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Patients with multiple myeloma are generally older and vary in fitness levels, which may influence the clinical benefit of treatment. Patients from the large, phase 3 FIRST trial in newly diagnosed multiple myeloma (NDMM) were retrospectively investigated to determine outcomes based on frailty using scores for age, Charlson Comorbidity Index (CCI), and Eastern Cooperative Oncology Group performance status (ECOG PS), instead of the EQ-5D quality-of-life questionnaire, as previously reported. ECOG PS (n = 1618) was investigated in frailty groups: frail (49%) and nonfrail (51%). Frail patients experienced worse progression-free and overall survival vs nonfrail patients. Prognostic assessment was improved when combining frailty and International Staging System stage (I/II vs III). Frail patients had a higher risk of developing grade 3/4 treatment-emergent adverse events. Treatment effects observed in the FIRST trial were confirmed per frailty group and per frailty and ISS group. The use of this ECOG PS-containing frailty scale as a predictive measure of clinical outcomes in patients with transplant-ineligible NDMM is supported by data from the FIRST trial. This score, based on age, CCI, and ECOG PS, can be easily replicated and may help design future myeloma studies in frail or nonfrail elderly patients.

The most recent update to the International Myeloma Working Group consensus criteria places a strong emphasis on the need for more sensitive haematological markers of response driven by the success of novel therapies. One such marker is serum free light chain (sFLC) analysis, which was first incorporated into the definition of stringent complete response in 2006. However, over the past decade there has been some reluctance to extend the role of the sFLC assays to replace 24 h urine electrophoresis for monitoring multiple myeloma (MM). In this review, we lay out the evidence in favour of serum over urine for monoclonal FLC measurements and propose modified criteria for response assignment in myeloma.

Although long intergenic non-coding RNAs (lincRNA) role in various cancers is described, their significance in Multiple Myeloma (MM) remains poorly defined. Here we have studied the lincRNA profile and their clinical impact in MM. We performed RNA-seq on MM cells from 308 newly diagnosed and uniformly treated patients, 16 normal plasma cells and utilized RNA-seq data from 532 newly diagnosed patients from CoMMpass study to analyze for lincRNAs. We observed 869 differentially expressed lincRNAs in MM compared to normal plasma cells. We identified 14 lincRNAs associated with PFS and calculated a risk score to stratify patients. The median PFS between high vs low-risk groups was 17 months vs not-reached (NR); and OS 30 months vs NR, respectively (p < 0.0001 for both). In the independent validation dataset between high and low-risk groups, PFS was 27 vs 42 months (HR 2.06 [1.44-2.96]; p < 0.0005); and 4-year OS 62% vs 86% (HR 2.76 [1.51-5.05]; p < 0.0005) confirming significant clinical relevance of lincRNA in MM. Importantly, lincRNA signature was able to further identify patients with significant differential outcomes within each low and high-risk categories identified using standard risk categorization including cytogenetic/FISH, ISS, and MRD negative or positive. Our results suggest that lincRNAs have an independent effect on MM outcome and provide a rationale to evaluate its molecular and biological impact.

Clonal evolution drives tumor progression, chemoresistance and relapse in cancer. Little is known about clonal selection induced by therapeutic pressure in multiple myeloma. To address this issue, we performed large targeted sequencing of bone marrow plasma cells in 43 multiple myeloma patients at diagnosis and at relapse from exactly the same intensive treatment. The most frequently mutated genes at diagnosis were KRAS (35%), NRAS (28%), DIS3 (16%), BRAF, and LRP1B (12% each). At relapse, the mutational burden was unchanged. Many of the mutations were present at the subclonal level at both time points, including driver ones. According to patients and mutations, we observed different scenarios: selection of a very rare subclone present at diagnosis, appearance, or disappearance of mutations, but also stability. Our data highlight that chemoresistance and relapse could be induced by newly acquired mutations in myeloma drivers but also by (sub)clonal mutations preexisting to the treatment. Importantly, no specific mutation or rearrangement was observed at relapse, demonstrating that intensive treatment has a nonspecific effect on clonal selection in multiple myeloma. Finally, we identified 22 cases of biallelic event, including a double event deletion 17p/TP53mut.

Infections are a major cause of death in patients with multiple myeloma. A post hoc analysis of the phase 3 FIRST trial was conducted to characterize treatment-emergent (TE) infections and study risk factors for TE grade ≥ 3 infection. The number of TE infections/month was highest during the first 4 months of treatment (defined as early infection). Of 1613 treated patients, 340 (21.1%) experienced TE grade ≥ 3 infections in the first 18 months and 56.2% of these patients experienced their first grade ≥ 3 infection in the first 4 months. Risk of early infection was similar regardless of treatment. Based on the analyses of data in 1378 patients through multivariate logistic regression, a predictive model of first TE grade ≥ 3 infection in the first 4 months retained Eastern Cooperative Oncology Group performance status and serum β 2 -microglobulin, lactate dehydrogenase, and hemoglobin levels to define high- and low-risk groups showing significantly different rates of infection (24.0% vs. 7.0%, respectively; P < 0.0001). The predictive model was validated with data from three clinical trials. This predictive model of early TE grade ≥ 3 infection may be applied in the clinical setting to guide infection monitoring and strategies for infection prevention.

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.

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 combination of serum β2-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.

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, β(2)-microglobulin (β(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. β(2)-M and HLC ratios were independently prognostic (P=0.045 and P=0.001). A staging system using β(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.

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.

This retrospective analysis investigated the prognostic value of del(13) and t(4;14) abnormalities and the impact of prior treatment on outcomes in 207 heavily pretreated patients with relapsed or refractory multiple myeloma (MM) treated with lenalidomide plus dexamethasone. Patients with relapsed or refractory MM who had either earlier received thalidomide or bortezomib, or for whom continuation of these agents was contraindicated, and who had fluorescence in situ hybridization data available were included in the analysis. Patients with relapsed or refractory MM who received treatment with lenalidomide plus dexamethasone in the presence of del(13) and t(4;14) chromosomal abnormalities had lower overall response rates (ORRs) and shorter median progression-free survival (PFS) and overall survival (OS) compared with those who did not have these abnormalities. The results also showed that prior treatment with bortezomib was associated with shorter median PFS and OS. Progression during thalidomide therapy was the only significant independent predictor for OS and that the presence of del(13) and hemoglobin levels <10 g per 100 ml were prognostic factors for ORR and PFS, but not OS, in these heavily pretreated relapsed or refractory MM patients treated with lenalidomide plus dexamethasone.

We present a pooled update of two large, multicenter MM-009 and MM-010 placebo-controlled randomized phase III trials that included 704 patients and assessed lenalidomide plus dexamethasone versus dexamethasone plus placebo in patients with relapsed/refractory multiple myeloma (MM). Patients in both studies were randomized to receive 25 mg daily oral lenalidomide or identical placebo, plus 40 mg oral dexamethasone. In this pooled analysis, using data up to unblinding (June 2005 for MM-009 and August 2005 for MM-010), treatment with lenalidomide plus dexamethasone significantly improved overall response (60.6 vs 21.9%, P<0.001), complete response rate (15.0 vs 2.0%, P<0.001), time to progression (median of 13.4 vs 4.6 months, P<0.001) and duration of response (median of 15.8 months vs 7 months, P<0.001) compared with dexamethasone-placebo. At a median follow-up of 48 months for surviving patients, using data up to July 2008, a significant benefit in overall survival (median of 38.0 vs 31.6 months, P=0.045) was retained despite 47.6% of patients who were randomized to dexamethasone-placebo receiving lenalidomide-based treatment after disease progression or study unblinding. Low beta(2)-microglobulin and low bone marrow plasmacytosis were associated with longer survival. In conclusion, these data confirm the significant response and survival benefit with lenalidomide and dexamethasone.

In 2005, the first guidelines were published on the management of patients with multiple myeloma (MM). An expert panel reviewed the currently available literature as the basis for a set of revised and updated consensus guidelines for the diagnosis and management of patients with MM who are not eligible for autologous stem cell transplantation. Here we present recommendations on the diagnosis, treatment of newly diagnosed non-transplant-eligible patients and the management of complications occurring during induction therapy among these patients. These guidelines will aid the physician in daily clinical practice and will ensure optimal care for patients with MM.

Multiple myeloma is the most common indication for high-dose chemotherapy with autologous stem cell support (ASCT) in North America today. Stem cell procurement for ASCT has most commonly been performed with stem cell mobilization using colony-stimulating factors with or without prior chemotherapy. The target CD34+ cell dose to be collected as well as the number of apheresis performed varies throughout the country, but a minimum of 2 million CD34+ cells/kg has been traditionally used for the support of one cycle of high-dose therapy. With the advent of plerixafor (AMD3100) (a novel stem cell mobilization agent), it is pertinent to review the current status of stem cell mobilization for myeloma as well as the role of autologous stem cell transplantation in this disease. On June 1, 2008, a panel of experts was convened by the International Myeloma Foundation to address issues regarding stem cell mobilization and autologous transplantation in myeloma in the context of new therapies. The panel was asked to discuss a variety of issues regarding stem cell collection and transplantation in myeloma especially with the arrival of plerixafor. Herein, is a summary of their deliberations and conclusions.

The phosphoinositide 3-kinase/Akt pathway is an important signalling pathway governing cell survival and proliferation in acute myeloid leukaemia (AML). As full activation of Akt requires phosphorylation on both threonine 308 (Thr308) and serine 473 (Ser473) residues, we studied the level of phosphorylation on the both sites in 58 AML samples by flow cytometry. The ratio of the mean fluorescence intensity of Thr308 and Ser473 represented a continuum ranging from 0.3 to 5.6 and from 0.4 to 2.87, respectively. There were no significant correlations between age, gender, French-American-British classification, leukocytosis, FLT3-ITD and Akt phosphorylation. However, the level of phosphorylation on Thr308, but not on Ser473, was significantly correlated with high-risk karyotype. Thr308(high) patients had significantly shorter overall survival (11 vs 47 months; P=0.01), event-free survival (9 vs 26 months; P=0.005) and relapse-free survival (10 months vs not reached; P=0.02) than Thr308(low) patients. Neither screening for AKT1 E17K mutation nor changes in the level of PTEN expression and phosphorylation could be linked to increased phosphorylation on Thr308 in high-risk cytogenetic AML cells. However, PP2A activity was significantly reduced in high-risk samples compared with intermediate-risk samples. Moreover, the specific Akt inhibitor, Akti-1/2, inhibited cell proliferation and clonogenic properties, and induced apoptosis in AML cells with high-risk cytogenetics, suggesting that Akt may represent a therapeutic target in high-risk AML.

The serum immunoglobulin-free light chain (FLC) assay measures levels of free kappa and lambda immunoglobulin light chains. There are three major indications for the FLC assay in the evaluation and management of multiple myeloma and related plasma cell disorders (PCD). In the context of screening, the serum FLC assay in combination with serum protein electrophoresis (PEL) and immunofixation yields high sensitivity, and negates the need for 24-h urine studies for diagnoses other than light chain amyloidosis (AL). Second, the baseline FLC measurement is of major prognostic value in virtually every PCD. Third, the FLC assay allows for quantitative monitoring of patients with oligosecretory PCD, including AL, oligosecretory myeloma and nearly two-thirds of patients who had previously been deemed to have non-secretory myeloma. In AL patients, serial FLC measurements outperform PEL and immunofixation. In oligosecretory myeloma patients, although not formally validated, serial FLC measurements reduce the need for frequent bone marrow biopsies. In contrast, there are no data to support using FLC assay in place of 24-h urine PEL for monitoring or for serial measurements in PCD with measurable disease by serum or urine PEL. This paper provides consensus guidelines for the use of this important assay, in the diagnosis and management of clonal PCD.

The incidence of venous thromboembolism (VTE) is more than 1 per thousand annually in the general population and increases further in cancer patients. The risk of VTE is higher in multiple myeloma (MM) patients who receive thalidomide or lenalidomide, especially in combination with dexamethasone or chemotherapy. Various VTE prophylaxis strategies, such as low-molecular-weight heparin (LMWH), warfarin or aspirin, have been investigated in small, uncontrolled clinical studies. This manuscript summarizes the available evidence and recommends a prophylaxis strategy according to a risk-assessment model. Individual risk factors for thrombosis associated with thalidomide/lenalidomide-based therapy include age, history of VTE, central venous catheter, comorbidities (infections, diabetes, cardiac disease), immobilization, surgery and inherited thrombophilia. Myeloma-related risk factors include diagnosis and hyperviscosity. VTE is very high in patients who receive high-dose dexamethasone, doxorubicin or multiagent chemotherapy in combination with thalidomide or lenalidomide, but not with bortezomib. The panel recommends aspirin for patients with < or = 1 risk factor for VTE. LMWH (equivalent to enoxaparin 40 mg per day) is recommended for those with two or more individual/myeloma-related risk factors. LMWH is also recommended for all patients receiving concurrent high-dose dexamethasone or doxorubicin. Full-dose warfarin targeting a therapeutic INR of 2-3 is an alternative to LMWH, although there are limited data in the literature with this strategy. In the absence of clear data from randomized studies as a foundation for recommendations, many of the following proposed strategies are the results of common sense or derive from the extrapolation of data from many studies not specifically designed to answer these questions. Further investigation is needed to define the best VTE prophylaxis.

One hundred de novo multiple myeloma patients with t(4;14) treated with double intensive therapy according to IFM99 protocols were retrospectively analyzed. The median overall survival (OS) and event-free survival (EFS) were 41.4 and 21 months, respectively, as compared to 65 and 37 for patients included in the IFM99 trials without t(4;14) (P<10(-7)). We identified a subgroup of patients presenting at diagnosis with both low beta(2)-microglobulin <4 mg/l and high hemoglobin (Hb) >/=10 g/l (46% of the cases) with a median OS of 54.6 months and a median EFS of 26 months, respectively, which benefits from high-dose therapy (HDT); conversely patients with one or both adverse prognostic factor (high beta(2)-microglobulin and/or low Hb) had a poor outcome. The achievement of either complete response or very good partial response after HDT was also a powerful independent prognostic factor for both OS and EFS.

Recent literature suggested that cells of the microenvironment of tumors could be abnormal as well. To address this hypothesis in multiple myeloma (MM), we studied bone marrow mesenchymal stem cells (BMMSCs), the only long-lived cells of the bone marrow microenvironment, by gene expression profiling and phenotypic and functional studies in three groups of individuals: patients with MM, patients with monoclonal gamopathy of undefined significance (MGUS) and healthy age-matched subjects. Gene expression profile independently classified the BMMSCs of these individuals in a normal and in an MM group. MGUS BMMSCs were interspersed between these two groups. Among the 145 distinct genes differentially expressed in MM and normal BMMSCs, 46% may account for a tumor-microenvironment cross-talk. Known soluble factors implicated in MM pathophysiologic features (i.e. IL (interleukin)-6, DKK1) were revealed and new ones were found which are involved in angiogenesis, osteogenic differentiation or tumor growth. In particular, GDF15 was found to induce dose-dependent growth of MOLP-6, a stromal cell-dependent myeloma cell line. Functionally, MM BMMSCs induced an overgrowth of MOLP-6, and their capacity to differentiate into an osteoblastic lineage was impaired. Thus, MM BMMSCs are abnormal and could create a very efficient niche to support the survival and proliferation of the myeloma cells.

New uniform response criteria are required to adequately assess clinical outcomes in myeloma. The European Group for Blood and Bone Marrow Transplant/International Bone Marrow Transplant Registry criteria have been expanded, clarified and updated to provide a new comprehensive evaluation system. Categories for stringent complete response and very good partial response are added. The serum free light-chain assay is included to allow evaluation of patients with oligo-secretory disease. Inconsistencies in prior criteria are clarified making confirmation of response and disease progression easier to perform. Emphasis is placed upon time to event and duration of response as critical end points. The requirements necessary to use overall survival duration as the ultimate end point are discussed. It is anticipated that the International Response Criteria for multiple myeloma will be widely used in future clinical trials of myeloma.

Allogeneic peripheral blood stem cell transplantation (PBSCT) has emerged as an alternative to bone marrow transplantation. PBSCT can be associated with a higher incidence of chronic graft-versus-host disease (cGVHD). In this study, we investigated whether there was a correlation between the composition of PBSC grafts (CD34+ and CD3+ cells) and hematological recovery, GVHD, relapse, and relapse-free survival (RFS) after myeloablative HLA-identical sibling PBSCT. The evolution of 100 acute or chronic leukemia patients was analyzed. Neither hematological recovery, acute or cGVHD, nor relapse, was significantly associated with CD3+ cell dose. Increasing CD34+ stem cells was associated with faster neutrophil (P=0.03) and platelet (P=0.007) recovery. Moreover, 47 of the 78 patients evaluable for cGVHD (60%; 95% CI, 49-71%) developed extensive cGVHD. The probability of extensive cGVHD at 4 years was 34% (95% CI, 21-47%) in patients receiving a 'low' CD34+ cell dose (<8.3 x 10(6)/kg), as compared to 62% (95% CI, 48-76%) in patients receiving a 'high' CD34+ cell dose (>8.3 x 10(6)/kg) (P=0.01). At a median follow-up of 59 months, this has not translated into a difference in relapse. In patients evaluable for cGVHD, RFS was significantly higher in patients receiving a 'low' CD34+ cell dose as compared to those receiving a 'high' CD34+ cell dose (P=0.04). This difference was mainly because of a significantly higher cGVHD-associated mortality (P=0.01). Efforts to accelerate engraftment by increasing CD34+ cell dose must be counterbalanced with the risk of detrimental cGVHD.

Non-myeloablative allogeneic stem cell transplantation has been reported to induce sustained complete remission even in advanced diseases (acute leukemia, lymphomas). The tolerance of this procedure allows treatment of poor candidates to conventional allogeneic transplantation with persisting or relapsing myeloma patients. Twelve patients previously treated with at least VAD regimen and autologous transplantation were included. All patients had a serum beta2 microglobuline >3 mg/l at diagnosis. The conditioning regimen consisted of fludarabine 25 mg/m/day x 5, antithymoglobulin 2.5 mg/kg/day x 5, busulphan 2 mg/kg/day x 2; the transplant was peripheral stem cells (except one) from an HLA-matched sibling and was followed by cyclosporin for 45 to 90 days. This treatment results in a well-tolerated procedure (no mucositis, duration of aplasia <7 days). A dramatic graft anti-myeloma effect is documented even in progressive disease (11/12 PR + CR, 4/12 CR). However, five patients underwent CMV disease, one died of CMV encephalitis (UPN 3) and delayed severe GVHD occurred in four patients. Our data suggest that a better survival could be achieved when patients are transplanted with a controlled disease. In high risk patients, we now propose a non-myeloablative transplantation in addition to the conventional and intensive chemotherapy as first-line of treatment.

In 204 adult patients with de novo acute myeloid leukemia (AML), we prospectively compared allogeneic bone marrow transplantation (alloBMT), autologous stem cell transplantation (ASCT) and chemotherapy (Chemo). 162 patients (79.4%) achieved a complete remission (CR). Of the 135 patients who were still in CR after consolidation, 96 patients were less than 46 years of age: 36 patients had an HLA-identical sibling donor and were allocated for alloBMT (group I); they were compared to the 60 other patients who did not have an HLA-identical sibling donor and were treated with either ASCT or chemotherapy (group II). The 3-year disease-free survival was higher for group I patients (66.5 +/- 16%) than for the 60 group II patients (42.4 +/- 13%) (P < 0.05). The actuarial risk of relapse at 3 years was significantly lower for group I patients (24 +/- 15%) than for the other 60 group II patients (56 +/- 13%; P < 0.009). By multivariate analysis, the disease-free survival and risk of relapse were influenced by the initial WBC count (P < 0.02 and P < 0.006), the number of chemotherapy courses for CR (P < 0.001 and P < 0.01) and the type of post-induction treatment (alloBMT vs no alloBMT; P < 0.1 and P < 0.02). The 99 patients who did not fulfill the inclusion criteria for alloBMT were given intensive chemotherapy including high-dose aracytine. When they were still in CR (n = 77), these patients were then randomized for either ASCT (n = 39) or Chemo (n = 38). We were unable to detect any statistical difference between ASCT and Chemo for either disease-free survival, risk of relapse or survival. These results indicate that alloBMT seems to produce results which are at least superior to those of other therapeutic modalities. The results of either ASCT or Chemo look similar.

A prospective randomized study was conducted comparing the efficacy and toxicity of two anthracyclines for the treatment of patients with acute myeloid leukemia (AML) between 55 and 75 years. A total of 220 patients were randomized to receive as induction chemotherapy cytosine arabinoside (Ara-C: 100 mg/m2/day; continuous infusion for 7 days) combined with either daunorubicin (DNR: 50 mg/m2/day, i.v. bolus for 3 days) (n=108) or idarubicin (IDA: 8 mg/m2/day, i.v. bolus for 5 days) (n=112). The complete remission (CR) rate was similar (P=0.296) after IDA (76/112; 68%) and DNR (66/108; 61%) (P=0.3). For patients aged 55-65, the CR rate was significantly higher after IDA (39/47; 83%) than after DNR (29/50; 58%) (P=0.007). Persistent leukemia was more frequent after DNR (26/108) than after IDA (13/112; P=0.015). Hematological and extra-hematological toxicities were similar. The CR patients were given a consolidation course of chemotherapy with Ara-C: 50 mg/m2/12 h, subcutaneously for 5 days, combined with either DNR:30 mg m2/day, i.v. bolus for 3 days or IDA:8 mg/m2/day i.v. bolus for 3 days according to the initial randomization, and then received a continuous maintenance treatment for 2 years. The survival and disease-free survival (DFS) were similar in both groups; there was no difference in the risk of relapse. However, there was a trend for a longer event-free survival (EFS) in the IDA group than for the DNR patients (P=0.07). Our results seem to indicate that IDA is probably more efficient than DNR for AML patients between 55 and 75 years, and confirm the data published in other studies comparing prospectively IDA and DNR in adults.

We report here two patients with polycythemia vera (PV) who developed secondary non-Hodgkin's lymphoma (NHL). Both cases were high grade B-cell NHL. Cytogenetic analysis of bone marrow and lymph node was performed in each case and showed numerous chromosomal abnormalities. Of interest, chromosomal abnormalities of the PV and of the NHL clones were different, suggesting the possible involvement of two different clones. A 11q23 breakpoint was common between the two cases and the putative role of this breakpoint in the pathogenesis of the NHLs is discussed.

Myeloperoxidase (MPO) has recently been shown in an in vitro, cell-free system to catalyze the peroxidative degradation of vincristine (VCR). Oxidation of VCR involves a ring fission between positions 20' and 21', and is thought to be facilitated by the presence of an hydroxyl (-OH) group at position 20'. We report here two different approaches, both with potential clinical application, to decrease MPO-catalyzed vinca degradation. Firstly, we tested the hypothesis that -OH substitution at position 20' increases vinca susceptibility to peroxidation by comparing the relative extent of degradation of vinorelbine (Navelbine or NVB), which lacks a 20' hydroxyl substitution, with that of VCR. As anticipated, NVB was significantly less susceptible to MPO-catalyzed peroxidation than was VCR (p < 0.01). Secondly, we screened an array of compounds that are in current clinical use for their ability to inhibit MPO. Acetaminophen, N-acetylcysteine, propylthiouracil, D-penicillamine, mefenamic acid, dapsone, and methimazole all inhibited MPO at clinically achievable concentrations. Insofar as increased MPO activity has been observed in patients with acute myeloid leukemia, these findings suggest potential strategies for improving the activity of vinca alkaloids in this disease.

Myeloperoxidase (MPO), a heme-peroxidase found in the HL-60 myeloblastic cell line, is involved in vincristine (VCR) metabolism and the inactivation of this drug. We have examined whether decreased MPO activity correlated with increased sensitivity to VCR toxicity in myeloid leukemia cells. We have used MPO antisense RNA to reduce 60% of the MPO activity in the HL-60 cells. The MPO-deficient HL-60 cell line, C15, was significantly more sensitive to VCR than the parental MPO-positive cell line. Both cell lines were negative for P170-glycoprotein expression. Conversely, an MPO-positive C15 subclone was more resistant to VCR than the MPO-deficient C15 cell line. No significant differences in cytotoxic effects were observed between MPO-positive and MPO-deficient cells, following treatment with either daunorubicin or actinomycin D, two multidrug resistance-related drugs. These results strongly support an important role for MPO in VCR resistance in HL-60 cells. Antisense manipulation of the MPO content of myeloid cells could be of potential interest in leukemia treatment.

This study aimed to evaluate the effect of melphalan on both terminal divisions and self-renewal capacity of acute myeloblastic leukemia (AML) progenitors (colony-forming units, CFU-L) grown in methylcellulose. Terminal divisions and self-renewal were assayed by primary (PE1) and secondary (PE2) colony formation, respectively. Thirteen cases of AML, were tested. Melphalan induced a negative exponential dose-effect on CFU-L survival. Moreover, melphalan was equally effective in inhibiting CFU-L growth in both PE1 and PE2 assays, with D10 values of 1.53 +/- 0.17 micrograms/ml and 1.59 +/- 0.21 micrograms/ml for PE1 and PE2, respectively (p = 0.48). Cytotoxicity of melphalan on CFU-L did not differ significantly from that observed for normal hemopoietic granulocyte-macrophage colony-forming units, erythroid burst-forming units, and granulocyte-erythroid-macrophage-megakaryocyte progenitors. Mafosfamide-lysine, a stable cyclophosphamide congener, strongly inhibited primary colony formation (PE1) with a D10 value of 14.46 +/- 1.76 micrograms/ml, but was much less efficient in the PE2 assay. Our findings suggest that the self-renewal capacity of AML progenitors can be differentially affected by alkylating agents. Moreover, since it is now considered that chemotherapy should be preferentially directed against the self-renewal of leukemic progenitors, melphalan might offer a greater potential than cyclophosphamide or cyclophosphamide derivatives in the therapy of AML.

The normal counterparts of the B cells found in hairy cell leukemia (HCL) are not known. We report here a detailed morphological, cytochemical, immunological and molecular analysis of a patient with B-cell chronic lymphocytic leukemia (B-CLL) who later in the course of his disease developed hairy cell leukemia. We speculate that hairy cell transformation of B-CLL might be related to an in vivo protein kinase C mediated cellular activation of B-CLL cells.