Initial chemotherapy with mitoxantrone, chlorambucil, prednisone impairs the collection of stem cells in patients with indolent lymphomas—results of a randomized comparison by the German Low-Grade Lymphoma Study Group

The UK NCRI study of chlorambucil, mitoxantrone and dexamethasone (CMD) versus fludarabine, mitoxantrone and dexamethasone (FMD) for untreated advanced stage follicular lymphoma: molecular response strongly predicts prolonged overall survival

We present a long-term follow-up of the UK chlorambucil, mitoxantrone and dexamethasone (CMD) versus fludarabine, mitoxantrone and dexamethasone (FMD) for untreated advanced, symptomatic follicular lymphoma (FL). This trial was the first to prospectively assess molecular response and the impact on outcomes for 400 patients. The median progression-free survival (PFS) and overall survival (OS) for CMD were 3·6 and 14·6 years vs. 3·0 and 15·7 years for FMD, respectively. Estimates for Restricted Mean Survival Time (RMST) suggested no difference in PFS or OS. For the whole cohort there was a highly significant difference in survival by POD24, with a median OS from a risk-defining event of 3·9 years compared to 13·7 years for all others (RMST P < 0·001). Molecular remission was achieved in 25/46 patients (54·3%) in the CMD arm and 20/41 (48·8%) in the FMD arm (P = 0·6). Molecular negativity resulted in median PFS of 5·6 years vs. 2·3 years for molecularly positive (log-rank P < 0·001) and median OS not reached versus 12·5 years (log-rank P < 0·01). No cases of progression occurred in minimal residual disease (MRD) negative patients after six years of follow-up. Although there was no difference in outcomes between arms, this is the first prospective study to report MRD negativity resulting in significantly improved OS.

Advances in stem cell mobilization

Use of granulocyte colony stimulating factor (G-CSF)-mobilized peripheral blood hematopoietic progenitor cells (HPCs) has largely replaced bone marrow (BM) as a source of stem cells for both autologous and allogeneic cell transplantation. With G-CSF alone, up to 35% of patients are unable to mobilize sufficient numbers of CD34 cells/kg to ensure successful and consistent multi-lineage engraftment and sustained hematopoietic recovery. To this end, research is ongoing to identify new agents or combinations which will lead to the most effective and efficient stem cell mobilization strategies, especially in those patients who are at risk for mobilization failure. We describe both established agents and novel strategies at various stages of development. The latter include but are not limited to drugs that target the SDF-1/CXCR4 axis, S1P agonists, VCAM/VLA-4 inhibitors, parathyroid hormone, proteosome inhibitors, Groβ, and agents that stabilize HIF. While none of the novel agents have yet gained an established role in HPC mobilization in clinical practice, many early studies exploring these new pathways show promising results and warrant further investigation.

High-dose therapy with autologous stem cell transplantation versus chemotherapy or immuno-chemotherapy for follicular lymphoma in adults

BACKGROUND

Follicular lymphoma (FL) is the most common indolent and second most common Non-Hodgkin`s lymphoma (NHL) in the Western world. Standard treatment usually includes rituximab and chemotherapy. High-dose therapy (HDT) followed by autologous stem cell transplantation (ASCT) is an option for patients in advanced stages or for second-line therapy, leading to improved progression-free survival (PFS) rates. However, the impact of HDT and ASCT remains unclear, as there are hints of an increased risk of second cancers.

OBJECTIVES

We performed a systematic review with meta-analysis of randomised controlled trials (RCTs) comparing HDT plus ASCT with chemotherapy or immuno-chemotherapy in patients with FL with respect to overall survival (OS), PFS, treatment-related mortality (TRM), adverse events and secondary malignancies.

SEARCH METHODS

We searched CENTRAL, MEDLINE, and EMBASE as well as conference proceedings from January 1985 to September 2011 for RCTs. Two review authors independently screened search results.

SELECTION CRITERIA

Randomised controlled trials comparing chemotherapy or immuno-chemotherapy with HDT followed by ASCT in adults with previously untreated or relapsed FL.

DATA COLLECTION AND ANALYSIS

We used hazard ratios (HR) as effect measures used for OS and PFS as well as relative risks for response rates. Two review authors independently extracted data and assessed the quality of trials.

MAIN RESULTS

Our search strategies led to 3046 potentially relevant references. Of these, five RCTs involving 1093 patients were included; four trials in previously untreated patients and one trial in relapsed patients. Overall, the quality of the five trials is judged to be moderate. All trials were reported as randomised and judged to be open-label studies, because usually trials evaluating stem cell transplantation are not blinded. Due to the small number of studies in each analysis (four or less), the quantification of heterogeneity was not reliable and not evaluated in further detail. A potential source of bias are uncertainties in the HR calculation. For OS, the HR had to be calculated for three trials from survival curves, for PFS for two trials.We found a statistically significant increased PFS in previously untreated FL patients in the HDT + ASCT arm (HR = 0.42 (95% confidence interval (CI) 0.33 to 0.54; P < 0.00001). However, this effect is not transferred into a statistically significant OS advantage (HR = 0.97; 95% 0.76 to 1.24; P = 0.81). The subgroup of trials adding rituximab to both intervention arms (one trial) confirms these results and the trial had to be stopped early after an interim analysis due to a statistically significant PFS advantage in the HDT + ASCT arm (PFS: HR = 0.36; 95% CI 0.23 to 0.55; OS: HR = 0.88; 95% CI 0.40 to 1.92). In the four trials in previously untreated patients there are no statistically significant differences between HDT + ASCT and the control-arm in terms of TRM (RR = 1.28; 95% CI 0.25 to 6.61; P = 0.77), secondary acute myeloid leukaemia/myelodysplastic syndromes (RR = 2.87; 95% CI 0.7 to 11.75; P = 0.14) or solid cancers (RR = 1.20; 95% CI 0.25 to 5.77; P = 0.82). Adverse events were rarely reported and were observed more frequently in patients undergoing HDT + ASCT (mostly infections and haematological toxicity).For patients with relapsed FL, there is some evidence (one trial, N = 70) that HDT + ASCT is advantageous in terms of PFS and OS (PFS: HR = 0.30; 95% CI 0.15 to 0.61; OS: HR = 0.40; 95% CI 0.18 to 0.89). For this trial, no results were reported for TRM, adverse events or secondary cancers.

AUTHORS' CONCLUSIONS

In summary, the currently available evidence suggests a strong PFS benefit for HDT + ASCT compared with chemotherapy or immuno-chemotherapy in previously untreated patients with FL. No statistically significant differences in terms of OS, TRM and secondary cancers were detected. These effects are confirmed in a subgroup analysis (one trial) adding rituximab to both treatment arms. Further trials evaluating this approach are needed to determine this effect more precisely in the era of rituximab. Moreover, longer follow-up data are necessary to find out whether the PFS advantage will translate into an OS advantage in previously untreated patients with FL.There is evidence that HDT + ASCT is advantageous in patients with relapsed FL.

Current status of stem cell mobilization

New advances in effective mobilization of peripheral blood stem cells have permitted a greater proportion of patients to benefit from autologous stem cell transplantation. In this review, the relative merits of peripheral blood and mobilized bone marrow are discussed. All available agents are reviewed. A critical assessment of the appropriate dosing and frequency of available growth factors is undertaken, and the most commonly used chemotherapy plus growth factor combinations are covered. Specific recommendations for patients who are poor mobilizers are dealt with including the role of plerixafor.

Ifosfamide, epirubicin and etoposide rituximab in refractory or relapsed B-cell lymphoma: analysis of remission induction and stem cell mobilization

Chemotherapy with ifosfamide, epirubicin and etoposide (IEV) is an effective treatment regimen for refractory/relapsed non-Hodgkin lymphoma (NHL). Rituximab has been shown to improve response rates, progression-free survival and overall survival in B-cell NHL. This study included 85 patients who were treated with IEV or rituximab-IEV (R-IEV) for refractory/relapsed B-cell NHL. The overall response rate was 40.7% (IEV) versus 68.8% (R-IEV). Fever occurred after 23.4% of IEV and 19.4% of R-IEV cycles. 94.9% of patients mobilized sufficient numbers of CD34+ cells (IEV) versus 93.8% (R-IEV). Fifty-five patients (64.7%) proceeded to high-dose therapy after IEV+/-rituximab. The median survival time was 60.0 months (IEV) and 19.5 months (R-IEV), and has not been reached for patients who received high-dose therapy. The addition of rituximab to IEV salvage chemotherapy increases the response rates in B-cell NHL without affecting stem cell mobilization, but overall survival for patients proceeding to high-dose chemotherapy is not improved.

Long-term results of the treatment of patients with mantle cell lymphoma with cladribine (2-CDA) alone (95-80-53) or 2-CDA and rituximab (N0189) in the North Central Cancer Treatment Group

BACKGROUND

The objective of this study was to test cladribine (2-CDA) alone and in combination with rituximab in patients with mantle cell lymphoma (MCL).

METHODS

Patients with MCL were treated on 2 sequential trials. In Trial 95-80-53, patients received 2-CDA as initial therapy or at relapse. In Trial N0189, patients received combination 2-CDA and rituximab as initial therapy. In both trials, 2-CDA was administered at a dose of 5 mg/m2 intravenously on Days 1 through 5 every 4 weeks for 2 to 6 cycles, depending on response. In Trial N0189, rituximab 375 mg/m2 was administered on Day 1 of each cycle.

RESULTS

Results were reported for 80 patients. Twenty-six previously untreated patients and 25 patients who had recurrent disease with a median age of 68 years received single-agent 2-CDA. The overall response rate (ORR) was 81% with 42% complete responses (CRs) in the previously untreated group. The median progression-free survival (PFS) was 13.6 months (95% confidence interval [95% CI], 7.2-22.1 months), and 81% of patients remained alive at 2 years. The ORR was 46% with a 21% CR rate in the recurrent disease group. The median PFS was 5.4 months (95% CI, 4.6-13.1 months), and 36% of patients remained alive at 2 years. Twenty-nine eligible patients with a median age of 70 years received 2-CDA plus rituximab. The ORR was 66% (19 of 29 patient), and the CR rate was 52% (15 of 29 patients). The median duration of response for patients who achieved a CR had not been reached at the time of the current report, and only 3 of the patients who achieved a CR developed recurrent disease at a median follow-up of 21.5 months.

CONCLUSIONS

2-CDA had substantial single-agent activity in both recurrent and untreated MCL, and the results indicated that it may be administered safely to elderly patients. The addition of rituximab to 2-CDA may increase the duration of response.