CD34(+) lineage specific donor cell chimerism for the diagnosis and treatment of impending relapse of AML or myelodysplastic syndrome after allo-SCT.

After allo-SCT, analysis of CD34(+) lineage-specific donor cell chimerism (DCC) is a sensitive method for monitoring minimal residual disease in patients with AML or myelodysplastic syndrome (MDS) with CD34 expression. To substantiate evidence of whether immune interventions in patients with impending relapse, defined by incomplete lineage-specific DCC, may prevent hematological relapse, we performed a retrospective nested case control study. Unsorted and lineage-specific DCC were measured in 134 patients. Forty-three patients had an incomplete CD34(+)-DCC with no other evidence of relapse. After immediate tapering of immunosuppressive treatment (30 patients) and/or infusion of donor lymphocytes (10 patients), 21 patients remained in remission (conversion to complete lineage-specific DCC) and 22 relapsed. Relapse-free survival at 3 years of the 91 patients with stable DCC and of the 43 patients with incomplete DCC was 74% (95% confidence interval (CI), 64-83%) and 40% (95% CI, 24-58%), respectively. OS rates were 79% (95% CI, 70-88%) and 52% (95% CI, 35-69%), respectively. These results, with 49% of patients with impending relapse successfully treated with immune intervention, highly suggest that analysis of CD34(+)-DCC is an important tool for monitoring and the management of AML and MDS patients after allo-SCT.

The harvest and use of autologous back-up grafts for graft failure or severe GVHD after allogeneic hematopoietic stem cell transplantation: a survey of the European Group for Blood and Marrow Transplantation.

Autologous hematopoietic stem cells (HSCs) harvested as back-up prior to allogeneic hematopoietic SCT (HSCT) may potentially be useful in the treatment of graft failure or in cases with severe GVHD. Here, we studied the general policies and indications for autologous back-up harvest among the European Group for Blood and Marrow Transplantation centers in the year 2003. The outcome of patients receiving autologous back-up transfusion between 1998 and 2002 was evaluated retrospectively. The responses from 94 centers showed that 48 centers had a general policy with variable indications for autologous back-up harvest. Thirty-five patients with graft failure (25), GVHD (8) or relapse (2) retransplanted with autologous back-ups were reported. Autologous back-up transfusion was performed at a median of 35 days (patients with graft failure) or 90 days (patients with GVHD) after allogeneic HSCT. Within 100 days after autologous HSCT, 21 patients died from treatment-related complications (19) or relapse (2). Estimated overall survival at 1 year was 16% (95% CI 0-32%) for patients treated for graft failure and 13% (95% CI 0-37%) for GVHD patients. In conclusion, our data demonstrate that the indication for autologous back-up harvests is limited and that general storage and use cannot be recommended unless in selected prospective studies.

Treatment effects of high-dose antithrombin without concomitant heparin in patients with severe sepsis with or without disseminated intravascular coagulation.

BACKGROUND: Disseminated intravascular coagulation (DIC) is a serious complication of sepsis that is associated with a high mortality. OBJECTIVES: Using the adapted International Society on Thrombosis and Haemostasis (ISTH) diagnostic scoring algorithm for DIC, we evaluated the treatment effects of high-dose antithrombin (AT) in patients with severe sepsis with or without DIC. PATIENTS AND METHODS: From the phase III clinical trial in severe sepsis (KyberSept), 563 patients were identified (placebo, 277; AT, 286) who did not receive concomitant heparin and had sufficient data for DIC determination. RESULTS: At baseline, 40.7% of patients (229 of 563) had DIC. DIC in the placebo-treated patients was associated with an excess risk of mortality (28-day mortality: 40.0% vs. 22.2%, P < 0.01). AT-treated patients with DIC had an absolute reduction in 28-day mortality of 14.6% compared with placebo (P = 0.02) whereas in patients without DIC no effect on 28-day mortality was seen (0.1% reduction in mortality; P = 1.0). Bleeding complications in AT-treated patients with and without DIC were higher compared with placebo (major bleeding rates: 7.0% vs. 5.2% for patients with DIC, P = 0.6; 9.8% vs. 3.1% for patients without DIC, P = 0.02). CONCLUSIONS: High-dose AT without concomitant heparin in septic patients with DIC may result in a significant mortality reduction. The adapted ISTH DIC score may identify patients with severe sepsis who potentially benefit from high-dose AT treatment.

Transplantation strategies in AML: AMLCG data.

Allogeneic stem cell transplantation (allo-SCT) is considered the most potent postremission therapy for acute myeloid leukemia (AML). Its superior antileukemic activity is largely ascribed to the powerful graft-versus-leukemia (GvL) effects exerted by donor lymphocytes. However, due to considerable treatment-related lethality the gains in relapse prevention do not necessarily translate into survival advantages in the overall patient population. Therefore, allo-SCT for adult patients with AML in first complete remission (CR1) is currently recommended only for younger and medically fit patients who are at intermediate to high risk of relapse and have an HLA-identical sibling donor. Stem cell allografting from alternative donors in CR1 is considered an option for high risk patients as defined by cytogenetic abnormalities or incomplete response after one course of induction chemotherapy and should usually be performed in the context of a clinical protocol.

Thalidomide for the treatment of acute myeloid leukemia.

In analogy to solid neoplasms, accumulating data suggest the requirement of angiogenesis also for the development and progression of hematopoietic malignancies including acute myeloid leukemia (AML). Inhibition of increased microvessel density in bone marrow (BM) might be a promising target for pharmacological interventions aimed at reducing disease activity. Among the putative inhibitors of angiogenesis, thalidomide has demonstrated a considerable efficacy in myelodysplastic syndromes (MDS) and AML with overall response rates up to 56% and 25%, respectively. Responders experienced hematologic improvements with increased hemoglobin and platelet counts resulting in temporary transfusion independence. In AML, partial responses--defined as reduction of the leukemic blast cell infiltration of at least 50% in BM--occurred in four of 20 patients after one month of thalidomide administration in a previous phase I/II study. Additionally, we observed a long-term response in one AML patient of more than 20 months, meanwhile fulfilling the criteria of complete remission. The decrease in leukemic blast infiltration in BM of responders was accompanied by a significant reduction of the microvessel density. Overall adverse events caused by the drug consisted mainly of fatigue, constipation, skin rash and polyneuropathy with a tolerable dose of 200-400 mg p.o. per day. In conclusion, thalidomide as a single agent has significant anti-leukemic activity with some evidence for anti-angiogenic effects in BM, although the precise mechanism of action remains to be elucidated.

Evidence of a graft-versus-leukemia effect in chronic lymphocytic leukemia after reduced-intensity conditioning and allogeneic stem-cell transplantation: the Cooperative German Transplant Study Group.

PURPOSE: To study whether hematopoietic stem-cell transplantation (HSCT) after reduced-intensity conditioning is effective and tolerable in patients with advanced chronic lymphocytic leukemia (CLL). PATIENTS AND METHODS: Thirty patients with advanced B-cell CLL were included into the study. After reduced-intensity conditioning with fludarabine, busulfan, and antithymocyte globulin, patients received a transplant from related (n = 15) or unrelated donors (n = 15). Minimal residual disease (MRD) was monitored with a clone-specific polymerase chain reaction. RESULTS: After a median follow-up of 2 years, 23 patients are alive (to date). Neutrophil and platelet engraftment occurred after a median of 17.5 and 15 days, respectively. Acute graft-versus-host disease (GVHD) grade 2 to 4 was observed in 17 patients (56%), and chronic GVHD was observed in 21 patients (75%). Twelve patients (40%) achieved a complete remission (CR), and 16 patients (53%) achieved a partial remission. Late CR occurred up to 2 years after transplantation. MRD was monitored in eight patients with CR. All patients achieved a molecular CR. At last follow-up, six patients were in ongoing molecular CR. Causes of death were treatment-related complications in four patients and progressive disease in three patients. The probability of overall survival, progression-free survival, and nonrelapse mortality at 2 years was 72% (95% confidence interval [CI], 54% to 90%), 67% (95% CI, 49% to 85%), and 15% (95% CI, 1% to 29%), respectively. CONCLUSION: Treatment-related mortality after reduced-intensity conditioning followed by allogeneic HSCT was low. The procedure induced molecular remissions in patients with advanced CLL. The observation of late remissions provided evidence of a graft-versus-leukemia effect.

Reduced intensity conditioning for allogeneic hematopoietic stem cell transplantation in patients with acute myeloid leukemia: disease status by marrow blasts is the strongest prognostic factor.

We analyzed predictive factors for the outcome of 113 acute myeloid leukemia patients receiving reduced-intensity conditioning prior to allogeneic hematopoietic stem cell transplantation (HSCT). Patients were ineligible for conventional-intensity HSCT. Conditioning consisted of fludarabine and 50% of the conventional dose of busulfan (n=93) or total body irradiation (n=20). The source of stem cells was blood in 102 patients, marrow in 10, and both in one. In total, 50 (44.2%) donors were HLA-matched siblings, 50 (44.2%) unrelated fully matched and 13 (11.5%) partially mismatched family (n=1) or unrelated (n=12) donors. In all, 107 (94.6%) patients showed neutrophil and platelet engraftment after a median time of 13.5 and 13 days. The probabilities of event-free survival (EFS) (median follow-up: 12 months) were 49% for patients with less than 5% blasts in the marrow, 24% for patients with 5-20% blasts (P=0.002) and 14% with >20% blasts (P

Early tandem high-dose ifosfamide, carboplatin, etoposide therapy with stem cell rescue for small-cell lung cancer: brief report on the results of a phase-I/II trial.

OBJECTIVE: High-dose therapy (HDT) for small-cell lung cancer is experimental. Late intensification HDT for chemosensitive disease can increase the number and quality of remissions and prolong relapse-free survival, but has not yet shown impact on overall survival. This is possibly due to resistant residual disease. To overcome the development of resistance, we have tested early intensification tandem HDT. METHODS: We performed a phase-I/II trial using 1 conventional cycle of ifosfamide, carboplatin, etoposide (ICE) plus granulocyte colony-stimulating factor for stem cell recruitment followed by 2 cycles of high-dose ICE with rescue by CD34+ cell-enriched peripheral blood mononuclear cells. Dose escalation was performed for the 2 high-dose ICE cycles. Radiotherapy for limited disease was according to standard protocols. RESULTS: 17 patients were entered: 2 female patients; 15 male patients; median age 53 (range 36-65) years; 2 patients with limited disease, and 15 patients with extensive disease. We treated 4 patients at dose level 1, 11 patients at level 2, and 2 patients at level 3. The maximum tolerable dose was at level 2 with neuropathy being dose-limiting. Overall, toxicity was < or = grade 2 for all patients up to dose level 2 with hematotoxicity being grade 4 for all patients. There were 15 partial remissions (88%), 1 no change (6%), and 1 progressive disease (6%). Median time to progression was 7.9 months. Overall survival was 12.9 months (median). CONCLUSIONS: Early intensification with this protocol is feasible. Although a comparatively good response rate and median time to progression have been observed in this group dominated by patients with extensive disease, overall survival is short and no substantial long-term survival was found.

Overexpression of vascular endothelial growth factor (VEGF) and its cellular receptor KDR (VEGFR-2) in the bone marrow of patients with acute myeloid leukemia.

Vascular endothelial growth factor (VEGF) and its cellular receptor VEGFR-2 have been implicated as the main endothelial pathway required for tumor neovascularization. However, the importance of the VEGF/VEGFR-2 system for angiogenesis in hematologic malignancies such as AML remains to be elucidated. In 32 patients with newly diagnosed untreated AML, we observed by immunohistochemical analysis of bone marrow biopsies significantly higher levels of VEGF and VEGFR-2 expression than in 10 control patients (P <0.001). In contrast, VEGFR-1 staining levels in AML patients were in the same range as in the controls. Expression of VEGF and VEGFR-2 was significantly higher in patients with a high degree of microvessel density compared to those with a low degree (VEGF: P =0.024; VEGFR-2: P =0.040) and correlated well with bone marrow microvessel density (r(s)=0.566 and 0.609, respectively; P <0.001). Furthermore, in patients who achieved a complete remission following induction chemotherapy VEGFR-2 staining levels decreased into the normal range. In conclusion, our results provide evidence for increased expression of VEGF/VEGFR-2 of leukemic blasts and correlation with angiogenesis in the bone marrow of AML patients. Thus, VEGF/VEGFR-2 might constitute promising targets for antiangiogenic and antileukemic treatment strategies in AML.

Reduced non-relapse mortality after reduced intensity conditioning in advanced chronic lymphocytic leukemia.

We studied in 30 patients with progressive or relapsing chronic lymphocytic leukemia (CLL) if hematopoietic stem cell transplantation (HSCT) after conditioning with fludarabine, busulfan and ATG is effective and if treatment related mortality can be reduced compared to myeloablative conditioning regimens. Patients had 15 matched related and 15 matched unrelated donors. Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporine alone or a combination with "short course" methotrexate or mycophenolate mofetil. The median follow-up is 24 months. At last follow up 11 patients were in complete and 13 in partial remission. Six patients had stable or progressive disease. Late complete remissions occurred up to one year after transplantation and the number of patients with CR is still increasing. Four patients died due to treatment related complications resulting in a probability of treatment-related mortality of 15% (CI 95%, 1% to 29%) at 2 years. The probability of overall survival and progression free survival at two years was 79% and 61%, respectively. In conclusion, HSCT after reduced conditioning may lower the treatment-related toxicity and has the capacity to induce complete remissions.

[Angiogenesis in patients with hematologic malignancies]. / Angiogenese bei hämatologischen Neoplasien.

Angiogenesis in Patients with Hematologic Malignancies The importance of angiogenesis for the progressive growth and viability of solid tumors is well established. Emerging data suggest an involvement of angiogenesis in the pathophysiology of hematologic malignancies as well. Recently, we and others have reported increased angiogenesis in the bone marrow of patients with acute myeloid leukemia (AML) and normalization of bone marrow microvessel density when patients achieved a complete remission (CR) after induction chemotherapy. Tumor angiogenesis depends on the expression of specific mediators that initiate a cascade of events leading to the formation of new microvessels. Among these, VEGF (vascular endothelial growth factor), FGF (fibroblast growth factor) and angiopoietins play a pivotal role in the induction of neovascularization in solid tumors. These cytokines stimulate migration and proliferation of endothelial cells and induce angiogenesis in vivo. Recent data suggest an important role for these mediators in hematologic malignancies as well. Isolated AML blasts overexpress VEGF and VEGF receptor 2. Thus, the VEGF/VEGFR-2 pathway can promote the growth of leukemic blasts in an autocrine and paracrine manner. Therefore, neovascularization and angiogenic mediators/receptors may be promising targets for anti-angiogenic and anti-leukemic treatment strategies. The immunomodulatory drug thalidomide inhibits angiogenesis in animal models. Moreover, it has significant activity in refractory multiple myeloma. In a current phase II study for patients with primary refractory or relapsed multiple myeloma using a combination of thalidomide with hyperfractionated cyclophosphamide and dexamethasone (Hyper-CDT), we observed a partial remission in 12 of 14 evaluable patients (86%). Thus, this combination seems to be very potent. Furthermore, we evaluated the safety and efficacy of thalidomide in patients with AML not qualifying for intensive cytotoxic chemotherapy. 20 patients aged 58-85 (median 69) years were recruited to this phase I/II study and were treated with a dose of 200-400 mg per os daily for a duration of 1-40 (median 6) weeks, dependent on the individual tolerability of the drug. In 4 patients we observed a partial response (PR - defined as more than 50% reduction in leukemic blast infiltration in the bone marrow). This was accompanied by an increase in platelet counts and hemoglobin values. One additional patient showed a significant improvement of peripheral blood counts without fulfilling the criteria of a PR. In parallel, we observed a significant decrease in microvessel density in these 5 patients during treatment with thalidomide. In conclusion, thalidomide seems to have anti-angiogenic as well as anti-leukemic activity in AML. The VEGF/VEGFR-2 pathway seems to play an important role in AML. Therefore, receptor tyrosine kinase inhibitors like SU5416 or SU6668 are currently evaluated in the context of phase II studies in AML. We could recently induce a stable remission in a patient with second relapse of her AML refractory towards chemotherapy by administration of SU5416 (compassionate use), a tyrosine kinase inhibitor of VEGFR-2 and ckit. Current and future studies will clarify the role of anti-angiogenic treatment strategies in AML and other hematologic malignancies.

Kinetics of standardized large volume leukapheresis (LVL) in patients do not show a recruitment phenomenon of peripheral blood progenitor cells (PBPC).

Although several studies have demonstrated the efficacy of large volume leukapheresis (LVL) to yield high numbers of peripheral blood progenitor cells (PBPC), the mechanisms of stem cell release into circulation and the postulated phenomenon of PBPC recruitment during apheresis have not been investigated in detail. Therefore, we analyzed the kinetics of stem cell enrichment in a total of 34 standardized LVL for patients with hematologic malignancies (lymphoma, multiple myeloma) and solid tumors (breast cancer, rhabdomyosarcoma). LVL was started 2 h after administration of G-CSF processing six times the patient's blood volume. Cells were sequentially collected into six bags and the numbers of leukocytes, mononuclear cells (MNC), CD34+ cells and colony-forming cells (CFU-GM) in each collection bag were analyzed. The numbers of PBPC collected demonstrated a continuous decrease starting after an early maximum during the second processed blood volume (P = 0.001). Interestingly, these kinetics of decreasing stem cell yields during LVL were similar for both entities of patients with hematologic malignancies as well as for both groups of patients with solid tumors. In summary, a recruitment phenomenon, defined as a time-dependent and LVL-induced increase of PBPC, could not be demonstrated in any of the diseases investigated.