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Featured researches published by Ar Zander.


Bone Marrow Transplantation | 1999

Early infections in patients undergoing bone marrow or blood stem cell transplantation--a 7 year single centre investigation of 409 cases.

William Krüger; Bettina Rüssmann; Nicolaus Kröger; Salomon C; Ekopf N; Elsner Ha; Kaulfers Pm; Mack D; N Fuchs; M Dürken; H Kabisch; R Erttmann; Ar Zander

Infections are a major cause of morbidity and mortality in patients undergoing high-dose therapy and subsequent autologous or allogeneic haemopoietic stem cell transplantation, despite the change from topical to systemic anti-infection prophylaxis and the introduction of growth factors and new antimicrobial drugs. We report our single centre experience with data from 409 patients treated at our unit from its opening in 1990 until May 1997. Three hundred and seventy-eight patients were transplanted for the first time, 12 patients were retransplanted or boosted and 19 patients were readmitted for miscellaneous reasons. 245 patients were allografted and 157 autografted. Antimicrobial prophylaxis was mainly quinolones, fluconazole plus amphotericin-B orally, aciclovir, and TMP/SMX or pentamidine. Three hundred and nineteen (78%) developed fever of significantly longer duration in the allogeneic setting with anti-CMV seropositivity. The most frequent infection was fever of unknown origin (50.6%), followed by septicaemia (12.5%) and pneumonia (11.0%). Pathogens isolated in 24.6% of the infections were mostly gram- positive bacteria (57.9%), followed by non-fermenting rods (11.2%), Aspergillus spp. and Candida spp. (10.3%, each). Cumulative response rate to antimicrobial therapy was 66.9%. Infections were responsible for 62.5% (25/40) of deaths after transplantation. Predominant pathogens were Aspergillus spp. (11), Candida spp. (four), and Pseudomonas spp. (three). None of the patients died from gram-positive bacterial infection. The risk of dying from infection was 11.2% after allografting and 0.8% after autotransplantation. Infections remain a major risk for early death after allogeneic transplantation of haemopoietic stem cells. Infection with gram-negative bacteria can be prevented by quinolone prophylaxis. Predominant pathogens are Aspergillus spp. Candida spp. and nonfermenting rods. Systemic infection with these pathogens is associated with a poor prognosis. Antimycotic prophylaxis and the therapy must be improved.


Bone Marrow Transplantation | 2006

Comparable results in patients with acute lymphoblastic leukemia after related and unrelated stem cell transplantation

J Dahlke; N Kröger; Tatjana Zabelina; F Ayuk; N Fehse; Christine Wolschke; O Waschke; Heike Schieder; Helmut Renges; William Krüger; A Kruell; A Hinke; R Erttmann; H Kabisch; Ar Zander

We report the results of 84 patients with ALL after related (n=46) or unrelated (n=38) allogeneic SCT. Mean recipient age was 23 years (range: 1–60) and median follow-up was 18 months (range: 1–133). Forty-three patients were transplanted in CR1; 25 in CR2 or CR3; four were primary refractory; four in PR; eight in relapse. The conditioning regimen consisted of TBI/VP16/CY (n=76), TBI/VP16 (n=2), TBI/CY (n=2), Bu/VP16/CY (n=4). The OS at 3 years was 45% (44% unrelated, 46% related). Univariate analysis showed a significantly better OS for patients <18 years (P=0.03), mismatched sex-combination (P=0.03), both with a stronger effect on increasing OS after unrelated SCT. Factors decreasing TRM were patient age <18 years (P=0.004), patient CMV-seronegativity (P=0.014), female recipient (P=0.04). There was no significant difference in TRM and the relapse rate was similar in both donor type groups. Multivariate analysis showed that factors for increased OS which remained significant were mismatched sex-combination (RR: 0.70,95% CI: 0.51–0.93, P=0.015), patient age < 18 years (RR: 0.66, 95% CI: 0.47–0.93, P=0.016). A decreased TRM was found for female patients (RR: 0.56, 95% CI: 0.33–0.98, P=0.042), negative CMV status of the patient (RR: 0.57, 95% CI: 0.36–0.90, P=0.015). Unrelated stem cell transplantation for high-risk ALL patients with no HLA-compatible family donor is justifiable.


Bone Marrow Transplantation | 2002

In vivo T cell depletion with pretransplant anti-thymocyte globulin reduces graft-versus-host disease without increasing relapse in good risk myeloid leukemia patients after stem cell transplantation from matched related donors

N Kröger; Tatjana Zabelina; William Krüger; Helmut Renges; N Stute; J Rischewski; S Sonnenberg; Francis Ayuk; F Tögel; U Schade; H Fiegel; R Erttmann; C Löliger; Ar Zander

One-hundred and two patients with good risk myeloid leukemia (CML first chronic phase or AML first CR) were transplanted from HLA-related donors after conditioning with (n = 45) or without anti-thymocyte globulin (ATG) (n = 57). One graft failure was observed in the non-ATG and none in the ATG group. The median time to leukocyte engraftment (>1 × 109/l) was 16 (range 12–33) in the ATG group and 17 days (range 11–29) in the non-ATG group (NS) and for platelet engraftment (>20 × 109/l) 24 and 19 days (P = 0.002), respectively. Acute GVHD grade II–IV was observed in 47% of the non-ATG and in 20% of the ATG group (P = 0.004). Grade III/IV GVHD occurred in 7% of the ATG and in 32% of the non-ATG group (P = 0.002). Chronic GVHD was seen in 36% and 67% (P = 0.005), respectively. After a median follow-up of 48 months (range 2–128), the 5-year estimated OS is 66% (95% KI: 51–81%) for the ATG group and 59% (95% KI: 46–72%) for the non-ATG group (NS). The 5-year estimated DFS is 64% (95% KI: 50–78%) for ATG and 55% (95% KI: 43–67%) for the non-ATG regimen (NS). The 5-year probability of relapse was 5% in the ATG and 15% in the non-ATG group (NS). ATG as part of the conditioning regimen leads to a significant reduction in GVHD without increase of relapse in patients with myeloid leukemia after stem cell transplantation from HLA-related donors.


Bone Marrow Transplantation | 1999

Use of a five-agent GVHD prevention regimen in recipients of unrelated donor marrow

Ar Zander; T Zabelina; Nicolaus Kröger; Helmut Renges; William Krüger; C Löliger; M Dürken; Marcus Stockschläder; M de Wit; G Wacker-Backhaus; S Bielack; N Jaburg; Bettina Rüssmann; R Erttmann; H Kabisch

A five-agent GVHD prophylaxis programme consisting of cyclosporin A, methotrexate, anti-thymocyte-globulin, pentaglobin and metronidazol was given to 48 recipients of unrelated donor marrow with chronic myelogenous leukemia, acute leukemia, myelodysplastic syndromes, and familiar lymphocytic hemophagocytosis of an average age of 33.5 (0.6–56) years. GVHD grades II–IV occurred in 18 patients (39%) and grades III–IV in five patients (11%). Chronic GVHD developed in nine patients (23%), three limited and six extensive. Fifteen patients died. Clinical relapse was detected in eight patients. Four patients died as a consequence of the underlying disease and subsequent treatment, 11 patients died of transplant-related causes. After a median follow-up of 19 months, the overall and disease-free survival are 67% and 62%, respectively. Survival by age is as follows: 0–19 years: 12/13 patients; 20–39 years: 14/25 patients; 40–59 years: 7/10 patients. The five-agent GVHD prophylaxis regimen is effective. Matched-unrelated donor transplants can be carried out safely in patients younger than 50 years of age. The results in patients younger than 20 years of age should encourage matched-unrelated donor transplants at earlier stages of the disease.


Bone Marrow Transplantation | 2001

A fludarabine-based dose-reduced conditioning regimen followed by allogeneic stem cell transplantation from related or unrelated donors in patients with myelodysplastic syndrome.

N Kröger; Johannes Schetelig; Tatjana Zabelina; William Krüger; Helmut Renges; N Stute; J Schrum; H Kabisch; W Siegert; Ar Zander

We investigated the feasibility and efficacy of a fludarabine-based dose-reduced conditioning regimen followed by stem cell transplantation from related (n = 5) or unrelated HLA-matched donors (n = 7) in 12 patients with high risk MDS, who were not eligible for a standard myeloablative conditioning regimen. The conditioning regimen consisted of fludarabine 30 mg/m2 daily for 6 days, busulfan 4 mg/kg daily for 2 days and anti-thymocyte globulin (ATG, rabbit) 10 mg/kg daily for 4 days in 11 patients, while one patient received fludarabine, ATG, cyclophosphamide and thiotepa. Graft-versus-host disease prophylaxis consisted of cyclosporine and a short course of methotrexate. The median age of the patients was 53 years (range 37–59). The median percentage of blasts in bone marrow aspirate at transplantation was 15% (range <5% to 35%). Diagnosis at transplant was RA (n = 1), RAEB (n = 5), RAEB-T (n = 5) and sAML (n = 1). A complex karyotype including monosomy 7 was noted in five patients. The reasons for using a dose-reduced conditioning regimen were prior autologous/syngeneic BMT (n = 4), active fungal infection (n = 2) or age/reduced performance status (n = 6). Engraftment was observed in all patients with complete donor chimerism. The incidence of acute GVHD (grade II–IV) was 33%. Eight patients died during follow-up due to relapse (n = 4), liver toxicity (n = 2), aspergillus (n = 1) or aGVHD grade IV (n = 1). After a median follow-up of 19 months, the 2-year estimated disease-free survival is 12% (95% CI: 2–23%) and the overall survival is 26% (95% CI: 4–52%). Fludarabine dose-reduced conditioning prior to allogeneic stem cell transplantation in high risk MDS patients, who were not eligible for standard transplantation, resulted in stable engraftment with complete chimerism, but the toxicity and relapse rate were considerable. Bone Marrow Transplantation (2001) 28, 643–647.


Bone Marrow Transplantation | 1998

Long-term disease-free survival of patients with advanced mantle-cell lymphoma following high-dose chemotherapy

Nicolaus Kröger; M Hoffknecht; Peter Dreger; William Krüger; Zeller W; Krüll A; Marcus Stockschläder; Bittner S; H. J. Weh; Ar Zander

In advanced stage mantle cell lymphoma, conventional chemotherapy yields a complete remission rate below 40%, and the median survival rate is only about 3 years. Between 1991 and 1996 we treated nine such patients (six male; three female) with high-dose chemotherapy (six of these also with 12 Gy fractionated total body irradiation (TBI)) and peripheral stem cell support (n = 8) or allogeneic bone marrow transplantation (n = 1). The median age was 47 years (range, 28–61). At the time of high-dose chemotherapy, five patients were in first complete remission (CR), two in first partial remission (PR) and two in second remission (CR = 1; PR = 1). High-dose chemotherapy included TBI (12 Gy), etoposide and cyclophosphamide (patients 1–5), TBI and cyclophosphamide (patient 7), busulfan, etoposide and cyclophosphamide (patients 6 and 9), cyclophosphamide and busulfan (patient 8). The patterns of toxicity according to the Bearman score were usually mild (mucositis grade 2, n = 7; renal grade I, n = 2) with no therapy-related fatality. Only one patient developed hepatic toxicity grade III (veno-occlusive disease) but recovered completely. The median time to neutrophil engraftment was 10 days (range, 8–15). After high-dose chemotherapy all patients achieved complete remission. After a median follow-up of 22 months (range, 9.4–64) all patients remain in continuous complete remission. These encouraging results suggest that high-dose chemotherapy can be applied safely and leads to long-term disease-free survival in otherwise incurable disease.


Bone Marrow Transplantation | 2001

Comparison of total body irradiation vs busulfan in combination with cyclophosphamide as conditioning for unrelated stem cell transplantation in CML patients.

N Kröger; Tatjana Zabelina; William Krüger; Helmut Renges; N Stute; H Kabisch; N Jaburg; C Löliger; Andreas Krüll; Ar Zander

We compared fractionated total body irradiation (12 Gy)/cyclophosphamide (120 mg/kg) with busulfan (16 mg/kg)/cyclophosphamide (120 mg/kg) as preparative therapy in unrelated donor stem cell transplantation of CML patients. Fifty patients with CML (1.CP = 46; aP = 4) and a median age of 36 years (range 16–52) were enrolled in this sequential trial between 1994 and 1999. In both groups patients were well balanced with respect to age, disease status, stem cell source and CMV status. All patients received standard doses of cyclosporin A, methotrexate and anti-thymocyte globulin (ATG) as GVHD prophylaxis. No graft failures occurred in either group. The median day of leukocyte engraftment was earlier in the Bu/Cy than in the TBI/Cy group (day 15 vs 17; P = 0.006). The incidence of grade II–IV GVHD was 40% in the TBI/Cy and 36% in the Bu/Cy group, whereas severe grade III/IV GVHD was only observed in 12% of patients in both groups. The incidence of chronic GVHD (limited and extensive) at 1 year was higher in the Bu/Cy arm (65% vs 30%; P = 0.02). More toxicity grade I/II of the liver (88% vs 44%; P = 0.002) and more hemorrhagic cystitis (32% vs 8%; P = 0.02) were observed in the Bu/Cy regimen. Seven relapses in the TBI and no relapse in the Bu/Cy group were observed after a median follow-up of 44 and 15 months, respectively. The estimated 3 year OS and DFS was 72% (95% CI: 55–98%) and 58% (95% CI: 39–77%) in the TBI and 70% (95% CI: 51–89%) for DFS and OS in the Bu/Cy group. We conclude that the anti-leukemic effect of the Bu/Cy regimen seems to be at least as effective as the TBI/Cy combination in unrelated stem cell transplantation of CML patients, with no graft failures, but that it correlates with a higher incidence of liver toxicity, hemorrhagic cystitis and chronic GVHD. Longer follow-up is necessary to determine the late relapse rate and late toxicity. Bone Marrow Transplantation (2001) 27, 349–354.


Bone Marrow Transplantation | 1999

Stem cell mobilization with G-CSF alone in breast cancer patients: higher progenitor cell yield by delivering divided doses (2 × 5 μg/kg) compared to a single dose (1 × 10 μg/kg)

N Kröger; W Zeller; Ht Hassan; William Krüger; Kai Gutensohn; Löliger C; Ar Zander

We investigated the schedule dependency of G-CSF (10 μg/kg) alone in mobilizing peripheral blood progenitor cells (PBPC) in breast cancer patients. After a median of three cycles (range, 2–6) of anthracycline-based chemotherapy, 49 patients with breast cancer (stage II/III, ⩾10+ Ln n = 36; locally advanced/ inflammatory n = 8, stage IV (NED) n = 5) underwent PBPC collection after steady-state mobilization either with 1 × 10 μg/kg (n = 27) or with 2 × 5 μg/kg (n = 22) G-CSF daily for 4 consecutive days until completion of apheresis. Apheresis was started on day 5. Priming with 2 × 5 μg/kg resulted in a higher median number of CD34+ cells (5.8 vs 1.9 × 106/kg, P = 0.003), MNC (6.6 vs 2.6 × 108/kg, P < 0.001) and cfu-gm (6.5 vs 1.3 × 104/kg, P = 0.001) in the first apheresis than with 1 × 10 μg/kg. Also the overall number of collected BFU-E was higher in the 2 × 5 μg group (9.2 vs 3.1 × 104/kg; P = 0.01). After high-dose chemotherapy with cyclophosphamide/thiotepa/mitoxantrone (n = 46) hematopoietic engraftment with leukocyte count >1.0/nl was reached in both groups after a median of 10 days (range, 8–15) and with platelets count >50/nl after 12 (range, 9–40) and 13 days (range, 12–41), respectively. A threshold of >2.5 × 106/kg reinfused CD34+ cells ensured rapid platelet engraftment (12 vs 17 days; P = 0.12). Therefore, the target of collecting >2.5 × 106 CD34+ cells was achieved in 21/27 (80%) patients of the 1 × 10 μg group and in 21/22 (95%) patients of the 2 × 5 μg/kg group with a median of two aphereses (range, 1–4). None in the 10 μg/kg group, but 6/22 (28%) patients in the 2 × 5 μg/kg group required only one apheresis procedure, resulting in fewer apheresis procedures in the 2 × 5 μg/kg group (mean, 1.8 vs 2.3, P = 0.01). These results demonstrate that priming with 10 μg/kg G-CSF alone is well tolerated and effective in mobilizing sufficient numbers of CD34+ cells in breast cancer patients and provide prompt engraftment after CTM high-dose chemotherapy. G-CSF given 5 μg/kg twice daily (2 × 5 μg) leads to a higher harvest of CD34+ cells and required fewer apheresis procedures than when given 10 μg/kg once daily (1 × 10 μg).


Bone Marrow Transplantation | 1998

Busulfan, cyclophosphamide and etoposide as high-dose conditioning therapy in patients with malignant lymphoma and prior dose-limiting radiation therapy

Nicolaus Kröger; M Hoffknecht; Mathias Hänel; William Krüger; Zeller W; Marcus Stockschläder; M de Wit; H. J. Weh; H Kabisch; R Erttmann; Ar Zander

Relapse after transplant for malignant lymphomas remains the main cause of treatment failure. Most conditioning regimens contain total body irradiation (TBI). We investigated the toxicity and efficacy of an intensified chemotherapy conditioning regimen without TBI in patients with relapsed or high-risk malignant lymphoma who had received prior radiation therapy and were therefore not eligible for TBI. Twenty patients with a median age of 38 (18–56) and relapsed or high-risk malignant non-Hodgkin’s lymphoma (NHL, n = 16) or Hodgkin’s disease (HD, n = 4) underwent high-dose chemotherapy consisting of busulfan (16 mg/kg), cyclophosphamide (120 mg/kg) and etoposide 30 mg/kg (n = 8) or 45 mg/kg (n = 12) followed by peripheral stem cell support (n = 14), autologous bone marrow (n = 3), allogeneic (n = 2) or syngeneic (n = 1) transplantation. All but two had chemosensitive disease before high-dose chemotherapy. The main toxicity – according to the Bearman score – was mucositis II in 18 (90%) patients; five patients (25%) suffered a grade I hepatic toxicity. GI toxicity I occurred in three (15%) and renal toxicity I in two patients (10%). Sixty percent of the patients developed transient dermatitis with erythema and three of them (15%) had skin desquamation; one patient experienced asymptomatic pancreatitis. Toxicity was slightly higher in patients treated with 45 mg/kg etoposide. One patient (5%) died of treatment-related veno-occlusive disease. After a median follow-up of 50 months (24–84) the disease-free and overall survival were 50% and 55%. One of the nine relapsing patients developed secondary AML 18 months after transplant. High-dose busulfan, cyclophosphamide and etoposide is an effective regimen resulting in long-term disease-free survival in 50% of patients with relapsed malignant lymphoma and prior radiation therapy. The toxicity is moderate with a low treatment-related mortality (5%).


Bone Marrow Transplantation | 1998

Intensified conditioning regimen in bone marrow transplantation for Philadelphia chromosome-positive acute lymphoblastic leukemia

Nicolaus Kröger; William Krüger; G Wacker-Backhaus; S Hegewisch-Becker; Marcus Stockschläder; N Fuchs; Bettina Rüssmann; Helmut Renges; M Dürken; S Bielack; M de Wit; Gunter Schuch; H Bartels; D Braumann; R Kuse; H Kabisch; R Erttmann; Ar Zander

We investigated an intensified conditioning regimen including fractionated total body irradiation (12 Gy), etoposide (30–45 mg/kg) and cyclophosphamide (120 mg/kg), followed by autologous (n = 5), allo-related (n = 13) or allo-unrelated (n = 6) bone marrow (n = 22) or peripheral stem cell (n = 2) transplantation in patients with Philadelphia chromosome-positive acute lymphoblastic leukemia. One patient received busulfan (16 mg/kg) instead of TBI. Nineteen patients were transplanted in 1CR, two in 2CR, one in 1PR and two in relapse. Major toxicity was mucositis grade II according to the Bearman scale in all patients. The treatment-related mortality was 25%, mainly due to infection or GVHD after allogeneic transplantation. After a median follow-up of 45 months (range 2–93), nine patients (37.5%) remain alive in CR. Nine patients (37.5%) relapsed and eight (33.3%) of these subsequently died. After autologous transplantation, four of five patients (80%) relapsed and died. Late relapse was seen after allogeneic, as well as autologous transplantation, at 33 and 59 months, respectively. The Kaplan–Meier estimate of leukemia-free survival for all patients is 38% at 3 years (95% CI: 18–58%) and 35% at 5 years (95% CI: 15–55%). For allogeneic transplants in first CR (n = 15) the estimate of disease-free survival was 46% at 3 years (95% CI: 19–73%) and 34% at 5 years (95% CI: 17–51%). Patients aged below 30 years had a better estimated overall survival at 3 years (61% vs 11%, P < 0.001). the bcr-abl fusion transcript (p210 vs p190 vs p210/190) did not affect disease-free or overall survival. In our experience, an intensified conditioning regimen seems to improve the results of bone marrow transplantation in patients with Ph+ acute lymphoblastic leukemia. However, the high relapse rate warrants novel approaches to enhance anti-leukemic efficacy.

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N Kröger

University of Hamburg

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Dieter L. Munz

Humboldt University of Berlin

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Lilli Geworski

Humboldt University of Berlin

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Ray Valencia

Humboldt University of Berlin

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Sofiane Maza

Humboldt University of Berlin

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Erik Dräger

Humboldt University of Berlin

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