Ulrich Dührsen

Immunochemotherapy With Rituximab and Cyclophosphamide, Doxorubicin, Vincristine, and Prednisone Significantly Improves Response and Time to Treatment Failure, But Not Long-Term Outcome in Patients With Previously Untreated Mantle Cell Lymphoma: Results of a Prospective Randomized Trial of the German Low Grade Lymphoma Study Group (GLSG)

PURPOSE Mantle cell lymphoma (MCL) is characterized by a poor prognosis with a low to moderate sensitivity to chemotherapy and a median survival of only 3 to 4 years. In an attempt to improve outcome, the German Low Grade Lymphoma Study Group (GLSG) initiated a randomized trial comparing the combination of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) and rituximab (R-CHOP) with CHOP alone as first-line therapy for advanced-stage MCL. PATIENTS AND METHODS One hundred twenty-two previously untreated patients with advanced-stage MCL were randomly assigned to six cycles of CHOP (n = 60) or R-CHOP (n = 62). Patients up to 65 years of age achieving a partial or complete remission underwent a second randomization to either myeloablative radiochemotherapy followed by autologous stem-cell transplantation or interferon alfa maintenance (IFNalpha). All patients older than 65 years received IFNalpha maintenance. RESULTS R-CHOP was significantly superior to CHOP in terms of overall response rate (94% v 75%; P = .0054), complete remission rate (34% v 7%; P = .00024), and time to treatment failure (TTF; median, 21 v 14 months; P = .0131). No differences were observed for progression-free survival. Toxicity was acceptable, with no major differences between the two therapeutic groups. CONCLUSION The combined immunochemotherapy with R-CHOP resulted in a significantly higher response rate and a prolongation of the TTF as compared with chemotherapy alone. Hence, R-CHOP may serve as a new baseline regimen for advanced stage MCL, but needs to be further improved by novel strategies in remission.

Inflammatory reactions and severe neutropenia in mice lacking the transcriptional repressor Gfi1.

The transcriptional repressor Gfi1 is a nuclear zinc-finger protein expressed in T-cell precursors in the thymus and in activated mature T lymphocytes. Previous experiments have shown that Gfi1 is involved in T-cell lymphomagenesis and in the development of T-cell progenitors. Here we show that Gfi1 is also expressed outside the lymphoid system in granulocytes and activated macrophages, cells that mediate innate immunity (that is, non-specific immunity). We have generated Gfi1-deficient mice (Gfi1−/−) and show that these animals are severely neutropenic and accumulate immature monocytic cells in blood and bone marrow. Their myeloid precursor cells are unable to differentiate into granulocytes upon stimulation with granulocyte colony–stimulating factor (G-CSF) but can develop into mature macrophages. We found that Gfi1−/− macrophages produce enhanced levels of inflammatory cytokines, such as tumor necrosis factor (TNF), interleukin-10 (IL-10) and IL-1β, when stimulated with bacterial lipopolysaccharide (LPS) and that Gfi1−/− mice succumb to low doses of this endotoxin that are tolerated by wildtype mice. We conclude that Gfi1 influences the differentiation of myeloid precursors into granulocytes or monocytes and acts in limiting the inflammatory immune response.

Subcutaneous Alemtuzumab in Fludarabine-Refractory Chronic Lymphocytic Leukemia: Clinical Results and Prognostic Marker Analyses From the CLL2H Study of the German Chronic Lymphocytic Leukemia Study Group

PURPOSE The phase II CLL2H trial evaluated safety and efficacy of subcutaneous alemtuzumab in patients with fludarabine-refractory chronic lymphocytic leukemia (CLL). Clinical and biologic markers were evaluated for their impacts on outcome. PATIENTS AND METHODS One hundred nine patients were enrolled, and 103 received at least one dose of alemtuzumab. After dose escalation, alemtuzumab was administered subcutaneously at 30 mg three times weekly for up to 12 weeks. Response was assessed every 4 weeks during treatment and quarterly thereafter. RESULTS The overall response rate was 34% (complete response, 4%; partial response, 30%). The median progression-free survival was 7.7 months, and the median overall survival (OS) was 19.1 months. Grades 3 to 4 neutropenia, thrombocytopenia, and anemia occurred in 56%, 57%, and 49% of patients, respectively. Grades 3 to 4 noncytomegalovirus and cytomegalovirus infections occurred in 29% and 8% of patients, respectively. Injection-site skin reactions were generally mild. Efficacy did not vary significantly in subgroups defined by genetic parameters (in particular, in 17p deletion, 11q deletion, mutated TP53, and unmutated VH), but efficacy was inferior in patients with increased beta2-microglobulin (beta2-MG) and thymidine kinase (TK). In multivariate analysis of clinical and biologic variables, age, performance status, beta2-MG, and TK were independent prognostic factors for OS. CONCLUSION Subcutaneous alemtuzumab appears as effective and safe as intravenous alemtuzumab in fludarabine-refractory CLL. Subcutaneous administration should be the preferred delivery route because of its efficacy, convenience, improved adverse effect profile, and cost savings. In contrast to chemotherapy-based therapy, alemtuzumab treatment overcomes the adverse prognostic impact of VH mutation status, TP53 mutation, and genomic aberrations.

Administration of bortezomib before and after autologous stem cell transplantation improves outcome in multiple myeloma patients with deletion 17p

In patients with multiple myeloma (MM), risk stratification by chromosomal abnormalities may enable a more rational selection of therapeutic approaches. In the present study, we analyzed the prognostic value of 12 chromosomal abnormalities in a series of 354 MM patients treated within the HOVON-65/GMMG-HD4 trial. Because of the 2-arm design of the study, we were able to analyze the effect of a bortezomib-based treatment before and after autologous stem cell transplantation (arm B) compared with standard treatment without bortezomib (arm A). For allanalyzed chromosomal aberrations, progression-free survival (PFS) and overall survival (OS) were at least equal or superior in the bortezomib arm compared with the standard arm. Strikingly, patients with del(17p13) benefited the most from the bortezomib-containing treatment: the median PFS in arm A was 12.0 months and in arm B it was 26.2 months (P = .024); the 3 year-OS for arm A was 17% and for arm B it was 69% (P = .028). After multivariate analysis, del(17p13) was an independent predictor for PFS (P < .0001) and OS (P < .0001) in arm A, whereas no statistically significant effect on PFS (P = .28) or OS (P = .12) was seen in arm B. In conclusion, the adverse impact of del(17p13) on PFS and OS could be significantly reduced by bortezomib-based treatment, suggesting that long-term administration of bortezomib should be recommended for patients carrying del(17p13).

ZAP-70 expression is a prognostic factor in chronic lymphocytic leukemia.

B-cell chronic lymphocytic leukemia (B-CLL) is a heterogenous disease with a highly variable clinical course. Recent studies have shown that expression of the protein tyrosine kinase ZAP-70 may serve as a prognostic marker in B-CLL. Employing a semiquantitative RT-PCR assay, we examined purified leukemia B cells of 39 CLL patients for the expression of ZAP-70 mRNA transcripts. Significant ZAP-70 mRNA levels exceeding those found in control samples with 5% T cells were detected in 36% of the CLL cases. Patients in the ZAP-70 positive cohort were characterized by an unfavorable clinical course with a significantly shorter progression-free survival as compared to the ZAP-70-negative patients (64%). These results were confirmed by flow-cytometric analysis of the ZAP-70 protein, and expanded to a larger patient cohort (n=67). A combined statistical analysis of 79 patients showed that the two patient subgroups also differed with regard to overall survival and a panel of known clinical prognostic factors including LDH, thymidine kinase serum levels and expression of the CD38 surface antigen by the leukemic cell clone. The level of ZAP-70 expression did not change over time in the majority of patients where sequential samples were available for analysis.

Combined analysis of ZAP-70 and CD38 expression as a predictor of disease progression in B-cell chronic lymphocytic leukemia

Prognostic predictions in B-cell chronic lymphocytic leukemia (B-CLL) at early clinical stage are based on biological disease parameters, such as ZAP-70 and CD38 protein levels, genomic aberrations as well as immunoglobulin variable heavy chain gene (IgVH) mutation status. In the current study, ZAP-70 and CD38 expressions were examined by flow cytometry in 252 patients with B-CLL. Cytoplasmic ZAP-70 expression in more than 20% (ZAP-70+) and surface CD38 expression on more than 30% (CD38+) of B-CLL cells were associated with an unfavorable clinical course. The levels of ZAP-70 and CD38 did not change over time in the majority of patients where sequential samples were available for analysis. Combined analysis of ZAP-70 and CD38 yielded discordant results in 73 patients (29.0%), whereas 120 patients (47.6%) were concordantly negative and 59 patients (23.4%) were concordantly positive for ZAP-70 and CD38 expression. Median treatment-free survival times in patients whose leukemic cells were ZAP-70+CD38+ was 30 months as compared to 130 months in patients with a ZAP-70−CD38− status. In patients with discordant ZAP-70/CD38 results, the median treatment-free survival time was 43 months. Thus, ZAP-70 and CD38 expression analyses provided complementary prognostic information identifying three patient subgroups with good, intermediate and poor prognosis. Over-representation of high-risk genomic aberrations such as 17p deletion or 11q deletion and distribution of the IgVH mutation status in B-CLL discordant for ZAP-70/CD38 pointed toward a distinct biologic background of the observed disease subgroups. This finding was also supported by microarray-based gene expression profiling in a subset of 35 patients. The expression of 37 genes differed significantly between the three groups defined by their expression of ZAP-70 and CD38, including genes that are involved in regulation of cell survival and chemotherapy resistance.

CD38 expression is an important prognostic marker in chronic lymphocytic leukaemia

Employing a multicolour flow cytometry assay, 133 B-chronic lymphocytic leukaemia (B-CLL) cases were analysed for surface expression of CD38. Based on a cut-off value of 20%, CLL patients were categorised into a CD38-positive (⩾20%, n = 56) and a CD38-negative subgroup (<20%, n = 77) and separately analysed for clinical and laboratory parameters. Patients in the CD38-positive cohort were characterised by an unfavourable clinical course with a more advanced disease stage, poor responsiveness to chemotherapy, short time to initiation of first treatment and shorter survival. In contrast, the CD38- negative group required minimal or no treatment, remained treatment-free for a longer time period and had prolonged survival (P < 0.05). CD38 expression was a robust marker in the majority of patients in that it was stable over time and not significantly influenced by chemotherapy. In conclusion, our data confirm recent studies suggesting a role of CD38 as a predictor of clinical outcome in patients with B-CLL.

Imatinib compared with chemotherapy as front-line treatment of elderly patients with Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph+ALL).

Elderly patients with Philadelphia chromosome‐positive acute lymphoblastic leukemia (Ph+ALL) have a poor prognosis, with a low complete remission (CR) rate, high induction mortality, and short remission duration. Imatinib (IM) has a favorable toxicity profile but limited antileukemic activity in advanced Ph+ALL. Imatinib in combination with intensive chemotherapy has yielded promising results as front‐line therapy, but its value as monotherapy in newly diagnosed Ph+ALL is not known.

Rituximab Maintenance Therapy After Autologous Stem-Cell Transplantation in Patients With Relapsed CD20+ Diffuse Large B-Cell Lymphoma: Final Analysis of the Collaborative Trial in Relapsed Aggressive Lymphoma

PURPOSE The standard treatment for relapsed diffuse large B-cell lymphoma (DLBCL) is salvage chemotherapy followed by high-dose therapy and autologous stem-cell transplantation (ASCT). The impact of maintenance rituximab after ASCT is not known. PATIENTS AND METHODS In total, 477 patients with CD20(+) DLBCL who were in their first relapse or refractory to initial therapy were randomly assigned to one of two salvage regimens. After three cycles of salvage chemotherapy, the responding patients received high-dose chemotherapy followed by ASCT. Then, 242 patients were randomly assigned to either rituximab every 2 months for 1 year or observation. RESULTS After ASCT, 122 patients received rituximab, and 120 patients were observed only. The median follow-up time was 44 months. The 4-year event-free survival (EFS) rates after ASCT were 52% and 53% for the rituximab and observation groups, respectively (P = .7). Treatment with rituximab was associated with a 15% attributable risk of serious adverse events after day 100, with more deaths (six deaths v three deaths in the observation arm). Several factors affected EFS after ASCT (P < .05), including relapsed disease within 12 months (EFS: 46% v 56% for relapsed disease after 12 months), secondary age-adjusted International Prognostic Index (saaIPI) more than 1 (EFS: 37% v 61% for saaIPI < 1), and prior treatment with rituximab (EFS: 47% v 59% for no prior rituximab). A significant difference in EFS between women (63%) and men (46%) was also observed in the rituximab group. In the Cox model for maintenance, the saaIPI was a significant prognostic factor (P < .001), as was male sex (P = .01). CONCLUSION In relapsed DLBCL, we observed no difference between the control group and the rituximab maintenance group and do not recommend rituximab after ASCT.

Acute Myelogenous Leukemia-Induced Sympathetic Neuropathy Promotes Malignancy in an Altered Hematopoietic Stem Cell Niche

Perivascular mesenchymal stem and progenitor cells (MSPCs) are critical for forming a healthy hematopoietic stem cell (HSC) niche. However, the interactions and influence of acute myelogenous leukemia (AML) stem cells with the microenvironment remain largely unexplored. We have unexpectedly found that neuropathy of the sympathetic nervous system (SNS) promotes leukemic bone marrow infiltration in an MLL-AF9 AML model. Development of AML disrupts SNS nerves and the quiescence of Nestin(+) niche cells, leading to an expansion of phenotypic MSPCs primed for osteoblastic differentiation at the expense of HSC-maintaining NG2(+) periarteriolar niche cells. Adrenergic signaling promoting leukemogenesis is transduced by the β2, but not β3, adrenergic receptor expressed on stromal cells of leukemic bone marrow. These results indicate that sympathetic neuropathy may represent a mechanism for the malignancy in order to co-opt the microenvironment and suggest separate mesenchymal niche activities for malignant and healthy hematopoietic stem cells in the bone marrow.