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Biomedical subjects

W Knauf

Publications and source records attributed to W Knauf.

At least 37 records · Page 2Linked to original sources
PubMed1998

HIV-related non-Hodgkin's lymphoma: CHOP induction therapy and interferon-alpha-2b/zidovudine maintenance therapy.

In a prospective multicenter study 68 out of 158 patients with HIV infection and malignant lymphoma were assigned to a risk-adapted induction therapy using the following algorithm: High-risk patients fulfilled 2 of 3 criteria: T4 lymphocytes <50/microL; WHO activity index 3 or 4; pre-existing AIDS-defining opportunistic infection. Normal-risk patients received 4 to 6 cycles of CHOP chemotherapy; those that achieved complete remission (CR) received zidovudine (500 mg/d) and interferon-alpha maintenance therapy (5 million units three times a week) for one year. High-risk patients received low-dose CHOP or vincristine/prednisone chemotherapy. Supportive care was performed with pentamidine inhalation and G-CSF. Intrathecal (it) methotrexate was given for CNS prophylaxis. The median survival was 634 days for 38 patients of the normal-risk group and 129 days for 30 patients of the high-risk group. 18 high-risk patients treated with low-dose CHOP had better survival (156 days) than 12 patients treated with vincristine/prednisone (72 days p=0.044). 68% of the patients in the normal-risk group achieved complete remission. 5 out of 18 high-risk patients treated with low-dose CHOP achieved complete remission. Three normal-risk patients developed fatal opportunistic infections during chemotherapy. Immune parameters deteriorated after CHOP induction and partially recovered with maintenance treatment. We conclude that the normal-risk patients survived longer than reported in most published studies. Toxicity was low. Low-dose CHOP seems to be superior to vincristine/prednisone therapy in high-risk patients.

Adult↗
PubMed1996

Fatal Mucor pneumonia after treatment with 2-chlorodeoxyadenosine for non-Hodgkin's-lymphoma.

Fungal infections, in addition to bacterial and opportunistic infections such as Pneumocystis carinii pneumonia, may evolve in patients with infectious complications due to iatrogenic immunosuppression. Aside from common Candida and Aspergillus species, rare fungi like Mucor must be considered in patients with neutropenia or prolonged impaired T-cell function. Here we report on a patient with a low grade lymphoma who was treated with 2-chlorodeoxyadenosine because of disease progression. After recovery from Pneumocystis carinii pneumonia he presented again with clinical signs of pneumonia. No pathogen was found on bronchoscopy and he died rapidly. In the lungs a massive necrosis was seen in which nonseptated hyphae identified as Mucor species were demonstrated.

Aged↗
PubMed1996

Interferon-alpha 2b (IFN alpha) for early-phase chronic lymphocytic leukaemia with high risk for disease progression: results of a randomized multicentre study.

The efficacy of interferon-alpha 2b (IFN alpha) to prolong progression-free (PFS) and/or overall survival (OS) in early B-CLL (Binet stage A) was examined in a risk-adapted phase III study. 99 previously untreated B-CLL patients were recruited. 44 patients with expected high risk for disease progression, defined by non-nodular bone marrow infiltration and lymphocyte doubling time < or = 12 months or serum thymidine kinase levels > or = 5 U/I, were randomized to either receive IFN alpha (group 1, n = 21) or not (group 2, n = 23). 55 low-risk patients were observed to evaluate this risk stratification (group 3). During a median observation time of 36 months, four patients in the IFN alpha group achieved a partial remission (PR), no patient had stable disease (SD), and 17 patients experienced progressive disease (PD). The four responders had less extensive disease at study entry and tended to exhibit a rise in serum IgG levels. In group 2, no PR, seven SD and 16 PD, whereas in group 3, no PR, 37 SD and 18 PD occurred. PFS in group 1 (6.7 months) was not different from group 2 (13.3 months, P = 0.22), but PFS of groups 1 and 2 differed from group 3 (37 months, P < or = 0.001). OS was 44.9 months (group 1), 43.1 months (group 2) and 57.9 months (group 3). OS was not significantly different for group 1 v 2, but was significant between groups 1 and 3 (P = 0.023). The higher percentage of PD in group 2 compared to group 3 (70% v 29%) shows that the selected risk factors allow the definition of CLL stage A patients at risk for disease progression within about a year. In conclusion, our data indicate that IFN alpha does not prolong PFS or OS in stage A CLL patients with high risk for disease progression.

Aged↗
PubMed1991

[Malignant lymphoma associated with HIV infection].

The course of disease in 119 HIV-infected patients (117 men, 2 women; median age 38.5 years) with malignant tumours other than Kaposi's sarcoma was analyzed in a multi-centre retrospective study. This was conducted to obtain initial information concerning the incidence, clinical features and results of therapy in HIV-associated neoplasms, especially malignant lymphomas. The most frequent tumour was malignant non-Hodgkin's lymphoma (98 patients, 82.5%), seven patients had Hodgkin's disease, five had solid tumours, four a polyclonal lymphoproliferative syndrome, three an acute lymphocytic leukaemia, and two had other lymphoproliferative diseases. 58% of the non-Hodgkin's lymphomas occurred in patients with marked immunodeficiency, 85% were high grade malignancies and 47% had primary extranodal disease. 56% of primary nodal lymphomas also had visceral spread (Stage IV). Lymphoblastic non-Hodgkin's lymphoma was more common in patients with favourable immunological status, presented less frequently with primary extranodal disease, was diagnosed earlier than other non-Hodgkin's lymphomas, and appeared to carry a better prognosis. 78 out of the 98 patients with non-Hodgkin's lymphoma had been treated, 66 with cytotoxics. The median survival time was 6 months. Longer remission periods, of at least 12 months, were seen in ten of the 78 patients (13%). Despite the overall poor prognosis and the pre-existing immune defect, palliative (chemo-)therapeutic measures are both justified and promising, and may also result in life-prolonging remissions.

Adult↗
PubMed1991

Autologous transplantation of an immunomagnetic bead purged marrow in patients with relapsed acute lymphoblastic leukemia.

In acute lymphoblastic leukemia (ALL) the expected duration of a second complete remission (CR) following conventional aggressive multi-drug treatment is rather short, and long-term survival is rarely seen. Myeloablative consolidation treatment with ABMT in second CR is thought to benefit "high risk" patients thus allowing the escalation of cytoreductive treatment into a lethal range. In three patients with relapsed ALL bone marrow was collected in the very early second remission phase. The autografts were incubated with a panel of monoclonal antibodies bound to magnetobeads (DYNABEADS M450). The pretransplant regimen consisted of total body irradiation (TBI) (14.4 Gy) and cyclophosphamide (CY) (50 mg/kg b.w. x4). Following autologous transplantation of those immunomagnetobead purged marrow grafts, complete hematologic reconstitution was seen in all three patients. They are alive and disease-free for +26, +24 and +17 months post transplant, which is also proven by the absence of detectable gene rearrangements after transplantation. In two of them disease-free survival exceeds the duration of the preceding remission y 20 and 12 months respectively, which is a definitive parameter for therapy effectiveness. Therefore, "high dose" consolidation treatment in very early second CR followed by autologous transplantation of purged bone marrow seems to allow long-term disease-free survival. The technique of ex vivo immunomagnetic bead purging, i.e. the "direct" and "indirect" method of binding monoclonal antibodies to magnetobeads is described.

Antibodies, Monoclonal↗
PubMed1990

Activation of lymphocytes induced by recombinant human granulocyte-macrophage colony-stimulating factor in patients with malignant lymphoma.

To investigate effects of recombinant human granulocyte-macrophage colony-stimulating factor (rhGM-CSF) on lymphoid cells in vivo, we monitored changes in absolute lymphocyte counts, plasma concentrations of soluble interleukin-2 receptor (sIL-2R) and soluble cytotoxic/suppressor (sCD8) antigens, and phenotypic changes of surface membrane antigens of peripheral mononuclear cells from 14 patients with malignant lymphoma treated with rhGM-CSF. Eight of the 14 patients had relapsed or had refractory non-Hodgkin's lymphoma (NHL) and received rhGM-CSF after intensive chemotherapy with novantrone (NO) and high-dose Ara-C (AC) (NOAC) as salvage regimen. Six other patients with NHL or Hodgkin's disease (HD) were in complete remission and treated with rhGM-CSF to enhance peripheral hematopoietic progenitor cell harvest for autografting. An increase in absolute lymphocyte count at the zenith of leukocyte elevation and a drastic increase in concentration of sIL-2R from a median of 565 U/mL to 6,700 U/mL on rhGM-CSF infusion were found in all patients. There was also a moderate increase in sCD8 levels from a median of 277 U/mL to 470 U/mL. Ten patients were available for serial studies of phenotypic changes in surface membrane antigens. A significant increase in CD25+ (IL-2R+) (P = .0020) and CD4+ (P = .0137) lymphocytes was observed in all patients, but no significant change in CD3+, CD8+, TCR delta 1+, or CD19+ cells. Elevations in absolute lymphocyte counts or in concentrations of sIL-2R or sCD8 were not observed in four other patients during recovery from intensive chemotherapy without rhGM-CSF support. Our results provide evidence that administration of rhGM-CSF might activate lymphocytes in vivo. The impact of this activation on the remission rate and duration, as well as survival in patients with NHL, warrants further investigation.

Antigens, CD↗
PubMed1990

[MR-tomographic quantification of infiltrative bone marrow changes and therapeutic follow-up of patients with hairy cell leukemia].

The effect of treatment on bone marrow infiltration in hairy cell leukaemia was followed by means of MRT in five patients. A semi-quantitative method has been developed in order to judge the effect of treatment. The results correlate well with the findings on iliac crest biopsies. The method could partly replace the invasive iliac crest biopsies, which are used for therapy monitoring.

Bone Marrow↗
PubMed1990

Autologous blood stem-cell transplantation in patients with advanced Hodgkin's disease and prior radiation to the pelvic site.

Patients with relapsed Hodgkin's disease who respond to salvage therapy are successfully treated with cyclophosphamide, carmustine (BCNU), and etoposide (VP-16) (CBV) followed by autologus bone marrow transplantation (ABMT). Because of heavy pretreatment including radiation to the pelvic site, marrow harvest was not feasible in those patients. We therefore used blood-derived hemopoietic precursor cells as an alternative stem-cell source to rescue them after superdose chemotherapy. Hemopoietic precursor cells were mobilized into the peripheral blood either by chemotherapeutic induction of transient myelosuppression followed by an overshooting of blood stem-cell concentration, or by continuous intravenous (IV) granulocyte-macrophage colony-stimulating factor (GM-CSF) administration. The median time to reach 1,000 WBC per microliter, 500 polymorphonuclear cells (PMN) per microliter, or 20,000 platelets per microliter was 10, 20.5, and 38 days, respectively, for 50% of all patients. The platelet counts of two patients never dropped below 20,000/microL following autologous blood stem-cell transplantation (ABSCT), whereas two other patients had to be supported with platelets for 75 and 86 days posttransplant until a stable peripheral platelet count of 20,000/microL was attained. Among the 11 assessable patients, seven are in unmaintained complete remission (CR) at a median follow-up of 318 days. This is a first report on a series of ABSCTs in patients with advanced Hodgkin's disease proving that, despite prior damage to the marrow site, the circulating stem-cell pool is still a sufficient source of hemopoietic precursor cells for stem-cell rescue.

Adult↗
PubMed1990

Successful autologous transplantation of blood stem cells mobilized with recombinant human granulocyte-macrophage colony-stimulating factor.

We investigated the effect of recombinant human granulocyte-macrophage colony-stimulating factor (rhuGM-CSF) on the pool of circulating hemopoietic progenitor cells in 11 patients with hematological malignancies of nonmyeloid origin and 1 patient with sarcoma. These patients were eligible for autologous blood stem cell transplantation rather than autologous bone marrow transplantation because sufficient marrow aspirates could not be performed due to damage at the usual sites of bone marrow harvest by previous chemo- and/or radiotherapy. Recombinant human GM-CSF was given as continuous i.v. infusion via central venous line for a median time of 11.5 days (range 5-22 days), during which a median number of six aphereses were performed. In comparison to the pretreatment level the median increase in the number of granulocyte-macrophage colony-forming units (CFU-GM)/ml of peripheral blood was 8.5-fold. In all 12 patients a median decrease of the platelet count of 21% (range 7%-67%) was observed during rhuGM-CSF treatment prior to the start of the apheresis procedures. Six patients were treated with a myeloablative conditioning therapy consisting of total body irradiation and/or high-dose polychemotherapy followed by autografting with blood stem cells. Five of them achieved a sustained engraftment. Recombinant human GM-CSF proved to be highly efficient in increasing the number of circulating progenitor cells in these patients with severely compromised hemopoiesis. Blood stem cells harvested under a rhuGM-CSF treatment are capable of restoring hemopoiesis in man after a myeloablative pretransplant therapy.

Adolescent↗
PubMed1989

Disease-free survival after autologous bone marrow transplantation in patients with acute myelogenous leukemia.

Autologous bone marrow transplantation (ABMT) makes it possible to escalate the dose of cytotoxic treatment to a lethal range. Disease-free survival (DFS) following myeloablative therapy and ABMT has been shown to be superior to conventional treatment in high risk patients with acute myelogenous leukemia (AML). It was the purpose of the present study to compare hematopoietic reconstitution, actuarial DFS, and relapse rate of patients transplanted in first complete remission (CR) of AML with those in second or subsequent CR, and to evaluate transplant related mortality. Fifty-two patients with AML, 22 in first CR (low risk) and 30 in second or subsequent CR (high risk), underwent total body irradiation (12.1 to 16.7 Gy) and cyclophosphamide (CY) treatment (200 mg/kg) followed by ABMT. The autograft was incubated with the active CY derivative Mafosfamide (ASTA Werke, Bielefeld, Federal Republic of Germany) to reduce the number of possibly contaminating clonogenic tumor cells. All patients showed three lineage engraftments with platelet recovery observed as being the slowest. The transplant related death rate was low at 5.8%. There was no significant difference in the kinetics of polymorphonuclear (PMN) cell or platelet reconstitution between the low and high risk patient subgroups. The estimated probability of DFS (relapse) after ABMT in first CR was 61% (36%) compared with 34% (65%) in second or subsequent CR, the longest follow-up being 55 months and 57 months, respectively (median follow-up 31 months and 19 months, respectively). ABMT offers a stable long-term DFS when performed in first CR with no relapses occurring in over a year after transplantation. Six later relapses, however, were seen after ABMT in second or subsequent CR, although DFS was not statistically different from that of first remission patients (P = .72).

Adult↗
PubMed1989

Enzyme activities of leukemic cells and biochemical changes induced by deoxycoformycin in vitro--lack of correlation with clinical response.

Deoxycoformycin (DCF) is a specific inhibitor of adenosine deaminase (ADA) and has been shown to be active in lymphoid neoplasms. Cytotoxicity is thought to be mediated by the accumulation of deoxyadenosine (AdR) and deoxyadenosine triphosphate (dATP) which inhibits ribonucleotide reductase and DNA synthesis in rapidly proliferating cells. Others suggested mechanisms leading to cell death particularly in non-dividing cells include depletion of ATP and NAD pools, inhibition of S-adenosylhomocysteine (SAH) hydrolase and induction of DNA strand breaks. In patients with high leukemic counts who were subsequently treated with DCF, we have studied (a) the levels of ADA, ecto-5'-nucleotidase (5NT), deoxyadenosine kinase (AdR-kinase) and SAH-hydrolase in the leukemic cells; [b) the in-vitro effects of DCF on dATP, ATP, NAD, SAH-hydrolase levels and on DNA strand breaks; and (c) the correlation between these parameters with clinical response to DCF. No significant difference in ADA, 5NT, AdR-kinase and SAH-hydrolase activities could be found between responders and non-responders. Incubation of the leukemic cells in vitro with DCF caused an inhibition of ADA, an accumulation of dATP, a moderate reduction in ATP and NAD levels, a suppression of SAH-hydrolase activity and an increase in DNA strand breaks in practically all the leukemic samples, irrespective of clinical response. Our results show that neither measurement of these enzymes nor studies of these biochemical sequelae of ADA inhibition in vitro predicts clinical responsiveness to DCF therapy.

Adenosine Deaminase Inhibitors↗
PubMed1989

[NMR tomographic imaging of bone marrow infiltrates in malignant lymphoma].

10 normals and 37 patients with Hodgkins' and non-Hodgkin's lymphoma were examined by MRT as part of a prospective study (lumbar spine, pelvis, proximal femora). In about half the patients the MR images showed diffuse or focal areas of reduced signal intensity in the bone marrow. The observation of reduced signal areas corresponded with the pathological findings from iliac crest biopsies. To improve diagnostic accuracy, the signal intensity from a chosen region of interest was related quantitatively to a standard level.

Adult↗