GEM2012MENOS65 trial, and to identify mechanisms that determine MRD resistance in both patient subgroups (n = 40). The 36-month PFS rates were higher than 90% in patients with standard- or high-risk CAs achieving undetectable MRD. Persistent MRD resulted in a median PFS of âˆ¼3 and 2 years in patients with standard- and high-risk CAs, respectively. Further use of NGF to isolate MRD, followed by whole-exome sequencing of paired diagnostic and MRD tumor cells, revealed greater clonal selection in patients with standard-risk CAs, higher genomic instability with acquisition of new mutations in high-risk MM, and no unifying genetic event driving MRD resistance. Conversely, RNA sequencing of diagnostic and MRD tumor cells uncovered the selection of MRD clones with singular transcriptional programs and reactive oxygen species-mediated MRD resistance in high-risk MM. Our study supports undetectable MRD as a treatment endpoint for patients with MM who have high-risk CAs and proposes characterizing MRD clones to understand and overcome MRD resistance. This trial is registered at www.clinicaltrials.gov as #NCT01916252.

Recovery of uninvolved heavy/light chain pair immunoparesis in newly diagnosed transplant-eligible myeloma patients complements the prognostic value of minimal residual disease detection.

Immunoparesis (IP) in multiple myeloma (MM) patients can be measured by classic assessment of immunoglobulin (Ig) levels or by analysis of the uninvolved heavy/light chain pair of the same immunoglobulin (uHLC) by the Hevylite® assay. In this study we evaluate the prognostic value of recovery from IP measured by classic total Ig and uHLC assessment in newly diagnosed MM transplant-eligible (NDMM-TE) patients with intensive treatment and its association with Minimal Residual Disease (MRD). Patients were enrolled and treated in the PETHEMA/GEM2012MENOS65 trial and continued in the PETHEMA/GEM2014MAIN trial. Total Ig (IgG, IgA and IgM) and uHLC were analyzed in a central laboratory at diagnosis, after consolidation treatment and after the first year of maintenance. MRD was analyzed by next generation flow cytometry after consolidation (sensitivity level 2x10-6). We found no differences in progression free survival (PFS) between patients who recovered and patients who didn't recover from IP after consolidation when examining classic total Ig and uHLC. However, after the first year of maintenance, in contrast to patients with classic IP, patients with recovery from uHLC IP had longer PFS than patients without recovery, with hazard ratio of 0.42 (CI95% 0.21-0.81; p=0.008). Multivariate analysis with Cox proportional-hazards regression models confirmed recovery from uHLC IP after the first year of maintenance as an independent prognostic factor for PFS, with an increase in C-statistic of 0.05 (-0.04-0.14; p<0.001) when adding uHLC IP recovery. Moreover, we observed that MRD status and uHLC IP recovery affords complementary information for risk stratification. In conclusion, recovery from uHLC IP after one year of maintenance is an independent prognostic factor for PFS in NDMM-TE patients who receive intensive treatment. Immune reconstitution, measured as recovery from uHLC IP, provides complementary prognostic information to MRD assessment.

Biological and clinical significance of dysplastic hematopoiesis in patients with newly diagnosed multiple myeloma.

Risk of developing myelodysplastic syndrome (MDS) is significantly increased in both multiple myeloma (MM) and monoclonal gammopathy of undetermined significance, suggesting that it is therapy independent. However, the incidence and sequelae of dysplastic hematopoiesis at diagnosis are unknown. Here, we used multidimensional flow cytometry (MFC) to prospectively screen for the presence of MDS-associated phenotypic alterations (MDS-PA) in the bone marrow of 285 patients with MM enrolled in the PETHEMA/GEM2012MENOS65 trial (#NCT01916252). We investigated the clinical significance of monocytic MDS-PA in a larger series of 1252 patients enrolled in 4 PETHEMA/GEM protocols. At diagnosis, 33 (11.6%) of 285 cases displayed MDS-PA. Bulk and single-cell-targeted sequencing of MDS recurrently mutated genes in CD34+ progenitors (and dysplastic lineages) from 67 patients revealed clonal hematopoiesis in 13 (50%) of 26 cases with MDS-PA vs 9 (22%) of 41 without MDS-PA; TET2 and NRAS were the most frequently mutated genes. Dynamics of MDS-PA at diagnosis and after autologous transplant were evaluated in 86 of 285 patients and showed that in most cases (69 of 86 [80%]), MDS-PA either persisted or remained absent in patients with or without MDS-PA at diagnosis, respectively. Noteworthy, MDS-associated mutations infrequently emerged after high-dose therapy. Based on MFC profiling, patients with MDS-PA have altered hematopoiesis and T regulatory cell distribution in the tumor microenvironment. Importantly, the presence of monocytic MDS-PA at diagnosis anticipated greater risk of hematologic toxicity and was independently associated with inferior progression-free survival (hazard ratio, 1.5; P = .02) and overall survival (hazard ratio, 1.7; P = .01). This study reveals the biological and clinical significance of dysplastic hematopoiesis in newly diagnosed MM, which can be screened with moderate sensitivity using cost-effective MFC.

Role of urine immunofixation in the complete response assessment of MM patients other than light-chain-only disease.

Response criteria for multiple myeloma (MM) require monoclonal protein (M-protein)-negative status on both serum immunofixation electrophoresis (sIFE) and urine (uIFE) immunofixation electrophoresis for classification of complete response (CR). However, uIFE is not always performed for sIFE-negative patients. We analyzed M-protein evaluations from 384 MM patients (excluding those with light-chain-only disease) treated in the GEM2012MENOS65 (NCT01916252) trial to determine the uIFE-positive rate in patients who became sIFE-negative posttreatment and evaluate rates of minimal residual disease (MRD)-negative status and progression-free survival (PFS) among patients achieving CR, CR but without uIFE available (uncertain CR; uCR), or very good partial response (VGPR). Among 107 patients with M-protein exclusively in serum at diagnosis who became sIFE-negative posttreatment and who had uIFE available, the uIFE-positive rate was 0%. Among 161 patients with M-protein in both serum and urine at diagnosis who became sIFE-negative posttreatment, 3 (1.8%) were uIFE positive. Among patients achieving CR vs uCR, there were no significant differences in postconsolidation MRD-negative (<10-6; 76% vs 75%; P = .9) and 2-year PFS (85% vs 88%; P = .4) rates; rates were significantly lower among patients achieving VGPR. Our results suggest that uIFE is not necessary for defining CR in MM patients other than those with light-chain-only disease.

Bortezomib, lenalidomide, and dexamethasone as induction therapy prior to autologous transplant in multiple myeloma.

Achieving and maintaining a high-quality response is the treatment goal for patients with newly diagnosed multiple myeloma (NDMM). The phase 3 PETHEMA/GEM2012 study, in 458 patients aged ≤65 years with NDMM, is evaluating bortezomib (subcutaneous) + lenalidomide + dexamethasone (VRD) for 6 cycles followed by autologous stem cell transplant (ASCT) conditioned with IV busulfan + melphalan vs melphalan and posttransplant consolidation with 2 cycles of VRD. We present grouped response analysis of induction, transplant, and consolidation. Responses deepened over time; in patients who initiated cycle 6 of induction (n = 426), the rates of a very good partial response or better were 55.6% by cycle 3, 63.8% by cycle 4, 68.3% by cycle 5, and 70.4% after induction. The complete response rate of 33.4% after induction in the intent-to-treat (ITT) population, which was similar in the 92 patients with high-risk cytogenetics (34.8%), also deepened with further treatment (44.1% after ASCT and 50.2% after consolidation). Rates of undetectable minimal residual disease (median 3 × 10-6 sensitivity) in the ITT population also increased from induction (28.8%) to transplant (42.1%) and consolidation (45.2%). The most common grade ≥3 treatment-emergent adverse events during induction were neutropenia (12.9%) and infection (9.2%). Grade ≥2 peripheral neuropathy (grouped term) during induction was 17.0%, with a low frequency of grade 3 (3.7%) and grade 4 (0.2%) events. VRD is an effective and well-tolerated regimen for induction in NDMM with deepening response throughout induction and over the course of treatment. This trial was registered at www.clinicaltrials.gov as #NCT01916252 and EudraCT as #2012-005683-10.

Potential Survival Benefit for Patients Receiving Allogeneic Hematopoietic Stem Cell Transplantation after Nivolumab Therapy for Relapse/Refractory Hodgkin Lymphoma: Real-Life Experience in Spain.

Clinical trials have shown that nivolumab has remarkable activity against relapsed/refractory classical Hodgkin lymphoma (cHL). However, the role of allogeneic hematopoietic stem cell transplantation (allo-HSCT) as consolidation therapy in these patients remains controversial. We performed a retrospective analysis of data from 74 patients treated with nivolumab. The overall response rate was 58% (including 30.6% with complete responses). Treatment-related adverse events were reported in 56.8% of patients (grade ≥3 in 9.4%). The main reasons for nivolumab discontinuation were referral for transplantation (41.7% patients) and disease progression (37.5%). The 2-year overall survival (OS) rate was 52% for the entire series. Ultimately, 39 patients underwent allo-HSCT. The cumulative incidence of grade II-IV acute graft-versus-host disease was 33.3% (grade III-IV in 2 patients). The cumulative incidence of nonrelapse mortality was 13.2%. Among the patients who responded to nivolumab, the 2-year OS and progression-free survival (PFS) were higher in patients who underwent consolidation with allo-HSCT (77.5% versus 42.6% [P = .126] and 73.9% versus 27.2% [P = .025], respectively). Thus, the efficacy and safety of nivolumab were comparable to values reported in previous clinical trials. The percentage of patients who bridged to transplantation was high, indicating a preference for Spanish physicians. These results suggest that consolidation allo-HSCT increases OS and PFS.

Bendamustine as part of conditioning of autologous stem cell transplantation in patients with aggressive lymphoma: a phase 2 study from the GELTAMO group.

We conducted a phase 2 trial to evaluate the safety and efficacy of bendamustine instead of BCNU (carmustine) in the BEAM (BCNU, etoposide, cytarabine and melphalan) regimen (BendaEAM) as conditioning for autologous stem-cell transplantation (ASCT) in patients with aggressive lymphomas. The primary endpoint was 3-year progression-free survival (PFS). Sixty patients (median age 55 [28-71] years) were included. All patients (except one who died early) engrafted after a median of 11 (9-72) and 14 (4-53) days to achieve neutrophil and platelet counts of >0.5 × 109 /l and >20 × 109 /l, respectively. Non-relapse mortality at 100 days and 1 year were 3.3% and 6.7%, respectively. With a median follow-up of 67 (40-77) months, the estimated 3-year PFS and overall survival (OS) were 58% and 75%, respectively. Patients in partial response at study entry had significantly worse PFS and OS than patients who underwent ASCT in complete metabolic remission, and this was the only prognostic factor associated with both PFS (Relative risk [RR], 0.27 [95% confidence interval {CI} [0.12-0.56]) and OS (RR, 0.40 [95% CI 0.17-0.97]) in the multivariate analysis. BendaEAM conditioning is therefore a feasible and effective regimen in patients with aggressive lymphomas. However, patients not in complete metabolic remission at the time of transplant had poorer survival and so should be considered for alternative treatment strategies.

Phenotypic, transcriptomic, and genomic features of clonal plasma cells in light-chain amyloidosis.

Immunoglobulin light-chain amyloidosis (AL) and multiple myeloma (MM) are 2 distinct monoclonal gammopathies that involve the same cellular compartment: clonal plasma cells (PCs). Despite the fact that knowledge about MM PC biology has significantly increased in the last decade, the same does not apply for AL. Here, we used an integrative phenotypic, molecular, and genomic approach to study clonal PCs from 24 newly diagnosed patients with AL. Through principal-component-analysis, we demonstrated highly overlapping phenotypic profiles between AL and both monoclonal gammopathy of undetermined significance and MM PCs. However, in contrast to MM, highly purified fluorescence-activated cell-sorted clonal PCs from AL (n = 9) showed almost normal transcriptome, with only 38 deregulated genes vs normal PCs; these included a few tumor-suppressor (CDH1, RCAN) and proapoptotic (GLIPR1, FAS) genes. Notwithstanding, clonal PCs in AL (n = 11) were genomically unstable, with a median of 9 copy number alterations (CNAs) per case, many of such CNAs being similar to those found in MM. Whole-exome sequencing (WES) performed in 5 AL patients revealed a median of 15 nonrecurrent mutations per case. Altogether, our results show that in the absence of a unifying mutation by WES, clonal PCs in AL display phenotypic and CNA profiles similar to MM, but their transcriptome is remarkably similar to that of normal PCs.

Phenotypic and genomic analysis of multiple myeloma minimal residual disease tumor cells: a new model to understand chemoresistance.

Persistence of chemoresistant minimal residual disease (MRD) plasma cells (PCs) is associated with inferior survival in multiple myeloma (MM). Thus, characterization of the minor MRD subclone may represent a unique model to understand chemoresistance, but to our knowledge, the phenotypic and genetic features of the MRD subclone have never been investigated. Here, we compared the antigenic profile of MRD vs diagnostic clonal PCs in 40 elderly MM patients enrolled in the GEM2010MAS65 study and showed that the MRD subclone is enriched in cells overexpressing integrins (CD11a/CD11c/CD29/CD49d/CD49e), chemokine receptors (CXCR4), and adhesion molecules (CD44/CD54). Genetic profiling of MRD vs diagnostic PCs was performed in 12 patients; 3 of them showed identical copy number alterations (CNAs), in another 3 cases, MRD clonal PCs displayed all genetic alterations detected at diagnosis plus additional CNAs that emerged at the MRD stage, whereas in the remaining 6 patients, there were CNAs present at diagnosis that were undetectable in MRD clonal PCs, but also a selected number of genetic alterations that became apparent only at the MRD stage. The MRD subclone showed significant downregulation of genes related to protein processing in endoplasmic reticulum, as well as novel deregulated genes such as ALCAM that is prognostically relevant in MM and may identify chemoresistant PCs in vitro. Altogether, our results suggest that therapy-induced clonal selection could be already present at the MRD stage, where chemoresistant PCs show a singular phenotypic signature that may result from the persistence of clones with different genetic and gene expression profiles. This trial was registered atwww.clinicaltrials.gov as #NCT01237249.

Autologous Stem Cell Transplantation for Follicular Lymphoma: Favorable Long-Term Survival Irrespective of Pretransplantation Rituximab Exposure.

High-dose chemotherapy supported by autologous stem cell transplantation (HDT/ASCT) has contributed to modify the natural history of follicular lymphoma (FL); however, an overall survival (OS) benefit has been demonstrated at relapse only after a rituximab-free chemotherapy regimen. A total of 655 patients with FL were reported to the Spanish GELTAMO (Grupo Español de Linfomas y Trasplantes de Médula Ósea) registry and underwent first ASCT between 1989 and 2007. A total of 203 patients underwent ASCT in first complete response (CR1), 174 in second complete response (CR2), 28 in third complete response (CR3), 140 in first partial response (PR1), 81 in subsequent PR, and 29 with resistant/refractory disease; 184 patients received rituximab before ASCT. With a median follow-up of 12 years from ASCT, median progression-free survival (PFS) and overall survival (OS) were 9.7 and 21.3 years, respectively. Actuarial 12-year PFS and OS were 63% (95% confidence interval [CI], 58%-68%) and 73% (95% CI, 68%-78%), respectively, for patients in CR (with a plateau in the curve beyond 15.9 years), 25% (95% CI, 19%-28%) and 49% (95% CI 42%-56%), respectively, for patients in PR, and 23% (95% CI, 8%-48%) and 28% (95% CI, 9%-45%), respectively, for patients with resistant/refractory disease (P < .001). In patients who received rituximab before ASCT, the estimated 9-year PFS and OS from ASCT were 59.5% (95% CI, 51%-67%) and 75% (95% CI, 68%-83%), respectively. Interestingly, for patients who underwent transplantation in CR ≥2 or PR ≥2 who had received rituximab before ASCT (n = 90), 9-year PFS and OS were 61% (95% CI, 51%-73%) and 75% (95% CI, 65%-80%), respectively, with no relapses occurring beyond 5.1 years after ASCT. The cumulative incidence of second malignancies in the global series was 6.7% at 5 years and 12.8% at 10 years. This analysis strongly suggests that ASCT is a potentially curative option for eligible patients with FL. In the setting of relapse, it is of especial interest in pretransplantation rituximab-sensitive patients with FL.

Critical analysis of the stringent complete response in multiple myeloma: contribution of sFLC and bone marrow clonality.

Stringent complete response (sCR) criteria are used in multiple myeloma as a deeper response category compared with CR, but prospective validation is lacking, it is not always clear how evaluation of clonality is performed, and is it not known what the relative clinical influence is of the serum free light chain ratio (sFLCr) and bone marrow (BM) clonality to define more sCR. To clarify this controversy, we focused on 94 patients that reached CR, of which 69 (73%) also fulfilled the sCR criteria. Patients with sCR displayed slightly longer time to progression (median, 62 vs 53 months, respectively; P = .31). On analyzing this contribution to the prognosis of sFLCr or clonality, it was found that the sFLCr does not identify patients in CR at distinct risk; by contrast, low-sensitive multiparametric flow cytometry (MFC) immunophenotyping (2 colors), which is equivalent to immunohistochemistry, identifies a small number of patients (5 cases) with high residual tumor burden and dismal outcome; nevertheless, using traditional 4-color MFC, persistent clonal BM disease was detectable in 36% of patients, who, compared with minimal residual disease-negative cases, had a significantly inferior outcome. These results show that the current definition of sCR should be revised.

Lenalidomide plus dexamethasone versus observation in patients with high-risk smouldering multiple myeloma (QuiRedex): long-term follow-up of a randomised, controlled, phase 3 trial.

BACKGROUND: The standard of care for smouldering multiple myeloma is observation. We did the QuiRedex study to compare early treatment with lenalidomide plus dexamethasone with observation in patients with high-risk smouldering multiple myeloma. Here we report the long-term follow-up results of the trial. METHODS: We did this open-label, randomised, controlled phase 3 study at 19 centres in Spain and three centres in Portugal. Patients aged 18 years or older with high-risk smouldering multiple myeloma were randomly assigned (1:1), via a computerised random number generator, to receive either early treatment with lenalidomide plus dexamethasone or observation, with dynamic balancing to maintain treatment balance within the two groups. Randomisation was stratified by time from diagnosis of smouldering multiple myeloma to study enrolment (≤6 months vs >6 months). Patients in the treatment group received nine 4-week induction cycles (lenalidomide 25 mg per day on days 1-21, plus dexamethasone 20 mg per day on days-1-4 and days 12-15), followed by maintenance therapy (lenalidomide 10 mg per day on days 1-21 of each 28-day cycle) up to 2 years. Group allocation was not masked from study investigators or patients. The primary endpoint was time from randomisation to progression to symptomatic myeloma. The primary analysis was based on the per-protocol population, restricted to patients who fulfilled the protocol in terms of eligibility. Safety assessments were based on the intention-to-treat population. This trial is registered with ClinicalTrials.gov, number NCT00480363. FINDINGS: Between Nov 8, 2007, and June 9, 2010, 125 patients were enrolled and underwent randomisation. 119 patients comprised the per-protocol population and were randomly assigned to receive either lenalidomide plus dexamethasone (n=57) or observation (n=62). The cutoff date for this update was June 30, 2015. Median follow-up for surviving patients was 75 months (IQR 67-85). Lenalidomide plus dexamethasone continued to provide a benefit on time to progression compared with observation (median time to progression not reached [95% CI 47 months-not reached] vs 23 months [16-31]; hazard ratio [HR] 0·24 [95% CI 0·14-0·41]; p<0·0001). Progression to multiple myeloma occurred in 53 (86%) of 62 patients in the observation group compared with 22 (39%) of 57 patients in the treatment group. At data cutoff, ten (18%) patients had died in the treatment group and 22 (36%) patients had died in the observation group; median overall survival from the time of study entry had not been reached in either group (95% CI 65 months-not reached vs 53 months-not reached; HR 0·43 [95% CI 0·21-0·92], p=0·024). Survival in patients who had received subsequent treatments at the time of progression to active disease did not differ between groups (HR 1·34 [95% CI 0·54-3·30]; p=0·50). The most frequently reported grade 3 adverse events in patients given lenalidomide plus dexamethasone were infection (four [6%]), asthenia (four [6%]), neutropenia (three [5%]), and skin rash (two [3%]); these events all occurred during induction therapy. No grade 4 adverse events occurred, but one (2%) patient in the lenalidomide plus dexamethasone group died from a respiratory infection during induction therapy The frequency of second primary malignancies was higher in patients in the treatment group than in those in the observation group (six [10%] of 62 patients vs one [2%] of 63 patients), but the cumulative risk of development did not differ significantly between the groups (p=0·070). INTERPRETATION: This study is, to our knowledge, the first randomised trial in which early treatment has been assessed in selected patients with high-risk smouldering multiple myeloma. Positive results from ongoing trials would support the use of early treatment for patients with high-risk disease in the near future. FUNDING: Pethema (Spanish Program for the Treatment of Hematologic Diseases).

Lenalidomide plus dexamethasone for high-risk smoldering multiple myeloma.

BACKGROUND: For patients with smoldering multiple myeloma, the standard of care is observation until symptoms develop. However, this approach does not identify high-risk patients who may benefit from early intervention. METHODS: In this randomized, open-label, phase 3 trial, we randomly assigned 119 patients with high-risk smoldering myeloma to treatment or observation. Patients in the treatment group received an induction regimen (lenalidomide at a dose of 25 mg per day on days 1 to 21, plus dexamethasone at a dose of 20 mg per day on days 1 to 4 and days 12 to 15, at 4-week intervals for nine cycles), followed by a maintenance regimen (lenalidomide at a dose of 10 mg per day on days 1 to 21 of each 28-day cycle for 2 years). The primary end point was time to progression to symptomatic disease. Secondary end points were response rate, overall survival, and safety. RESULTS: After a median follow-up of 40 months, the median time to progression was significantly longer in the treatment group than in the observation group (median not reached vs. 21 months; hazard ratio for progression, 0.18; 95% confidence interval [CI], 0.09 to 0.32; P<0.001). The 3-year survival rate was also higher in the treatment group (94% vs. 80%; hazard ratio for death, 0.31; 95% CI, 0.10 to 0.91; P=0.03). A partial response or better was achieved in 79% of patients in the treatment group after the induction phase and in 90% during the maintenance phase. Toxic effects were mainly grade 2 or lower. CONCLUSIONS: Early treatment for patients with high-risk smoldering myeloma delays progression to active disease and increases overall survival. (Funded by Celgene; ClinicalTrials.gov number, NCT00480363.).