Rainer Haas

Risk-adapted postremission therapy in acute myeloid leukemia: results of the german multicenter AML HD93 treatment trial

The objective of the AML HD93 treatment trial was to evaluate the outcome in young adults with acute myeloid leukemia (AML) after postremission therapy was stratified according to cytogenetically defined risk. The rationales for the study design were based (i) on previous favorable results with high-dose cytarabine in AML with t(8;21), inv/t(16q22) and in AML with normal karyotype, and ii) on encouraging results obtained in several phase II trials using autologous stem cell transplantation (SCT). Between July 1993 and January 1998, 223 eligible patients, 16–60 years of age with newly diagnosed AML other than French–American–British type M3/M3v, were entered into the trial. Risk groups were defined as follows: low risk: t(8;21) or inv/t(16q22); intermediate risk: normal karyotype; high risk: all other chromosomal abnormalities. Following intensive double induction therapy with idarubicin, cytarabine and etoposide, all patients in complete remission (CR) received a first consolidation therapy with high-dose cytarabine and mitoxantrone (HAM). A second consolidation therapy was stratified according to the risk group: low risk: HAM; intermediate risk: related allogeneic SCT or sequential HAM; high risk: related allogeneic or autologous SCT. Double induction therapy resulted in a high CR rate of 74.5%, and 90% of the responding patients were eligible for consolidation therapy. Survival for all 223 trial entrants was 40%, and for the 166 patients who entered CR, disease-free (DFS) and overall survival were 40 and 51% after 5 years, respectively. Within the low-, intermediate- and high-risk groups, DFS and survival after 5 years were 62.5 and 87, 40 and 49 and 17 and 26% respectively, without advantage for allogeneic transplantation in the intermediate- and high-risk groups. Postremission therapy-related mortality was 0, 7 and 14%, respectively. This study demonstrates the feasibility of cytogenetically defined risk-adapted consolidation therapy. The overall trial results are at least equivalent to those of published trials supporting the risk-adapted treatment strategy.

In vivo depletion of B cells using a combination of high‐dose cytosine arabinoside/mitoxantrone and rituximab for autografting in patients with non‐Hodgkin's lymphoma

We performed a pilot study including rituximab (Mabthera; IDEC‐C2B8, Hoffmann‐La Roche) with a sequential high‐dose therapy protocol in 15 patients with follicular and three patients with mantle cell lymphoma and studied the potential of the chemoimmunotherapy to induce depletion of malignant B cells in vivo. Our treatment protocol included induction with three cycles of CHOP (cyclophosphamide, doxorubicin, vincristine and prednisone) chemotherapy, followed by peripheral blood stem cell (PBSC) mobilization using high‐dose cytosine arabinoside (2 g/m2 every 12 h, days 1 and 2) and mitoxantrone (10 mg/m2, days 2 and 3) (HAM), preceeded by rituximab (375 mg/m2). The proportion of CD19+ B cells in blood and bone marrow decreased from 1·2 ± 0·4% to 0·13 ± 0·1% (P = 0·01) and from 2·7 ± 0·8% to 0·8 ± 0·5% (P = 0·03) respectively. The number of t(14;18)‐positive cells in blood and bone marrow progressively decreased with treatment, as assessed by the quantitative real‐time PCR assay in four patients. Conversion to PCR‐negativity was achieved in the peripheral blood (PB) of seven informative patients. Leucaphereses were performed during the granulocyte colony‐stimulating factor (G‐CSF)‐supported leucocyte recovery phase. In 17 of 18 patients, a median of 15·1 × 106 CD34+ cells/kg body weight (BW) could be harvested by a single procedure for enrichment by an immunomagnetic method. Leucapheresis products contained 51·3 ± 28·8 × 104 CD19+ B cells/kg BW (mean) and were t(14;18) PCR negative in all seven informative patients. These data compare favourably with results obtained in patients treated with the same regimen without rituximab. The high‐dose therapy (n = 12 patients), including total body irradiation (14·4 Gy) and cyclophosphamide (200 mg/kg BW), was also preceeded by rituximab. Recovery of neutrophils to > 0·5 × 109/l and of platelets to > 20 × 109/l required a median of 13·5 and 11·5 d (range 11–24 and 9–24 d) respectively. In conclusion, the addition of the CD20 antibody to chemotherapy ensured tumour depletion in vivo and allowed the collection of PBSCs devoid of tumour cells and with conserved engraftment capability.

Factors influencing collection of peripheral blood progenitor cells following high‐dose cyclophosphamide and granulocyte colony‐stimulating factor in patients with multiple myeloma

We treated 103 multiple myeloma (MM) patients with 7 g/m2 cyclophosphamide (Cy) followed by 300 μg G‐CSF/d to harvest peripheral blood progenitor cells (PBPC). PBPC autografts containing > 2.0 × 106 CD34+ cells per kg body weight were obtained at the first attempt from 90/100 evaluable patients. The most significant factor predicting impairment of PBPC collection was the duration of previous melphalan treatment (P < 0.0001). In multivariate discriminate analysis, treatment with melphalan during the most recent chemotherapy cycles prior to mobilization (P = 0.0727) and previous radiotherapy (P = 0.0628) had a marginally significant negative influence on the efficacy of PBPC collection. We found no reduced functional capacity of CD34+ cells to restore haemopoiesis after myeloablative treatment related to the duration of melphalan exposure. At the time of best response to conventional treatment, a median paraprotein reduction of 21% was achieved following high‐dose cyclophosphamide (HD‐Cy). Two heavily pretreated patients died and one patient developed pulmonary toxicity W.H.O. grade IV following HD‐Cy. Potential transplant candidates should undergo mobilization and harvesting of PBPC before melphalan‐containing treatment. Combinations of haemopoietic growth factors and their dose modifications should be investigated to improve PBPC collection, to allow a dosage reduction of the mobilization chemotherapy.

Prevention of catheter-related infections by silver coated central venous catheters in oncological patients

Catheter-related infection (CRI) is a serious complication of central venous catheterization. We have investigated the efficacy of a silver-coated polyurethane catheter (Pellethane, Fresenius AG, Germany) in preventing CRI in oncological patients receiving chemotherapy in a phase II study. From November 1992 through April 1994, 266 patients were assigned to receive single lumen catheters, either standard uncoated catheters (UC, n = 113) or silver-coated ones (SC, n = 120). Catheters were inserted into the internal jugular vein after institutional approval and informed consent. Duration of catheterization (UC vs. SC = 13.3 vs. 12.7 days) and leukopenia (< 1.0 x 10(9) WBC/l; 4.3 vs. 3.6 days) were similar in both groups demonstrating a comparable risk for infections. Skin reactions at the catheter entry site were recorded daily. CRI and colonization rates were studied by semiquantitatively culturing intradermal and intravascular segments. CRI were confirmed by blood cultures obtained via catheter and from peripheral veins in cases of suspected sepsis or at the end of catheterization. No adverse effects from the silver-coated catheter could be observed. The bacteriological results showed that SC were colonized (> 15 CFU) in 45.1% and UC in 44.2%. CRI developed in 21.2% of the UC patients but only in 10.2% of the SC patients (p = 0.011). We conclude that this new silver-coated central venous catheter is biocompatible and effective in reducing the incidence of catheter-related infections in oncological patients.

Autografting with CD34+ peripheral blood stem cells: retained engraftment capability and reduced tumour cell content

The efficacy of an immunomagnetic purging method and the Isolex 300 devices were assessed for selecting CD34+ cells from leukapheresis products of 29 patients with non‐Hodgkins lymphoma (NHL), 39 with multiple myeloma and 34 with breast cancer. The mean purity of the CD34+ cell population was 93.6% and the mean recovery was 67.7%. Following enzymatic cleavage by chymopapain the expression of Thy‐1 and Leu‐8 was significantly reduced without affecting haematological recovery. The population of selected CD34+ cells of 4/8 patients with follicular lymphoma became PCR‐negative. A 2.5 log reduction of tumour cells could be achieved in four patients with multiple myeloma as shown by a quantitative PCR assay. There were no tumour cells detectable in any of the 19 CD34+ cell preparations of patients with breast cancer. In 64 patients who received 94 cycles of high‐dose therapy, a mean number of 4.7 × 106 CD34+ cells/kg were autografted. The time needed for platelet reconstitution was different when a comparison was made with 156 patients, who had received unmanipulated leukapheresis products (10 v 12 d, P = 0.006). No significant differences with regard to neutrophil recovery were noted. Five patients had a graft failure. Two of them died (on day 78 and 88 following PBSCT), and three patients were rescued with unmanipulated back‐up transplants. In conclusion, the immunomagnetic selection of CD34+ cells provides autografts with reduced tumour cell content and an engraftment ability similar to that of unmanipulated autografts.

Immunomagnetic selection of CD34+ peripheral blood stem cells for autografting in patients with breast cancer

Contamination of transplants with tumour cells may contribute to relapse after peripheral blood stem cell transplantation (PBSCT). We studied the feasibility of CD34+ cell selection from blood‐derived autografts obtained following G‐CSF‐supported cytotoxic chemotherapy in a group of 25 patients with breast cancer (10 with high‐risk stage II/III and 15 with stage IV without bone or bone marrow involvement).

Neurobehavioral toxicity of total body irradiation: a follow-up in long-term survivors

PURPOSE Total body irradiation (TBI) in preparation for bone marrow transplantation (BMT) is a routine treatment of hematological malignancy. A retrospective and a prospective group study of long-term cerebral side effects was performed, with a special emphasis on neurobehavioral toxicity effects. METHODS AND MATERIALS Twenty disease-free patients treated with hyperfractionated TBI (14.4 Gy, 12 x 1.2 Gy, 4 days), 50 mg/kg cyclophosphamide, and autologous BMT (mean age 38 years, range 17-52 years; age at TBI 35 years, 16-50 years; follow-up time 32 months, 9-65 months) participated in a neuropsychological, neuroradiological, and neurological examination. Data were compared to 14 patients who were investigated prior to TBI. Eleven patients with renal insufficiencies matched for sex and age (38 years, 20-52 years) served as controls. In a longitudinal approach, neuropsychological follow-up data were assessed in 12 long-term survivors (45 years, 23-59 years; follow-up time 8.8 years, 7-10.8 years; time since diagnosis 10.1 years, 7.5-14.2 years). RESULTS No evidence of neurological deficits was found in post-TBI patients except one case of peripheral movement disorder of unknown origin. Some patients showed moderate brain atrophy. Neuropsychological assessment showed a subtle reduction of memory performance of about one standard deviation. Cognitive decline in individual patients appeared to be associated with pretreatment (brain irradiation, intrathecal methotrexate). Ten-years post disease onset, survivors without pretreatment showed behavioral improvement up to the premorbid level. CONCLUSION The incidence of long-term neurobehavioral toxicity was very low for the present TBI/BMT regimen.

Peripheral blood progenitor cell (PBPC) counts during steady-state haemopoiesis enable the estimation of the yield of mobilized PBPC after granulocyte colony-stimulating factor supported cytotoxic chemotherapy: an update on 100 patients

Peripheral blood progenitor cells (PBPC) can be mobilized using chemotherapy and granulocyte colony‐stimulating factor (G‐CSF). We and others previously reported a correlation of steady‐state PBPC counts and the PBPC yield during mobilization in a small group of patients. Here we present data on 100 patients (patients: 25 non‐Hodgkins lymphoma (NHL), five Hodgkins disease, 35 multiple myeloma (MM), 35 solid tumour) which enabled a detailed analysis of determinants of steady‐state PBPC levels and of mobilization efficiency in patient subgroups. Previous irradiation (P = 0.0034) or previous chemotherapy in patients with haematological malignancies (P = 0.0062) led to a depletion of steady‐state PB CD34+ cells. A correlation analysis showed steady‐state PB CD34+ cells (all patients: r = 0.52, P < 0.0001; NHL patients, r = 0.69, P = 0.0003; MM patients: r = 0.66, P = 0.0001) and PB colony‐forming cells can reliably assess the CD34+ cell yield in mobilized PB. In patients with solid tumour a similar trend was observed in mobilization after the first chemotherapy cycle (r = 0.51, P = 0.05) but not if mobilization occurred after the second or further cycle of a sequential dose‐intensified G‐CSF‐supported chemotherapy regimen, when premobilization CD34+ counts were 18‐fold elevated (P = 0.004). When the patients with MM (r = 0.63, P = 0.0008) or with NHL (r = 0.65, P = 0.006) were analysed separately, a highly significant correlation of the steady‐state PB CD34+ cell count to the mean leukapheresis CD34+ cell yield was found, whereas no correlation was observed for patients with a solid tumour. For patients with haematological malignancies estimates could be calculated which, at a specific steady‐state PB CD34+ cell count, could predict with a 95% probability a defined minimum progenitor cell yield. These results enable recognition of patients who mobilize PBPC poorly and may assist selection of patients for novel mobilization regimens.

The human immunodeficiency virus (HIV)-type 1 coreceptor CXCR-4 (fusin) is preferentially expressed on the more immature CD34+ hematopoietic stem cells

Abstract In synergy with the CD4 antigen, the chemokine receptor CXCR-4 functions as a coreceptor for T-cell-tropic HIV-1 strains. Using two- and three-color immunofluorescence analysis, we examined the expression of CXCR-4 on CD34+ cells in 21 samples obtained from leukapheresis (LP) products of cancer patients who underwent G-CSF-supported cytotoxic chemotherapy. In addition, eight samples from bone marrow (BM) were obtained. CXCR-4 was expressed on the surface of CD34+ cells from samples of both hematopoietic sources. The mean proportion of CD34+/CXCR-4+ cells from LP products was 1.7-fold greater in comparison with those from bone marrow (65.9±4.1% vs. 37.5±8.6% [±SEM], p<0.05). For an intraindividual comparison, LP products and bone marrow from six patients were obtained on the same day, confirming the significantly greater proportion of CD34 + cells coexpressing CXCR-4 cells in LP products. In order to examine whether the CXCR-4 expression was related to the stage of maturation and differentiation of CD34+ cells, six samples from LP products and four samples from bone marrow were assessed using three-color immunofluorescence analysis. We found that the subset of CD34+/CD38low and CD34+/HLA-DRlow cells representing a population of more immature progenitor cells were brightly positive for CXCR-4, while there was a decrease in the level of CXCR-4 expression in the population of CD34+/HLA-DRbright and CD34+/CD38bright cells. Based on the assessment of ten LP products, we found that the mean proportion of CD34+ cells coexpressing CD4 and CXCR-4 was 6.2±2.3% [±SEM], suggesting that a small population of CD34+ cells are, in principle, susceptible for an infection with T-cell-tropic HIV-1 strains. In conclusion, our data suggest that CXCR-4 is present on the surface of hematopoietic progenitor cells – particularly more primitive CD34+ cells. CXCR-4 could play a role in the homing of CD34+ cells to stromal elements of the bone marrow via its natural ligand stromal-derived factor-1 (SDF-1).

Cataract incidence after total-body irradiation

PURPOSE The aim of this retrospective study was to evaluate cataract incidence in a homogeneously-treated group of patients after total-body irradiation (TBI) followed by autologous bone marrow transplantation or peripheral blood stem cell transplantation. METHODS AND MATERIALS Between 1982 and 1994, a total of 260 patients received either autologous bone marrow or blood stem cell transplantation for hematological malignancy at the University of Heidelberg. Two hundred nine of these patients received TBI in our hospital. Radiotherapy was applied as hyperfractionated TBI, with a median dose of 14.4 Gy in 12 fractions over 4 days. Minimum time between fractions was 4 h. Photons with an energy of 23 MeV were used with a dose rate of 7-18 cGy/min. Ninety-six of the 209 irradiated patients were still alive in 1996; 86 of these patients (52 men, 33 women) answered a questionnaire and could be examined ophthalmologically. The median age at time of TBI was 38.5 years, with a range of 15-59 years. RESULTS The median follow-up is now 5.8 years, with a range of 1.7-13 years. Cataract occurred in 28/85 patients (32.9%) after a median of 47 months (1-104 months). In 6 of 28 patients who developed a cataract, surgery of the cataract was performed. Whole-brain irradiation prior to TBI had been performed more often in the group of patients developing cataract (14.3%) versus 10.7% in the group of patients without cataract. However, there was no statistical difference (Chi-square, p>0.05). CONCLUSION Cataract is a common side effect of TBI. Cataract incidence found in our patients is comparable to results of other centers using a fractionated regimen for TBI. To assess the incidence of cataract after TBI, a long-term follow-up is required.