Pomalidomide, Cyclophosphamide, and Dexamethasone for the Treatment of Relapsed/Refractory Multiple Myeloma: Real-World Analysis of the Pethema-GEM Experience.

INTRODUCTION: Treatment of relapsed/refractory multiple myeloma (RRMM) is highly challenging, especially for patients with disease refractory to initial therapy, and in particular for disease developing refractoriness to lenalidomide. Indeed, with currently approved treatments, median progression-free survival (PFS) in the lenalidomide-refractory setting is less than 10 months, reflecting the difficulty in treating this patient population. Pomalidomide is a second-generation immunomodulatory drug that has shown activity in lenalidomide-refractory disease in the setting of different combinations. PATIENTS AND METHODS: A real-world study was conducted by the Spanish Myeloma group in a cohort of patients with RRMM treated with pomalidomide, cyclophosphamide, and dexamethasone (PomCiDex). One hundred patients were treated with a median of 3 prior lines of therapy. RESULTS: Overall response rate was 39%, with a clinical benefit rate of 93%. Median PFS was 7.6 months; median overall survival (OS) was 12.6 months. Median PFS and OS survival were consistent across the different subgroups analyzed. Prolonged PFS and OS were found in patients with responsive disease. CONCLUSION: Our results compared favorably with those obtained with different pomalidomide-based combinations in a similar patient population. PomCiDex remains a manageable, cost-effective, and all-oral triplet combination for RRMM patients.

Chronic lymphocytic leukemia patients with IGH translocations are characterized by a distinct genetic landscape with prognostic implications.

Chromosome 14q32 rearrangements/translocations involving the immunoglobulin heavy chain (IGH) are rarely detected in chronic lymphocytic leukemia (CLL). The prognostic significance of the IGH translocation is controversial and its mutational profile remains unknown. Here, we present for the first time a comprehensive next-generation sequencing (NGS) analysis of 46 CLL patients with IGH rearrangement (IGHR-CLLs) and we demonstrate that IGHR-CLLs have a distinct mutational profile with recurrent mutations in NOTCH1, IGLL5, POT1, BCL2, FBXW7, ZMYM3, MGA, BRAF and HIST1H1E genes. Interestingly, BCL2 and FBXW7 mutations were significantly associated with this subgroup and almost half of BCL2, IGLL5 and HISTH1E mutations reported were previously identified in non-Hodgkin lymphomas. Notably, IGH/BCL2 rearrangements were associated with a lower mutation frequency and carried BCL2 and IGLL5 mutations, while the other IGHR-CLLs had mutations in genes related to poor prognosis (NOTCH1, SF3B1 and TP53) and shorter time to first treatment (TFT). Moreover, IGHR-CLLs patients showed a shorter TFT than CLL patients carrying 13q-, normal fluorescence in situ hybridization (FISH) and +12 CLL, being this prognosis particularly poor when NOTCH1, SF3B1, TP53, BIRC3 and BRAF were also mutated. The presence of these mutations not only was an independent risk factor within IGHR-CLLs, but also refined the prognosis of low-risk cytogenetic patients (13q-/normal FISH). Hence, our study demonstrates that IGHR-CLLs have a distinct mutational profile from the majority of CLLs and highlights the relevance of incorporating NGS and the status of IGH by FISH analysis to refine the risk-stratification CLL model.

Recovery of polyclonal immunoglobulins one year after autologous stem cell transplantation as a long-term predictor marker of progression and survival in multiple myeloma.

Immunoparesis or suppression of polyclonal immunoglobulins is a very common condition in newly diagnosed myeloma patients. However, the recovery of polyclonal immunoglobulins in the setting of immune reconstitution after autologous stem cell transplantation and its effect on outcome has not yet been explored. We conducted this study in a cohort of 295 patients who had undergone autologous transplantation. In order to explore the potential role of immunoglubulin recovery as a dynamic predictor of progression or survival after transplantation, conditional probabilities of progression-free survival and overall survival were estimated according to immunoglobulin recovery at different time points using a landmark approach. One year after transplant, when B-cell reconstitution is expected to be completed, among 169 patients alive and progression free, 88 patients (52%) showed immunoglobulin recovery and 81 (48%) did not. Interestingly, the group with immunoglobulin recovery had a significantly longer median progression-free survival than the group with persistent immunoparesis (median 60.4 vs. 27.9 months, respectively; Hazard Ratio: 0.45, 95%Confidence Interval: 0.31-0.66; P<0.001), and improved overall survival (11.3 vs. 7.3 years; Hazard Ratio: 0.45, 95%Confidence Interval: 0.27-0.74; P=0.002). Furthermore, the percentage of normal plasma cells detected by flow cytometry in the bone marrow assessed at day 100 after transplantation was associated with the immunoglobulin recovery at that time and may predict immunoglobulin recovery in the subsequent months: nine months and one year. In conclusion, the recovery of polyclonal immunoglobulins one year after autologous transplantation in myeloma patients is an independent long-term predictor marker for progression and survival.

Minimal residual disease evaluation by flow cytometry is a complementary tool to cytogenetics for treatment decisions in acute myeloid leukaemia.

The clinical utility of minimal residual disease (MRD) analysis in acute myeloid leukaemia (AML) is not yet defined. We analysed the prognostic impact of MRD level at complete remision after induction therapy using multiparameter flow cytometry in 306 non-APL AML patients. First, we validated the prognostic value of MRD-thresholds we have previously proposed (≥ 0.1%; ≥ 0.01-0.1%; and <0.01), with a 5-year RFS of 38%, 50% and 71%, respectively (p=0.002). Cytogenetics is the most relevant prognosis factor in AML, however intermediate risk cytogenetics represent a grey zone that require other biomarkers for risk stratification, and we show that MRD evaluation discriminate three prognostic subgroups (p=0.03). Also, MRD assessments yielded relevant information on favourable and adverse cytogenetics, since patients with favourable cytogenetics and high MRD levels have poor prognosis and patients with adverse cytogenetics but undetectable MRD overcomes the adverse prognosis. Interestingly, in patients with intermediate or high MRD levels, intensification with transplant improved the outcome as compared with chemotherapy, while the type of intensification therapy did not influenced the outcome of patients with low MRD levels. Multivariate analysis revealed age, MRD and cytogenetics as independent variables. Moreover, a scoring system, easy in clinical practice, was generated based on MRD level and cytogenetics.

MicroRNA-223 is a novel negative regulator of HSP90B1 in CLL.

BACKGROUND: MicroRNAs are known to inhibit gene expression by binding to the 3'UTR of the target transcript. Downregulation of miR-223 has been recently reported to have prognostic significance in CLL. However, there is no evidence of the pathogenetic mechanism of this miRNA in CLL patients. METHODS: By applying next-generation sequencing techniques we have detected a common polymorphism (rs2307842), in 24% of CLL patients, which disrupts the binding site for miR-223 in HSP90B1 3'UTR. We investigated whether miR-223 directly targets HSP90B1 through luciferase assays and ectopic expression of miR-223. Quantitative real-time polymerase chain reaction and western blot were used to determine HSP90B1 expression in CLL patients. The relationship between rs2307842 status, HSP90B1 expression and clinico-biological data were assessed. RESULTS: HSP90B1 is a direct target for miR-223 by interaction with the putative miR-223 binding site. The analysis in paired samples (CD19+ fraction cell and non-CD19+ fraction cell) showed that the presence of rs2307842 and IGHV unmutated genes determined HSP90B1 overexpression in B lymphocytes from CLL patients. These results were confirmed at the protein level by western blot. Of note, HSP90B1 overexpression was independently predictive of shorter time to the first therapy in CLL patients. By contrast, the presence of rs2307842 was not related to the outcome. CONCLUSIONS: HSP90B1 is a direct target gene of miR-223. Our results provide a plausible explanation of why CLL patients harboring miR-223 downregulation are associated with a poor outcome, pointing out HSP90B1 as a new pathogenic mechanism in CLL and a promising therapeutic target.

Molecular characterization of chronic lymphocytic leukemia patients with a high number of losses in 13q14.

BACKGROUND: Patients with chronic lymphocytic leukemia and 13q deletion as their only FISH abnormality could have a different outcome depending on the number of cells displaying this aberration. Thus, cases with a high number of 13q- cells (13q-H) had both shorter overall survival and time to first therapy. The goal of the study was to analyze the genetic profile of 13q-H patients. DESIGN AND METHODS: A total of 102 samples were studied, 32 of which served as a validation cohort and five were healthy donors. RESULTS: Chronic lymphocytic leukemia patients with higher percentages of 13q- cells (>80%) showed a different level of gene expression as compared to patients with lower percentages (<80%, 13q-L). This deregulation affected genes involved in apoptosis and proliferation (BCR and NFkB signaling), leading to increased proliferation and decreased apoptosis in 13q-H patients. Deregulation of several microRNAs, such as miR-15a, miR-155, miR-29a and miR-223, was also observed in these patients. In addition, our study also suggests that the gene expression pattern of 13q-H cases could be similar to the patients with 11q- or 17p-. CONCLUSIONS: This study provides new evidence regarding the heterogeneity of 13q deletion in chronic lymphocytic leukemia patients, showing that apoptosis, proliferation as well as miRNA regulation are involved in cases with higher percentages of 13q- cells.

BAALC is an important predictor of refractoriness to chemotherapy and poor survival in intermediate-risk acute myeloid leukemia (AML).

We have analyzed brain and acute leukemia, cytoplasmic (BAALC) gene expression and other genetic markers (ERG, EVI1, MN1, PRAME, WT1, FLT3, and NPM1 mutations) in 127 intermediate-risk acute myeloid leukemia (AML) patients: 98 cytogenetically normal and 29 with intermediate-risk cytogenetic alterations. High versus low BAALC expressers showed a higher refractoriness to induction treatment (31% vs 10%; p = .005), lower complete remission rate after salvage therapy (82% vs 97%; p = .010), and lower 3-year overall (23% vs 58%, p < .001) and relapse-free survival (26% vs 52%, p = .006). Similar results were found when cytogenetic subgroups were analyzed separately. Multivariate models confirmed the unfavorable prognosis of this marker. In conclusion, BAALC is a relevant prognostic marker in intermediate-risk AML.

Risk of progression in smouldering myeloma and monoclonal gammopathies of unknown significance: comparative analysis of the evolution of monoclonal component and multiparameter flow cytometry of bone marrow plasma cells.

The present study explored the impact of two novel criteria; having >95% abnormal plasma cells by flow cytometry at diagnosis and the evolving subtype of the disease, as predictors of progression in 61 smouldering multiple myeloma (SMM) and 311 monoclonal gammopathy of unknown significance (MGUS) patients. Although both criteria were of prognostic value, the risk of progression was better identified by immunophenotyping [Hazard Ratio (HR) 6.2 and 17.2 for SMM and MGUS, respectively] than evolving subtype, which had independent prognostic value only in MGUS (HR 3.6). Immunophenotyping discriminated the different risk of progression within the evolving and non-evolving subgroups of SMM (P = 0.01) and MGUS (P < 0.001).

High FOXO3a expression is associated with a poorer prognosis in AML with normal cytogenetics.

The PI3/AKT pathway is up-regulated in acute myeloid leukemia (AML), but its prognostic relevance in cytogenetically normal AML (CN-AML) is unclear. We evaluated RNA levels of AKT and two downstream substrates (FOXO3a-p27) in 110 de novo CN-AML, included in the Spanish PETHEMA therapeutic protocols. Patients with high FOXO3a gene expression displayed shorter OS (p=0.015) and RFS (p=0.048) than low FOXO3a expressers. Features selected in the multivariate analysis as having an independent prognostic value for a shorter survival were WBC>50x10(9)/L, age >65 years and high FOXO3a expression. We concluded that FOXO3a assessment could contribute to improve the molecular-based risk stratification in CN-AML.

Molecular stratification model for prognosis in cytogenetically normal acute myeloid leukemia.

We have evaluated 9 new molecular markers (ERG, EVI1, MLL-PTD, MN1, PRAME, RHAMM, and WT1 gene-expression levels plus FLT3 and NPM1 mutations) in 121 de novo cytogenetically normal acute myeloblastic leukemias. In the multivariate analysis, high ERG or EVI1 and low PRAME expressions were associated with a shorter relapse-free survival (RFS) and overall survival (OS). A 0 to 3 score was given by assigning a value of 0 to favorable parameters (low ERG, low EVI1, and high PRAME) and 1 to adverse parameters. This model distinguished 4 subsets of patients with different OS (2-year OS of 79%, 65%, 46%, and 27%; P = .001) and RFS (2-year RFS of 92%, 65%, 49%, and 43%; P = .005). Furthermore, this score identified patients with different OS (P = .001) and RFS (P = .013), even within the FLT3/NPM1 intermediate-risk/high-risk subgroups. Here we propose a new molecular score for cytogenetically normal acute myeloblastic leukemias, which could improve patient risk-stratification.

A high number of losses in 13q14 chromosome band is associated with a worse outcome and biological differences in patients with B-cell chronic lymphoid leukemia.

BACKGROUND: Among patients with B-cell chronic lymphoid leukemia, those with 13q14 deletion have a favorable outcome. However, whether the percentage of cells with 13q- influences the prognosis or the biological characteristics of this disease is unknown. We analyzed the clinico-biological characteristics and outcome of patients with B-cell chronic lymphoid leukemia with loss of 13q as the sole cytogenetic aberration. DESIGN AND METHODS: Three hundred and fifty patients with B-cell chronic lymphoid leukemia were studied. Clinical data were collected and fluorescence in situ hybridization and molecular studies were carried out. In addition, a gene expression profile was obtained by microarray-based analysis. RESULTS: In 109 out of the 350 cases (31.1%) loss of 13q was the sole cytogenetic aberration at diagnosis. In the subgroup of patients with 80% or more of cells with loss of 13q (18 cases), the overall survival was 56 months compared with not reached in the 91 cases in whom less than 80% of cells had loss of 13q (p< 0.0001). The variables included in the multivariate analysis for overall survival were the percentage of losses of 13q14 (p=0.001) and B symptoms (p=0.007). The time to first therapy in the group with 80% or more vs. less than 80% of losses was 38 months vs. 87 months, respectively (p=0.05). In the multivariate analysis the variables selected were unmutated status of IgV(H) (p=0.001) and a high level of beta(2)microglobulin (p=0.003). Interestingly, these differences regarding overall survival and time to first therapy were also present when other cut-offs were considered. The gene expression profile of patients with a high number of losses in 13q14 showed a high proliferation rate, downregulation of apoptosis-related genes, and dysregulation of genes related to mitochondrial functions. CONCLUSIONS: Patients with B-cell chronic lymphoid leukemia with a high number of losses in 13q14 as the sole cytogenetic aberration at diagnosis display different clinical and biological features: short overall survival and time to first therapy as well as more proliferation and less apoptosis. A quantification of the number of cells showing a genetic abnormality should, therefore, be included in the study of the prognostic factors of B-cell chronic lymphoid leukemia.

New criteria to identify risk of progression in monoclonal gammopathy of uncertain significance and smoldering multiple myeloma based on multiparameter flow cytometry analysis of bone marrow plasma cells.

Monoclonal gammopathy of uncertain significance (MGUS) and smoldering multiple myeloma (SMM) are plasma cell disorders with a risk of progression of approximately 1% and 10% per year, respectively. We have previously shown that the proportion of bone marrow (BM) aberrant plasma cells (aPCs) within the BMPC compartment (aPC/BMPC) as assessed by flow cytometry (FC) contributes to differential diagnosis between MGUS and multiple myloma (MM). The goal of the present study was to investigate this parameter as a marker for risk of progression in MGUS (n = 407) and SMM (n = 93). Patients with a marked predominance of aPCs/BMPC (> or = 95%) at diagnosis displayed a significantly higher risk of progression both in MGUS and SMM (P< .001). Multivariate analysis for progression-free survival (PFS) selected the percentage aPC/BMPC (> or = 95%) as the most important independent variable, together with DNA aneuploidy and immunoparesis, for MGUS and SMM, respectively. Using these independent variables, we have identified 3 risk categories in MGUS (PFS at 5 years of 2%, 10%, and 46%, respectively; P< .001) and SMM patients (PFS at 5 years of 4%, 46%, and 72%, respectively; P < .001). Our results show that multiparameter FC evaluation of BMPC at diagnosis is a valuable tool that could help to individualize the follow-up strategy for MGUS and SMM patients.