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Biomedical subjects

Michael Schleuning

Publications and source records attributed to Michael Schleuning.

8 recordsLinked to original sources

Long-term survival in refractory acute myeloid leukemia after sequential treatment with chemotherapy and reduced-intensity conditioning for allogeneic stem cell transplantation.

A sequential regimen of chemotherapy, reduced-intensity conditioning (RIC) for allogeneic stem cell transplantation (SCT), and prophylactic donor lymphocyte transfusion (pDLT) was studied in 103 patients with refractory acute myeloid leukemia (AML). According to published criteria, refractoriness was defined by primary induction failure (PIF; n = 37), early (n = 53), refractory (n = 8), or second (n = 5) relapse. Chemotherapy consisted of fludarabine (4 x 30 mg/m(2)), cytarabine (4 x 2 g/m(2)), and amsacrine (4 x 100 mg/m(2)), followed 4 days later by RIC, comprising 4 Gy total body irradiation (TBI), cyclophosphamide, and antithymocyte globulin. Patients without graft-versus-host disease (GvHD) at day +120 received pDLT in escalating doses. Patients' median age was 51.8 years. Before conditioning, 99 patients had active disease, 3 were aplastic, 1 was in second complete remission (CR2). Forty-one patients had family donors, 62 had unrelated donors. With a 25-month median follow-up, overall survival (OS) at 1, 2, and 4 years was 54%, 40%, and 32%; the respective leukemia-free survival (LFS) was 47%, 37%, and 30%. Patients with PIF showed a 2-year OS of 62.5%. OS was 87% in 17 patients receiving pDLT. One-year cumulative incidence of leukemic death and non-relapse-mortality was 28.7% and 17.2%. In a multivariate analysis, more than 2 courses of prior chemotherapy were the strongest predictor for poor outcome (P = .007; HR = 3.01 [OS]; P = .002; HR = 3.25 [LFS]). These results indicate a high activity of the regimen in refractory AML.

Acute Disease↗

The effect of prior exposure to imatinib on transplant-related mortality.

BACKGROUND AND OBJECTIVES: Imatinib is an effective treatment for chronic myeloid leukemia (CML) and Philadelphia chromosome-positive (Ph+) acute lymphoblastic leukemia (ALL). However, relapse is common in patients with advanced or high risk disease. Such patients may be eligible for allogeneic stem cell transplantation (SCT), raising the question whether imatinib therapy may compromise the outcome of subsequent SCT. DESIGN AND METHODS: We retrospectively analyzed 70 patients with CML and 21 with Ph+ ALL who had received imatinib prior to SCT. Data were retrieved by directly contacting centers. Multivariate analysis was used to define factors associated with major outcomes (engraftment, graft-versus-host disease, relapse, non-relapse mortality) in addition to descriptive statistics. For the CML patients major outcomes were compared with those of historical controls drawn from the EBMT registry. RESULTS: At SCT, 44% of CML patients were in accelerated phase or blast crisis and 40% of ALL patients had active disease compared to 84% and 95% prior to imatinib. At 24 months, estimated transplant-related mortality was 44% and estimated relapse mortality 24%. Factors associated with shorter overall and progression-free survival were advanced disease at SCT and a female donor/male recipient pairing. No unusual organ toxicities were observed. Compared to historical controls, prior imatinib treatment did not influence overall survival, progression-free survival or non-relapse mortality, while there was a trend towards higher relapse mortality and significantly less chronic graft-versus-host disease. INTERPRETATION AND CONCLUSIONS: Within the limits of a heterogeneous and relatively small cohort of patients, we found no evidence that imatinib negatively affects major outcomes after SCT, suggesting that imatinib prior to SCT is safe.

Adolescent↗

Sequential regimen of chemotherapy, reduced-intensity conditioning for allogeneic stem-cell transplantation, and prophylactic donor lymphocyte transfusion in high-risk acute myeloid leukemia and myelodysplastic syndrome.

PURPOSE: To improve the effect of allogeneic stem-cell transplantation by sequential use of intensive chemotherapy, reduced-intensity conditioning (RIC), and prophylactic donor lymphocyte transfusions (pDLTs) in high-risk acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS). PATIENTS AND METHODS: In a prospective study of 75 consecutive patients (median age, 52.3 years), high risk was defined by progressive or refractory disease (n = 59), second remission after early relapse (n = 8), or first remission with poor prognosis based on cytogenetics or delayed response to induction therapy (n = 8). Unfavorable karyotypes were found in 49% of informative patients, and 68 patients had medical contraindications against standard conditioning. Fludarabine (30 mg/m2), cytarabine (2 g/m2), and amsacrine (100 mg/m2) for 4 days were used for cytoreduction. After 3 days of rest, RIC consisted of 4 Gy total-body irradiation, antithymocyte globulin, and 80 to 120 mg/kg cyclophosphamide. Thirty-one patients had an HLA-identical sibling donor; 44 patients had an unrelated and/or HLA-mismatched donor. pDLT was given from day +120 in patients who were not receiving immunosuppression and were free of graft-versus-host disease (GvHD). RESULTS: Complete remission was induced in 66 patients (88%). With a median follow-up of 35.1 months (range, 13.6 to 47.6 months), 2-year overall and leukemia-free survival were 42% and 40%, respectively. Outcome of patients with refractory disease or with complex cytogenetic aberrations was identical to that of better prognostic subgroups. Survival was best in patients who received high CD34+ cell numbers, and in patients with limited GvHD. CONCLUSION: Sequential use of intensive chemotherapy, RIC transplantation, and pDLT represents a promising approach to the treatment of high-risk AML and MDS, particularly in patients with most unfavorable prognoses.

Adolescent↗

Impact of human herpesvirus-6 after haematopoietic stem cell transplantation.

We studied 228 consecutive stem cell transplant recipients, screened for reactivation of human herpesvirus-6 (HHV-6) in peripheral blood and other specimens as clinically indicated by means of qualitative polymerase chain reaction. Among them, 197 received an allograft and 31 autograft. Ninety-six of 228 patients (42.1%) showed HHV-6 reactivation in peripheral blood and 129 of 228 (56.6%) demonstrated HHV-6 in at least one of the specimens tested. 41.9% of patients were asymptomatic when HHV-6 was identified. Clinical features, noted when HHV-6 was detected, included interstitial or alveolar pneumonia, gastroduodenal and colorectal disease, bone marrow suppression and liver disease. However, based on clinical and histopathological criteria, HHV-6 was considered a causal agent in only a minority of patients, in particular, those suffering from bone marrow suppression (n = 11), gastroduodenitis (five), colitis (three), interstitial/alveolar pneumonia (five), skin rash (one), pericarditis (two) and encephalitis (one). HHV-6 reactivation was significantly associated with the occurrence of graft-versus-host disease [odds ratio (OR) 5.31], Epstein-Barr virus coinfection (OR 8.89) and unrelated donor transplantation (OR 5.67) indicating an increased stage of immunosuppression.

Adolescent↗

Intravenous ribavirin for eradication of respiratory syncytial virus (RSV) and adenovirus isolates from the respiratory and/or gastrointestinal tract in recipients of allogeneic hematopoietic stem cell transplants.

In a retrospective analysis, we identified 38 evaluable patients who received intravenous ribavirin after adenovirus or RSV detection in the respiratory and/or gastrointestinal tract throughout the years 1998 and 2001. A total of 43 treatment cycles are analyzed. Intravenous ribavirin was combined with cidofovir in about half of the patients. In six out of eight patients treated because of RSV isolates from the respiratory tract, the virus was no longer detectable after treatment. In case of adenovirus isolates, the treatment was efficacious in eradicating the virus from the respiratory tract in more than 60% and from the gastrointestinal tract in 75% of treatment cycles. The addition of cidofovir was not beneficial in eradicating RSV isolates, but somewhat improved the virus clearance of adenovirus. Virus clearance was associated with a trend to a better median survival after virus detection. There were some episodes of suspected hemolysis and a trend towards lower leukocyte counts, reaching grade 3 toxicity in about 15% of treatment cycles. However, in general, intravenous ribavirin was well tolerated. In conclusion, the possible efficacy of intravenous Ribavirin in controlling RSV or adenovirus infections after allogeneic stem cell transplantations should be evaluated in prospective clinical trials.

Adenoviridae↗

Tolerance and chimerism.

Stem-cell transplantation from human leukocyte antigen (HLA)-haploidentical family members carries a high risk of rejection and graft-versus-host disease (GVHD) if donor and recipient differ by more than one HLA antigen. The authors have developed treatment protocols from studies in dog leukocyte antigen-haploidentical dogs that prevent rejection and modify GVHD to the extent that patients with aggressive hematologic neoplasia can be treated with success. Principal improvements have been achieved in the use of cyclophosphamide and total-body irradiation for conditioning and T-cell depletion for prevention of GVHD. More recently, the combination of marrow and CD6-depleted mobilized donor blood cells (MDBC) has been introduced for HLA-haploidentical transplantation on the basis that CD6-depleted MDBC contain immunoregulatory cells besides stem cells and natural killer cells. Clinical results are reported on 36 patients with high-risk hematologic neoplasia. The results encourage the use of HLA-haploidentical stem-cell transplantation at an earlier stage of the disease. This method could also be of use for tolerance induction in organ transplantation.

Animals↗

Adoptive immunotherapy in chimeras with donor lymphocytes.

Allogeneic stem cell transplantation has a well-defined indication in the treatment of hematological malignancies. The beneficial immune effect of allogeneic marrow transplantation has long been known, but only recently have methods been developed to separate the graft-versus-leukemia (GVL) effect from graft-versus-host disease (GVHD). Animal experiments have shown that lymphocytes from the marrow donor can be transfused without causing severe GVHD if stable chimerism and tolerance is established. First clinical studies have been preformed in patients with recurrent chronic myelogenous leukemia. In these patients complete molecular remissions were induced that persist without further maintenance treatment. These results have been confirmed in larger multicenter studies in Europe and the USA. The best results were obtained in chronic myelogenous leukemia (CML); repeated successes have been reported in relapsing acute myeloid leukemia (AML), myelodysplastic syndromes and multiple myeloma (MMY), and rare responses were reported for acute lymphoid leukemia. Contrary to animal experiments GVHD has been observed in human patients although to a lesser extent than expected in transplants not given immunosuppression. Secondly myelosuppression has been observed in patients treated with relapsing CML. In CML the incidence of GVHD could be reduced by depleting CD8+ T cells from the donor lymphocyte concentrate. Alternatively only small numbers of T lymphocytes can be transfused and in the case of failing responses, the numbers of donor lymphocytes may be increased. Results in recurrent AML have been improved by the use of low-dose cytosine arabinoside, granulocyte-macrophage colony-stimulating factor and granulocyte colony-stimulating factor mobilized blood cells as compared to lymphocytes only. In MMY the response rate is higher than in AML, but the remissions are of limited duration in most patients. Several protocols have been designed to include preemptive donor lymphocyte transfusion in patients with a high relapse risk after transplantation. Problems remain to avoid chronic GVHD and to circumvent the immune escape mechanisms of leukemia.

Adoptive Transfer↗

Hematopoietic stem cell transplantation after reduced-intensity conditioning as treatment of sickle cell disease.

OBJECTIVE: Sickle cell disease generates considerable morbidity and mortality. Allogeneic hematopoietic stem cell transplantation (SCT) has the potential of curing the disease and halting end-organ damage. However, in older patients this treatment is associated with a significant risk of toxicity and death. SCT after reduced-intensity conditioning (RIC) might be a safer approach for the treatment of sickle cell disease. MATERIALS AND METHODS: A 22-year-old male had experienced multiple, life-threatening hemolytic crises. We treated him with G-CSF-mobilized stem cells from his heterozygote, human leukocyte antigen-matched brother after RIC with fludarabine and cyclophosphamide. GVHD prophylaxis consisted of cyclosporine (CyA) and mycophenolate mofetil (MMF). Chimerism of peripheral blood mononuclear cells was evaluated using short tandem repeat analysis and hemoglobin analysis was performed by high-performance liquid chromatography. RESULTS: There were no major treatment-related toxicities. At day +30 after transplantation the patient had mixed hematopoietic chimerism, which later converted to full chimerism. Hemoglobin analysis revealed 3.4% HbA(2), 1.0% HbF, and 41.2% HbS, which essentially is the same hemoglobin partition as in his brother's blood. MMF was discontinued on day +35 and CyA on day +120. After discontinuation of CyA the patient developed mild chronic GVHD, which resolved with continued CyA, low-dose steroids, and the retinoid isotretinoin. He is doing well on day +315 without evidence of GVHD. CONCLUSIONS: Allogeneic SCT after RIC is feasible in adult patients with sickle cell disease. Mixed chimerism is sufficient to relieve disease-related symptoms and is possibly correlated with less acute GVHD.

Adult↗