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K F Bradstock

Publications and source records attributed to K F Bradstock.

At least 19 recordsLinked to original sources

Generation of tumour-specific cytotoxic T-cell clones from histocompatibility leucocyte antigen-identical siblings of patients with melanoma.

Lymphodepletion and infusion of autologous expanded tumour-infiltrating lymphocytes is effective therapy for patients with malignant melanoma. Antitumour responses are likely to be mediated by HLA class I- and II-restricted immune responses directed at tumour antigens. We assessed whether the peripheral blood of normal HLA-matched siblings of patients with melanoma could be used to generate lymphocytes with antimelanoma activity for adoptive immunotherapy after allogeneic blood or marrow transplantation. Melanoma cell lines were derived from two donors and were used to stimulate the mononuclear cells of three HLA-identical siblings. CD4(+) clones dominated cultures. Of these, approximately half were directly cytotoxic towards recipient melanoma cells and secreted interferon-gamma in response to tumour stimulation. More than half of the noncytotoxic clones also secreted interferon-gamma after melanoma stimulation. No CD4(+) clones responded to stimulation with recipient haemopoietic cells. The majority of CD8(+) clones directly lysed recipient melanoma, but did not persist in long-term culture in vitro. No crossreactivity with recipient haemopoietic cells was observed. The antigenic target of one CD4(+) clone was determined to be an HLA-DR11-restricted MAGE-3 epitope. Antigenic targets of the remaining clones were not elucidated, but appeared to be restricted through a non-HLA-DR class II molecule. We conclude that the blood of allogeneic HLA-matched sibling donors contains melanoma-reactive lymphocyte precursors directed at tumour-associated antigens. Adoptive immunotherapy with unselected or ex vivo-stimulated donor lymphocytes after allogeneic stem cell transplantation has a rational basis for the treatment of malignant melanoma.

CD4-Positive T-Lymphocytes↗

Reduced-intensity allogeneic haemopoietic stem cell transplantation induces durable responses in patients with chronic B-lymphoproliferative disorders.

Thirty-six patients with chronic B-lymphoproliferative disorders (B-LPD) underwent reduced-intensity allogeneic transplantation (RIT) from HLA-identical related donors. Diagnoses included follicular (n=17), mantle cell (n=9) and small lymphocytic lymphoma (n=2), and chronic lymphocytic leukaemia (n=8). Median age at transplant was 51 years (range, 30-66) and time from diagnosis was 3.4 years (range, 0.3-9.5). At transplant, 28% were in CR, 36% were in PR and 36% were chemorefractory. Conditioning therapy included fludarabine and either cyclophosphamide (n=27) or melphalan (n=9). Graft-versus-host disease (GVHD) prophylaxis consisted of cyclosporin (CsA)/methotrexate (n=21), CsA/mycophenolate mofetil (n=13) or CsA alone (n=2). Eight patients died owing to acute GVHD (n=3), infection in association with chronic GVHD (n=4) and intra-abdominal bleeding (n=1). Treatment-related mortality was 8% at day 100, and 17 and 20% at one and two years, respectively. The cumulative incidence of grade II-IV acute GVHD was 58%, whereas limited and extensive chronic GVHD occurred in 25 and 56%, respectively. No patient has relapsed or progressed. At a median follow-up of 48 months, overall survival probability is 80% (95% CI, 67-93%). We confirm that RIT in chronic B-LPD can result in high and durable CR rates but with significant incidences of acute and chronic GVHD.

Adolescent↗

Fresh PBSC harvests, but not BM, show temperature-related loss of CD34 viability during storage and transport.

BACKGROUND: The optimum conditions for storage and transport of freshly harvested HPC in the liquid state are uncertain. It is not specified in commonly applied standards for stem cell transplantation. We used a viable CD34 assay to determine the optimum temperature for maintaining progenitor cell viability in freshly harvested BM and PBSC. Our aim was to identify standardized conditions for storage and transport of marrow or peripheral blood products that would optimize CD34 recovery, leading to better transplant outcomes. METHODS: Samples were aseptically removed from 46 fresh HPC harvests (34 PBSC and 12 BM) and stored at refrigerated temperature (2-8 degrees C), room temperature (18-24 degrees C) and 37 degrees C for up to 72 h. Samples were analyzed for viable CD34+ cells/microL at 0, 24, 48 and 72 h. RESULTS: The mean viable CD34+ yield prior to storage was 7.7 x 10(6)/kg (range 0.7-30.3). The mean loss of viable CD34+ cells in HPC products at refrigerated temperature was 9.4%, 19.4% and 28% at 24, 48 and 72 h, respectively. In contrast, the mean loss of viable CD34+ cells at room temperature was 21.9%, 30.7% and 43.3% at 24, 48 and 72 h, respectively. No viable CD34+ cells remained after storage at 37 degrees C for 24 h. Only PBSC products and not BM showed temperature-related loss of CD34 viability. Greater loss of viable CD34+ cells was observed for allogeneic PBSC compared with autologous PBSC. DISCUSSION: These results demonstrate that the optimum temperature for maintaining the viability of CD34+ cells, during overnight storage and transport of freshly harvested HPC, is 2-8 degrees C. These findings will allow the development of standard guidelines for HPC storage and transport.

Adult↗

Outpatient fractionated ifosfamide, carboplatin and etoposide as salvage therapy in relapsed and refractory non-Hodgkin's and Hodgkin's lymphoma.

We have treated 75 transplant-eligible patients with relapsed or refractory lymphoma using an outpatient-based fractionated regimen of ifosfamide, carboplatin and etoposide (ICE) for both salvage and stem cell mobilisation. Patients included DLBC (n = 33), follicular (n = 23), NK/T-cell (n = 3), mantle cell (n = 3) and Hodgkin's lymphoma (n = 13). Cycles of outpatient ICE were given every 21 days and consisted of: ifosfamide 5000 mg/m(2) i.v. fractionated into three equally divided doses and infused over 2-3 h on days 1-3, carboplatin (mg dose = 5 x AUC) i.v. over 1 h on day 1; and etoposide 100 mg/m(2) i.v. daily on days 1-3, plus filgrastim 5 microg/kg/day. Most patients with indolent lymphoma also received rituximab. The median age of patients was 52 years (range 26-69 years). Patients received a mean of 2.8 cycles of ICE. Non-haematological toxicities included grade 1/2 CNS toxicity in four patients, cardiac toxicity in two, reversible renal impairment and haematuria in one each. Haematological toxicity included grades III/IV thrombocytopenia and neutropenia with at least one cycle of ICE in 71% and 72% of patients, respectively. The median time to PBSC harvest was 14 days (range 10-20 days), while the median CD34(+) cell yield was 4.8 x 10(6)/kg (range 2.3-37.8). Five patients (7%) failed to mobilise PBSCs. The overall response rate to ICE was 89%, comprising 29% who achieved a CR and 60% who achieved a PR; for DLBCL, the overall response rate was 85% including 36% who achieved a CR and 49% who exhibited a PR. At a median follow-up of 24 months, the Kaplan-Meier estimates of the overall and event-free survival for all patients were 65% and 42%, respectively. For patients with DLBCL overall and event-free survival figures were 51% and 35%, respectively, at a median follow-up of 14 months. These data confirm the efficacy and tolerability of outpatient fractionated ICE as both a salvage and mobilisation regimen in relapsed/refractory lymphoma.

Adolescent↗

Unrelated umbilical cord blood transplantation for adults with haematological malignancies: results from a single Australian centre.

BACKGROUND: A number of haematological malignancies can be cured by allogeneic stem cell transplantation but only approximately 30% of Australians have a suitable histocompatible related donor. Matched donors can be found on international registries of unrelated volunteers for a proportion of the remaining patients. For those patients in need of an allogeneic transplant, but for whom a suitable matched related or unrelated adult donor cannot be found, the use of banked unrelated umbilical cord blood has emerged as a potential option. However, there is uncertainty about the applicability of this technique for the majority of adult patients as a result of limitations in the number of cells in banked cord blood units and the degree of mismatching for histocompatibility antigens. AIMS: The aim of this study was to define the feasibility of allogeneic stem cell transplantation using single unrelated cord blood units in a cohort of adults with poor prognosis leukaemia or lymphoma. METHODS: Nine patients with haematological malignancies (five with acute myeloid leukaemia, one with acute lymphoblastic leukaemia, one with Hodgkin lymphoma and two with non-Hodgkin lymphomas) received transplants of cryopreserved cord blood after conditioning therapy with high-dose cyclophosphamide, total body irradiation and antithymocyte globulin. Cord units contained a median 2.6 x 10(7) nucleated cells/kg recipient bodyweight and were matched for four (seven cases) or five (two cases) major histocompatibility complex class 1 and 2 antigens. Patients were given post-transplant immunosuppression with cycosporin and methylprednisolone. RESULTS: Neutrophil recovery to 0.5 x 10(9)/L was seen by median day 30 after transplant in all seven patients who survived more than 1 month post-transplant. Platelet recovery to 50 x 10(9)/L occurred by median day 81 in five evaluable patients. Acute graft versus host disease (GVHD) grades II-IV was seen in four of seven evaluable patients and limited chronic GVHD was seen in four of five. Infection was the most common complication. Four patients died before day 100 of infection (methicillin-resistant Staphylococcus aureus septicaemia, respiratory syncitial virus pneumonia), GVHD and multi-organ failure, and intracranial bleeding. Five patients survived 7-69 months post-transplant, without evidence of relapse of the underlying malignancy. CONCLUSION: Unrelated cord blood transplantation is feasible in adults with high-risk malignancy, with infection relating to immunocompromise being the major limitation.

Adult↗

Recovery of viable CD34+ cells from cryopreserved hemopoietic progenitor cell products.

The number of CD34+ cells infused into patients at the time of autologous or allogeneic transplantation is a clinically important variable, but the viability of these cells has not been extensively documented. In this study, we analyzed the recovery of viable CD34+ cells before and after cryopreservation on 79 autologous stem cell products, using a novel flow cytometry assay without red cell lysis. For 70 PBSC harvest samples, the mean viable CD34+ cell count was 5.98 x 10(6)/kg (range 0.3-23 x 10(6)/kg) before freezing and 5.4 x 10(6)/kg (range 0.2-23 x 10(6)/kg) after thawing. The median recovery was 93% (range 48-107%), with 90% recovery for NHL (range 48-100%, n=34), 83% for multiple myeloma (range 56-106%, n=11), 92.3% for acute leukemia (range 71-100% n=7) and 94.5% for nonhematological malignancies (range 50-107% n=18). Similarly, for autologous bone marrows (n=9) the median recovery of viable CD34+ cells was 90% (range 68-100%). The recovery of viable CD34+ cells for adult (n=51) and pediatric (n=28) stem cell collections was 91 and 94%, respectively. Further examination of the correlation between the kinetics of hematological recovery and the number of viable progenitor cells infused, particularly at the lower end of the accepted dose range, may be warranted.

Antigens, CD34↗

Prognostic features for response and survival in elderly patients with de novo acute myeloid leukemia treated with mitoxantrone and intermediate dose cytarabine.

Forty-three fit elderly patients with de novo acute myeloid leukemia (AML) received chemotherapy with mitoxantrone and intermediate dose cytarabine (MIDAC) in a phase II clinical trial conducted by the Australasian Leukaemia and Lymphoma Group. The main aim of the study was to evaluate the tolerability and efficacy of MIDAC in inducing durable remissions. While the chemotherapy was generally well tolerated, less than half the patients achieved complete remission (CR) after induction and many of those in CR could not receive planned consolidation cycles. The median overall survival for all patients was 6.5 months and the median disease-free survival for those achieving CR was 8.3 months. Only 2 patients survived beyond 4 years. Factors significantly associated with shorter survival were adverse cytogenetics, marrow dysplasia and increasing age. These results suggest that only selected elderly patients with AML are likely to benefit from aggressive chemotherapy and that novel therapies are required to improve the poor prognosis of this group.

Aged↗

Haemopoietic stem cell transplantation in Australia and New Zealand, 1992-2001: progress report from the Australasian Bone Marrow Transplant Recipient Registry.

BACKGROUND: Bone marrow and blood stem cell transplantation is now used as curative therapy for a range of haematological malignancies and other conditions. The Australasian Bone Marrow Transplant Recipient Registry (ABMTRR) has recorded transplant activity in Australia since 1992; transplant centres in New Zealand have corresponded with the Registry since 1998. AIM: To describe allogeneic and autologous bone marrow and blood stem cell transplantation activity and outcomes in Australia and New Zealand from 1992 to 2001. METHODS: Each haemopoietic stem cell transplant centre in Australia and New Zealand contributes information to the Registry via a single information form compiled when a transplant is performed. An annual follow-up request is then sent from the Registry to the contributing centre at the anniversary of each individual transplant. RESULTS: Haemopoietic stem cell transplants in Australia have increased in number from 478 in 1992 to 937 in 2001, whereas in New Zealand the number has grown from 91 in 1998 to 105 in 2001, mainly as a result of an increase in autologous blood stem cell transplants. The number of hospitals contributing to the ABMTRR has grown from 20 in 1992 to 37 in 2001. The most common indication for autologous transplantation in 2001 was non-Hodgkin's lymphoma, whereas for allogeneic transplants it was acute myeloid leukaemia. The 9-year actuarial disease-free survival probability for patients aged 16 and above between 1992 and 2000 was 37% for autologous, 39% for allogeneic related donor and 30% for allogeneic unrelated donor transplants. Recurrence of the underlying disease was the main cause of death post-transplant after both allogeneic (26.3% of deaths in the first year and 68.0% of deaths in the second year) and autologous transplants (59.0% and 86.2%). Treatment-related mortality was 16.9% after allogeneic transplantation and 2.1% after autologous transplantation in 2000. CONCLUSIONS: The ABMTRR provides a comprehensive source of information on the use of bone marrow transplant, and allows for continuing analysis of changes in the application of this high-cost technology and the outcome of patients undergoing these procedures. Registry data provide a means for directing future clinical research into perceived areas of priority for improvement of outcome, such as the reduction in the risk of disease recurrence post-transplant.

Acute Disease↗

Effect of progesterone receptor a predominance on breast cancer cell migration into bone marrow fibroblasts.

Women exposed to exogenous progesterone have increased breast cancer risk, but the mechanisms of progesterone involvement in breast cancer development are unknown. In human breast and endometrium, progesterone receptor (PR) isoform expression is disrupted in premalignant lesions and predominance of one isoform, usually PRA, in invasive cancers is associated with poorer prognosis. Disrupted PR isoform expression results in disrupted progestin regulation of cell morphology, including rounded morphology and decreased adherence of cells to tissue culture flasks. The purpose of this study was to test the hypothesis that predominance of PRA affects the interaction of breast cancer cells with a physiologically relevant stromal tissue, bone marrow stroma. T-47D breast cancer cells demonstrated the ability to migrate into bone marrow fibroblasts and this was inhibited by progestin treatment. The antiprogestin RU38486 abrogated the progestin effect on migration, demonstrating that it was PR-mediated. In cells expressing a predominance of PRA, after induction of a stably integrated inducible PRA construct, the ability of progestin to inhibit breast cancer cell migration was lost. A number of integrins were progestin regulated in T-47D cells, but there was no difference in the progestin effect in cells with PRA predominance, nor were the levels of focal adhesion proteins altered in these cells. This suggested that the lack of inhibition by progestin of breast cancer cell migration in cells with PRA predominance was not mediated by PRA effects on the membrane components of the adherens junctions. In summary, this study has shown that PRA predominance has a striking functional effect on breast cancer cell migration into stromal layers. PRA predominance may render breast cancer cells relatively resistant to the inhibitory effects of progestins and one consequence of this may be increased invasion of stroma. If borne out in vivo, these findings suggest that tumours with PRA predominance may be predisposed to cancer progression and this may signal a poorer prognosis in patients.

Bone Marrow Neoplasms↗

Tuberculosis in allogeneic stem cell transplant recipients: still a problem in the 21st century.

Allogeneic stem cell transplant (ASCT) recipients have severely impaired cell-mediated immunity as a result of their conditioning regimen, immunosuppressive therapy, and graft-versus-host disease (GVHD). Accordingly, they are susceptible to bacterial, viral, and fungal infections. Mycobacterial infections can also occur in these patients, although the incidence is not high, even in countries where tuberculosis (TB) is common. We describe four patients from our hospital who developed pulmonary T tuberculous infection in the post-transplant period over a 3-year period. During that time a total of 127 patients have undergone an ASCT, representing an incidence of TB of 2.3%. The pretransplant diagnosis was acute myeloid leukemia in three patients and chronic myeloid leukemia in one case. All four patients were treated with a combination of cyclosporine and corticosteroids for acute and/or chronic GVHD. Three of the four patients were born outside Australia, each from an area where TB is endemic. Two patients died within 2 weeks of the commencement of antituberculous therapy, the third is alive and well, and the fourth died of multi-organ failure and sepsis after 4 months in hospital. A higher index of suspicion of previous TB exposure and infection is required in the assessment of ASCT recipients, particularly in those born in areas where TB is common or endemic.

Adult↗

Oral versus intravenous ganciclovir for the prophylaxis of cytomegalovirus disease after allogeneic bone marrow transplantation.

BACKGROUND: Prophylactic low dose i.v. ganciclovir in patients at risk after allogeneic bone marrow transplantation (BMT) is highly effective in the prevention of cytomegalovirus (CMV) disease and infection. AIM: In this study, we sought to assess the tolerability of oral ganciclovir in patients after allogeneic BMT. METHODS: CMV seropositive patients or those with CMV seropositive donors were randomised to be treated with i.v. ganciclovir 5 mg/kg three times weekly or oral ganciclovir 3 g daily from engraftment to day 84. The period of accrual was from May 1997 to October 1998. Patients were monitored for CMV infection by weekly serology. Thirty-one patients received oral ganciclovir and 27 patients received i.v. ganciclovir, the treatment groups being balanced for clinical characteristics and prognostic factors. RESULTS: Renal dysfunction, transfusion requirements and significant nausea and vomiting were not different. There were no documented cases of CMV disease during the study period although three patients developed CMV polymerase chain reaction positivity at various times. One patient treated with i.v. ganciclovir developed non-fatal gastrointestinal CMV disease after the study period on day 108. Eight patients in the oral group failed to complete planned therapy, whereas two patients failed to complete the i.v. course. CONCLUSION: We conclude that oral ganciclovir is a reasonable, well-tolerated alternative to i.v. ganciclovir for the prophylaxis of CMV disease after allogeneic BMT.

Administration, Oral↗

Effects of inhibitors of the chemokine receptor CXCR4 on acute lymphoblastic leukemia cells in vitro.

Stromal cell-derived factor-1 (SDF-1) is a key regulator of the behavior of normal and leukemic precursor-B (pre-B) cells. It is possible that inhibiting SDF-1-driven processes in pre-B acute lymphoblastic leukemia (ALL) may have therapeutic implications. In this study, we examined the ability of SDF-1 inhibitors to modulate pre-B ALL cell responses to SDF-1, including chemotaxis, migration into bone marrow stroma, and stroma-supported survival and proliferation on human bone marrow stromal layers. The polyphemusin II-derived inhibitors, T140, TC140012, and T134, and the bicyclam AMD3100, effectively inhibited binding of the anti-CXCR4 monoclonal antibody 12G5 on the pre-B ALL cell line NALM6, with IC(50) values of 0.9, 0.9, 0.9, and 1.9 nM, respectively. Similar results were obtained with ALL samples. T140 (0.1 micro M) and AMD3100 (1 micro M) completely blocked SDF-1-induced chemotaxis and attenuated the migration of pre-B ALL cells into bone marrow stromal layers. AMD3100 and TC140012 at a concentration of 50 micro M significantly inhibited stroma-dependent proliferation of six and four of the eight cases tested, respectively, without reducing the cell viability. In addition, AMD3100 and TC140012 enhanced the cytotoxic and antiproliferative effects of the cytotoxic agents vincristine and dexamethasone. The ability of SDF-1 inhibitors to modulate these biologically important functions of leukemic cells warrants further investigation.

Antineoplastic Agents↗

Outpatient-based ifosfamide, carboplatin and etoposide (ICE) chemotherapy in transplant-eligible patients with non-Hodgkin's lymphoma and Hodgkin's disease.

We have treated 38 transplant-eligible patients with relapsed/refractory non-Hodgkin's lymphoma and Hodgkin's disease using an outpatient-based regimen of ifosfamide, carboplatin and etoposide (ICE) for both salvage and peripheral blood stem cell mobilisation. Patients included relapsed or refractory diffuse large B-cell lymphoma (n = 17), follicular lymphoma (n = II), T-cell lymphoma (n = 2), mantle cell lymphoma (n = 2) and Hodgkin's disease (n = 6). Seven patients with diffuse large B-cell lymphoma and three patients with follicular lymphoma (26%) were considered chemorefractory. Cycles of ICE therapy were administered every 21 days as an outpatient and consisted of ifosfamide 5000 mg/m2 intravenously (i.v.) fractionated into three equally divided doses over 3 days, carboplatin [mg dose = 5 x area under the curve (AUC)] i.v. on day 1 and etoposide 100 mg/m2- i.v. daily for 3 days. Subsequently. granulocyte colony-stimulating factor (G-CSF)5 microg/kg subcutaneously (s.c.) was administered daily from day +5. Of the I I follicular lymphoma patients, 10 also received rituximab with ICE therapy. Median age of patients was 52 years (range 30-65). Patients received a mean of 2.6 cycles (range 1-4) of ICE. There were no toxic deaths and no significant non-haematological toxicities secondary to ICE therapy. Grade IV thrombocytopenia and grade IV neutropenia with at least one cycle of ICE were seen in 47% and 53% of patients, respectively. Median time to peripheral blood stem cell (PBSC) harvest was 14 days (range 10-20). while the median CD34+ cell yield was 5.2 x 10(6) cells/kg(range 2.3 x 10(6)-27.2 x 10(6)). Only one of the ICE-responders failed to mobilise PBSCs. The overall response rate to ICE was 87%. comprising 14 patients (37%) who achieved a complete response (CR) and 19 (50%) who achieved a partial response (PR). A total of 30 patients have undergone autologous stem cell transplantation(SCT) while two follicular lymphoma patients have received a non-myeloablative allogeneic SCT. Follow-up is short: however, the Kaplan-Meier estimate of the proportion of patients alive and event-free at a median follow-up of 11 months is 80% and 59%, respectively. Event-free survival for patients who achieved a CR after ICE and transplantation is 88% versus 45% for those who achieved a PR. These data confirm the efficacy and tolerability of fractionated ICE chemotherapy as both a salvage and mobilisation regimen that can be readily delivered in an outpatient setting.

Adult↗

The chemokine receptor CXCR4 enhances integrin-mediated in vitro adhesion and facilitates engraftment of leukemic precursor-B cells in the bone marrow.

OBJECTIVE: It has been demonstrated that acute lymphoblastic leukemia (ALL) blasts migrate into layers of bone marrow fibroblasts (BMF) in vitro using the beta1 integrins VLA-4 and VLA-5, and that the chemokine SDF-1 and its receptor CXCR4 influences ALL migration. We investigated whether this effect was due to SDF-1-mediated induction of adhesion through beta1 integrins. METHODS: Adhesion of pre-B ALL cells or the cell line NALM6 to extracellular matrix proteins was examined using short-term in vitro binding assays. The effects of exposure of cells to SDF-1, antibodies to CXCR4, and the G protein inhibitor pertussis toxin (PTX) were assessed. The consequences of down regulation of CXCR4 on the in vivo behavior of pre-B ALL cells after injection into sublethally irradiated NOD/SCID mice was studied. RESULTS: Treatment with SDF-1 of NALM6 cells or cells from cases of precursor-B ALL resulted in a doubling of adhesion to fibronectin, laminin, and VCAM-1, but had no effect on binding to collagens I or IV. Antibodies to CXCR4 and PTX inhibited SDF-1-induced adhesion on these substrates. NALM6 cells with CXCR4 expression downregulated by SDF-1 exposure demonstrated a reduced capacity to engraft into the bone marrow of NOD/SCID mice, with only 22 +/- 11% of marrow cells being of human origin in mice receiving SDF-1-treated cells compared to 48 +/- 5% in mice receiving untreated cells (p < 0.001). The homing of SDF-1-treated cells to the bone marrow after 24 hours was also reduced by 72 +/- 16% compared to control cells. CONCLUSIONS: These data show that SDF-1 and CXCR4 are involved in regulation of beta1 integrin function, and are important for the localization of pre-B cells to the bone marrow in vivo.

Animals↗

Allogeneic haemopoietic cell transplants in Australia, 1996--a multi-centre retrospective comparison of the use of peripheral blood stem cells with bone marrow.

A retrospective comparison was carried out on adult patients receiving HLA-identical allogeneic haemopoietic stem cell transplants from siblings in Australia in 1996, comparing bone marrow with G-CSF-mobilised peripheral blood stem cells. A total of 131 transplant recipients from nine centres were included in this study, of whom 79 received bone marrow, 44 blood stem cells and eight both. All but three of the 131 patients had cyclosporin and methotrexate as graft-versus-host disease prophylaxis. The minimum follow-up time for surviving patients is 27 months. Comparisons were carried out between the BM and PBSC groups. There were no significant differences between groups in age, sex, diagnosis, donor characteristics or pretransplant conditioning. Median time to neutrophil recovery of 0.5 x 10(9)/l was 14 days for PBSC recipients, compared to 19 days for marrow recipients (P < 0.0005). median time to platelet recovery of 20 x 10(9)/l was 17 days for PBSC recipients, compared to 28 days for marrow recipients (P < 0.0005). there were no significantly increased risks of either acute or chronic GVHD in the PBSC recipients. there were no significant differences between the groups in the incidence of major transplant-related complications, disease-free survival or overall survival.

Adolescent↗

Patterns of failure with increasing intensification of induction chemotherapy for acute myeloid leukaemia.

Patterns of failure were studied in two consecutive randomized trials of intensified induction therapy carried out by the Australian Leukaemia Study Group (ALSG) between 1984 and 1991 to determine the impact of dose intensification. Patients received standard dose cytarabine and daunorubicin (7-3), 7-3 plus etoposide (7-3-7) or 7-3 plus high-dose cytarabine (HIDAC-3-7) chemotherapy. Patients with FAB M3 morphology were excluded. Time to failure (TTF) was defined as the time from randomization to induction death or removal from study for non-responders, or to relapse or death in complete response (CR) for complete responders. An estimated 86% of 470 de novo patients with acute myeloid leukaemia failed within 10 years of randomization, as a result of death in induction in 17% of the randomized patients, failure to achieve CR in a further 17%, relapse in 44% and death in CR in 8% of patients. An estimated 66% of patients failed as a result of refractory disease or relapse within that period (disease-related failures). Multifactor analysis identified age and peripheral blast count as the most significant pretreatment factors associated with overall TTF. These factors, together with cytogenetics, were significantly associated with disease-related failures. High-dose cytarabine in induction significantly decreased the disease-related failure rate as did allogeneic transplantation in first CR. The impact of high-dose cytarabine did not depend on the cytogenetic risk group.

Acute Disease↗