Bone-marrow transplantation for severe aplastic anaemia using histocompatible unrelated volunteer donors

Allogeneic bone marrow transplantation for aplastic anemia

After more than 60 years of intense research in allogeneic hematopoietic cell transplantation (HCT), this therapy has progressed from one that was fraught with seemingly insurmountable complications to a standard treatment of patients with aplastic anemia. During the 1970s and 1980s, HCT donors were almost exclusively HLA-identical siblings. Subsequent advances in the understanding of the complexity of the HLA region along with the development of molecular HLA typing and the establishment of unrelated volunteer donor registries have resulted in an ever-increasing use of such donors. Most recent breakthroughs have enabled HLA-haploidentical HCT and, thereby, finding donors for nearly every patient. The outstanding outcomes reported with any of the donor options have made allogeneic HCT the preferred treatment over immunosuppressive therapy.

Three decades of transplantation for chronic myeloid leukemia: what have we learned?

Last year marked 30 years of hematopoietic stem cell transplantation as a curative treatment of chronic myeloid leukemia (CML). Initially studies used stem cells from identical twins but techniques rapidly developed to use cells first from HLA-identical siblings and later unrelated donors. During the 1990s CML became the most frequent indication for allogeneic transplantation worldwide. This, together with the relative biologic homogeneity of CML in chronic phase, its responsiveness to graft-versus-leukemia effect and the ability to monitor low level residual disease placed CML at the forefront of research into different strategies of stem cell transplantation. The introduction of BCR-ABL1 tyrosine kinase inhibitors during the last decade resulted in long-term disease control in the majority of patients with CML. In those who fail to respond and/or develop intolerance to these agents, transplantation remains an effective therapeutic solution. The combination of tyrosine kinase inhibitors with transplantation is an exciting new strategy and it provides inspiration for similar approaches in other malignancies.

Unrelated donor marrow transplantation for congenital immunodeficiency and metabolic disease: an update of the experience of the Japan Marrow Donor Program

We retrospectively analyzed the clinical results of 81 patients with congenital genetic diseases who were treated with bone marrow transplantation (BMT) from unrelated donors identified through the Japan Marrow Donor Program. The patients were aged between 1 and 38 years (median, 4 years). Thirty-five patients underwent transplantation for metabolic disease (MD), ie, mucopolysaccharidosis (n = 25), adrenoleukodystrophy (n = 7), and others (n = 3). The remaining 46 patients had Wiskott-Aldrich syndrome (n = 16), hemophagocytic syndrome including the inherited type (n = 9), severe combined immunodeficiency (n = 6), hyper-IgM syndrome (n = 4), Chédiak-Higashi syndrome (n = 3), Kostmann syndrome (n = 3), and others (n = 5). Fifty-two donor-patient pairs were fully matched at HLA-A, HLA-B, and HLA-DRB1 alleles. The remaining 24 patients received allele-mismatched grafts (20 matched at 5 of 6 loci and 4 matched at 4 of 6 loci). Engraftment occurred in 82.4% of the MD group and 90.7% of the other genetic disease (OGD) group; however, 14 patients (18.2%) experienced either early or late graft failure. The cumulative incidence of grade II to IV acute graft-versus-host disease (GVHD) was 35.5% - 9.8% in the MD group and 47.3% - 9.5% in the OGD group, and the rate of chronic GVHD was 20% in both groups. Forty-nine patients have survived for 3 to 96 months (median, 20 months). The probabilities of 5-year overall survival and event-free survival were 72.6% - 11.5% and 65.3% - 8.6%, respectively, for MD (n = 35) and 72.5% - 7.3% and 63.6% - 7.3% for OGD (n = 46). Although patient status before BMT and the occurrence of grade III to IV acute GVHD significantly affected outcome, unrelated BMT is a curative therapeutic option for children with congenital genetic diseases who have no HLA-matched family donors.

Hematopoietic stem cell transplantation for severe aplastic anemia--experience of an institute in Taiwan

Hematopoietic stem cell transplantation (HSCT) is an accepted treatment strategy for patients with severe aplastic anemia (SAA). We report our experience in a general hospital in Taiwan. From March 1985 to July 2001, 79 consecutive SAA patients, 46 male and 33 female, with a median age of 22 (4-43) years, received 80 courses of transplantation. Cyclophosphamide and total body radiation were used for the conditioning regimen, and cyclosporine-A and methotrexate for graft-versus-host disease (GVHD) prevention. Patients were followed for a median of 39 months (from 8 days to 194 months). Myeloid and platelet engraftment occurred in a median of 15 (8-27) days and 18 (8-77) days, respectively. Three patients had primary and three patients secondary graft failure. Five patients (6.8%) had grade II-IV acute GVHD in 73 evaluable patients. Chronic GVHD occurred in 23 (34.8%) patients, with extensive stage in six. Only two patients had CMV disease. The projected 3- and 5-year overall survival rates estimated by the Kaplan-Meier method were 76.08 and 74.13%, respectively. Age at transplant, non-sibling donor, mononuclear cell dose, grade II-IV acute GVHD, interval from diagnosis to transplant, and red blood cell and platelet transfusion before transplant were poor prognostic factors for overall survival by univariate analysis. Grade II-IV acute GVHD was the only prognostic factor affecting overall survival after multivariate Cox regression analysis (P=0.040). In conclusion, SAA patients receiving HSCT have good long-term survival. The low incidence of acute GVHD in our patients may be related to ethnicity.

Stem cell transplantation for aplastic anemia

Survival of patients with aplastic anemia treated with transplantation of bone marrow has improved significantly over the past several decades. Allogeneic bone marrow transplantation (BMT) for patients with HLA-identical siblings is now the first-line therapy, and long-term survival of approximately 90% can be expected with cyclophosphamide/antithymocyte globulin conditioning and postgrafting methotrexate/cyclosporine immunosuppression. The outcome of unrelated donor BMT has also improved significantly with the identification of a preparative regimen with less toxicity combined with the development of high-resolution DNA-based HLA typing to identify the optimal unrelated marrow donor. Patients with fully HLA-matched unrelated donors should be considered candidates for transplantation prior to exposure to repeat courses of immunosuppression. Future progress in hematopoietic stem cell transplantation for aplastic anemia will be directed toward further decreasing the acute toxicity and decreasing the delayed effects of the conditioning regimens while maintaining highly reliable rates of sustained engraftment with prevention of acute and chronic graft-versus-host disease.

Genomics of unrelated-donor hematopoietic cell transplantation

Unrelated-donor hematopoietic cell transplantation is a proven curative modality for hematologic malignancies. The success of unrelated-donor transplantation has been achieved through a better understanding of the immunobiology of the HLA system and through more precise and comprehensive matching of donors and recipients. The extensive polymorphism of HLA genes confers important biological implications affecting engraftment, graft-versus-host disease and overall survival. Although more-complete HLA identity of the donor and recipient is associated with optimal transplant outcome, new information suggests that not every HLA disparity is functionally relevant. Future advances in unrelated-donor transplantation must include the identification of tolerable HLA mismatches, so that more patients may benefit from this therapeutic modality. Furthermore, the role of cytokine-gene polymorphisms and minor histocompatibility genes in transplant outcome requires investigation. Delineation of the function of these markers as transplantation determinants may provide alternative means for optimizing the results of hematopoietic cell transplantation.

Unrelated allogeneic bone marrow donation: short- and long-term follow-up of 103 consecutive volunteer donors

Between 1992 and 1999, 105 unrelated allogeneic bone marrow collections from 103 volunteer donors (65 males and 38 females; median age 33 years) were carried out in three northern Italian centers (Verona, Bolzano and Padova) affiliated with the Italian Bone Marrow Donor Registry (IBMDR). The average volume of BM collected was equivalent in both genders (1143.1 ml for males and 1054.2 ml for females; P = 0.1), although the average volume collected for unit of body weight and the average post-collection blood volume depletion was higher in females (respectively 17.1 ml/kg and 14.2% in females, 14.8 ml/kg and 12% in males; P= 0.01 and 0.03). There was no statistically significant difference between males and females in the total number of nucleated cells collected. We did not record any acute life-threatening event during or after the bone marrow collections. The most frequent complaint was pain at the collection site (77%) followed by the onset of fatigue (38%) and nausea and vomiting (25%); all of these were short-term problems. Hospitalization was short (average 20.2 h) and donors started their normal daily activities after an average of 5.4 days. We also monitored Hb, serum ferritin levels, WBC and platelet counts in the post-collection period (average follow-up 40.1 months). All donors signed a written informed consent for a further bone marrow collection, if needed. Our findings confirm the short- and long-term safety of allogeneic bone marrow collection in volunteer donors.

Current status of allogeneic bone marrow transplantation in acquired aplastic anemia

Bone marrow transplantation is an effective therapy for aplastic anemia. Infusion of allogeneic hematopoietic stem cells after high-dose immune suppression restores normal hematopoiesis in most patients and long-term follow-up has confirmed the durability of donor hematopoiesis. However, success of this approach is limited by transplant-related complications, such as graft failure, graft-versus-host disease, and various organ toxicities. Long-term survival rates range from less than 40% to more than 90% in reported series. These rates have improved over the past 20 years due to significant reductions in graft-versus-host disease, interstitial pneumonitis, and early transplant-related mortality. Most long-term survivors have excellent performance status. Late effects such as cataracts, thyroid disorders, joint problems, and therapy-related cancers are observed, especially in patients who received radiation for pretransplant conditioning. Results are best in young patients transplanted with bone marrow from a human leukocyte antigen (HLA)-identical sibling; early transplantation is appropriate in this group. For older patients or those without an HLA-identical related donor, transplants are better reserved for those who fail to respond to immunosuppressive therapy.

Allogeneic transplantation from donors other than HLA-identical siblings

The decade of the 1990s has witnessed impressive advances in the use of alternative donors for allogeneic transplantations. Through funded collaborative, and single-center research efforts, there is great promise that complete and equal access to allogeneic transplantation will be realized. In the next decade, universal donor availability should maximize the patient's chance of overcoming otherwise fatal disease.

Unrelated donor transplant therapy for chronic myelogenous leukemia

Unrelated donor transplant therapy for chronic myelogenous leukemia is both feasible and effective. As discussed in this article, clinical outcome can be predicted based on several patient characteristics and transplant conditions. Highly selected subsets of patients experience outcomes not appreciably different from recipients of related donor transplants. In many cases, however, unrelated donor transplant is associated with significant peritransplant mortality and other complications. The impact of recent improvements in donor-recipient typing, marrow procurement, graft-versus-host disease prevention and treatment, medical support, and donor selection should soon become apparent.

Clinical aspects of aplastic anemia

Severe aplastic anemia is a disorder characterized by peripheral pancytopenia and marrow hypoplasia. Although its pathophysiology is understood poorly, the majority of patients appear to have some immunologic destruction or suppression of hematopoietic cells. The only curative therapy to date is allogeneic stem cell transplantation, although the success of palliative immunosuppressive therapies has improved over the last two decades. Making the best therapy choice is complex and often requires balancing very divergent toxicity profiles, both acute and long-term.

Immunology of hematopoietic stem cell transplantation: a brief review of its history

The history of clinical marrow transplantation since 1968 is reviewed with an emphasis on immunological and immunogenetic aspects. The events leading to the creation of an international network of volunteer donor registries and the implementation of unrelated allogeneic marrow transplantation as a routine procedure are discussed. Current major issues which need to be resolved are addressed in order to set the stage for the topics covered in this volume of Immunological Reviews.

Unrelated donor bone marrow transplantation for hematological malignancies-current status

We have explored the efficacy and toxicity of hematopoietic stem cell transplantation from unrelated donors for hematologic malignancies and other disorders. While most marrow donors have been identified through the National Marrow Donor Program in cooperation with many international registries, the recent development of unrelated donor umbilical cord blood (UCB) banks has allowed us to also evaluate this stem cell source. Analysis of the first 211 URD BMT performed at the University of Minnesota shows an overall survival of 33%, with older recipient age and transplant from a donor with a major HLA-A or B mismatch independently associated with poorer survival. Analysis of engraftment of URD marrow shows increasing risk of delayed or incomplete engraftment with increasing HLA disparity between URD and recipient. GVHD is increased in recipients of URD marrow compared with recipients of related donor marrow. Malignant relapse, however, is less frequent in URD marrow recipients, perhaps due to an increased graft-versus-leukemia effect. Formal assessment shows quality of life in long term URD BMT survivors (beyond 2 years) is excellent, and not different from that seen in sibling marrow recipients. Data from patients receiving unrelated donor UCB transplantation at the University of Minnesota indicate that UCB is an acceptable alternate source of stem cells, at least for young recipients, and may be associated with a reduced incidence of GVHD. Ongoing studies at the University of Minnesota include examination of the applicability of unrelated UCB transplantation to adult recipients, and of the degree of HLA-incompatibility which can be tolerated in UCB transplantation. Studies to identify the optimal GVHD prophylaxis for URD BMT, and to examine the role of class II matching in transplant outcome are in progress.

Analysis of 462 transplantations from unrelated donors facilitated by the National Marrow Donor Program

BACKGROUND AND METHODS

Allogeneic bone marrow transplantation is curative in a substantial number of patients with hematologic cancers, marrow-failure disorders, immunodeficiency syndromes, and certain metabolic diseases. Unfortunately, only 25 to 30 percent of potential recipients have HLA-identical siblings who can act as donors. In 1986 the National Marrow Donor Program was created in the United States to facilitate the finding and procurement of suitable marrow from unrelated donors for patients lacking related donors.

RESULTS

During the first four years of the program, 462 patients with acquired and congenital lymphohematopoietic disorders or metabolic diseases received marrow transplants from unrelated donors. The probability of engraftment by 100 days after transplantation was 94 percent, although 8 percent of patients later had secondary graft failure. The probability of grade II, III, or IV acute graft-versus-host disease was 64 percent, and the probability of chronic graft-versus-host disease at one year was 55 percent. The rate of disease-free survival at two years among patients with leukemia and good prognostic factors was 40 percent and among patients at higher risk, 19 percent. Twenty-nine percent of the patients with aplastic anemia were alive at two years, and the rate of two-year disease-free survival among patients with myelodysplasia was 18 percent. For patients with congenital immunologic or nonimmunologic disorders, the probability of survival was 52 percent.

CONCLUSIONS

The National Marrow Donor Program has benefited a substantial number of patients in need of marrow transplants from closely HLA-matched unrelated donors and has facilitated the recruitment of unrelated donors into the donor pool and the access to suitable marrow.

Treatment of CML with unrelated donor marrow transplant

Chronic myelogenous leukemia (CML) is a uniformly lethal malignant disorder of the hematopoietic stem cell. Although CML cannot be cured with conventional therapy, recent results suggest that therapy with marrow transplantation may prolong survival and, in some cases, provide curative therapy. Approximately 30% of otherwise eligible marrow transplant candidates have an HLA matched or one antigen mismatched related donor. Related donor marrow transplantation therapy for patients in the chronic phase of CML results in 45-70% long-term, disease-free survival. Younger recipient age, transplant in chronic rather than advanced phase and transplant within one year of diagnosis provide a better outcome. Graft versus host disease (GVHD), pneumonia and systemic infections are commonly encountered complications. T-lymphocyte depletion of donor marrow reduces the incidences of acute and chronic graft versus host disease but is associated with a higher relapse rate and lower overall incidence of disease-free survival than use of non-T-depleted marrow. The use of HLA matched or one antigen mismatched unrelated donors allow successful marrow transplantation in approximately 30% of CML cases where a suitably matched related donor is not available. Unrelated donor marrow transplantation can provide stable engraftment in the majority of recipients and lead to leukemia-free survival in many cases. The beneficial effects of unrelated donor marrow transplantation are particularly apparent in young, chronic phase recipients and when performed using donor/recipient pairs identical at the HLA A, B and DR loci. A higher incidence of graft failure and GVHD than observed in sibling marrow transplant as well as prolonged convalescence in some cases can be anticipated.(ABSTRACT TRUNCATED AT 250 WORDS)

Unrelated donor marrow transplantation for severe aplastic anaemia

Severe aplastic anaemia (SAA) is frequently a lethal disease. Allogeneic marrow transplantation may offer the best chance of a cure but more than 50% of eligible patients will lack a suitable family donor. The development of large volunteer registries has established unrelated donor marrow transplantation (UD-BMT) as a possible alternative in these patients. Early clinical studies indicate that UD-BMT for SAA is associated with a significantly greater risk of graft rejection and graft-versus-host disease (GVHD) than identical sibling BMT. Current strategies for improving results of UD-BMT for SAA include improved patient selection, more precise HLA matching between recipient and unrelated donor, and the use of more intensive pre-BMT immunosuppression and GVHD prophylaxis.

Successful allogeneic transplantation of T-cell-depleted bone marrow from closely HLA-matched unrelated donors

We describe a four-year experience with bone marrow transplantation involving closely HLA-matched unrelated donors and 55 consecutive patients with hematologic disease who were seven months to 48.6 years old (median, 18 years). An intensive pretransplantation conditioning regimen and graft-versus-host disease (GVHD) prophylaxis with CD3-directed T-cell depletion and cyclosporine were employed. Durable engraftment was achieved in 50 of 53 patients who could be evaluated (94 percent; 95 percent confidence interval, 83 to 98 percent). Acute GVHD of Grade II to IV developed in 46 percent of the patients (confidence interval, 27 to 66 percent). The incidence and severity of acute GVHD were increased in recipients of HLA-mismatched marrow as compared with recipients of phenotypically matched marrow (incidence of 53 percent [confidence interval, 37 to 68 percent] vs. 17 percent [confidence interval, 5 to 45 percent]; P less than 0.05). Extensive chronic GVHD and deaths not due to relapse also tended to be more frequent when HLA-mismatched marrow was used, but not significantly so. With a median follow-up of more than 19 months (range, greater than 9 to greater than 39), the actuarial disease-free survival of transplant recipients with leukemia and a relatively good prognosis (acute leukemia in first remission and chronic myelogenous leukemia in chronic phase) was 48 percent (confidence interval, 24 to 73 percent), and that of recipients with more aggressive leukemia was 32 percent (confidence interval, 18 to 51 percent); the actuarial survival of recipients with non-neoplastic disease was 63 percent (confidence interval, 31 to 86 percent). We conclude that marrow transplantation with closely HLA-matched unrelated donors can be effective treatment for neoplastic and non-neoplastic diseases. Although transplants from phenotypically HLA-matched unrelated donors appear to be most effective, transplants with limited HLA disparity can also be successful in some patients.

Transfusion and bone marrow transplantation

Bone marrow transplantation has prolonged the lives of a significant percentage of patients with a variety of both malignant and nonmalignant disorders. However, the impact of this treatment on a transfusion service is substantial. Large numbers of often specialized blood products are required to support these patients, and the logistics of accomplishing this taxes the ingenuity and resources of even large regional blood programs.

HLA-matched donor registries for bone marrow transplants. A decision analysis

Bone marrow transplantation has become an accepted treatment for severe aplastic anemia, acute myelogenous leukemia, and acute lymphocytic leukemia (20;35). Less commonly thalassemia (23), multiple myeloma (25), severe combined immune deficiencies (10), and chronic granulocytic leukemia (14) are also treated with marrow transplantation. Most donors are siblings whose HLA phenotype is identical to the patient's. Such donors, however, are available to only one third of patients (6;16;27;28;35). In the absence of an HLA-identical sibling, partially matched, haplo-identical, related donors (differing by only one major histocom-patibility antigen) can be found for another 7% of patients (1;6;27;37). A variety of lower quality matches also can be found but have not been used extensively. Advances in tissue typing and the treatment of graft versus host disease now allow physicians to consider matchedunrelatedindividuals as potential donors when a suitable related donor is not available (11;12;13;15;17;22).

Comparison between bone marrow transplantation and antithymocyte globulin in treatment of young patients with severe aplastic anemia

Fifty-seven patients younger than 25 years with severe aplastic anemia underwent either bone marrow transplantation or antithymocyte globulin therapy (ATG) to ascertain which approach should be used in young patients. Thirty-five patients who had an HLA-identical sibling donor underwent bone marrow transplantation after conditioning with cyclophosphamide and low-dose total-body radiation. Twenty-two patients who did not have an HLA-identical donor received ATG. The 2-year actuarial survival of patients after transplant is 72% (95%, CI 64% to 80%), versus 45% (95%, CI 29% to 61%) in those given ATG therapy (P = 0.18). In those patients surviving 6 months after treatment, return of peripheral blood counts to normal values was more common in patients who received marrow transplant compared with those given ATG therapy (P less than 0.001). Furthermore, 24 of 26 transplant survivors had Karnofsky performance scores greater than 90%, compared with only five of 13 ATG survivors. These data suggest that bone marrow transplantation is the preferred therapy for severe aplastic anemia in young patients who have an HLA-identical sibling donor. ATG should be reversed for those young patients with severe aplastic anemia who do not have a histocompatible marrow donor.

The anaesthetic management of bone marrow harvest for transplantation

The anaesthetic management of 217 donors undergoing 236 operative procedures to donate bone marrow for allogeneic transplantation or for autologous grafting is described. The procedures were those performed between November 1979 and the end of October 1982.

Bone marrow transplantation for diseases of childhood

Bone marrow transplantation in childhood is an established treatment modality for aplastic anemia, the acute and chronic leukemias, and severe combined immune deficiency. Recently, experience with this treatment has also been favorable with small numbers of children who have Wiskott-Aldrich syndrome, several types of inherited storage diseases, Fanconi's anemia, thalassemia, infantile malignant osteopetrosis, and selected cases of lymphoma and other solid tumors. The psychosocial impact and financial costs of bone marrow transplantation can be substantial. Multi-institutional, prospective, randomized trials that would compare transplantation and conventional therapy are necessary to establish the indications and precise timing for this procedure. Further development of monoclonal antibodies, a better understanding of the histocompatibility antigen systems, and improvement in pretransplantation conditioning regimens should increase the spectrum of effectiveness for bone marrow transplantation in the coming years.

Mismatched family donors for bone-marrow transplantation as treatment for acute leukaemia

35 patients were treated for acute myeloid leukaemia or acute lymphoblastic leukaemia with allogeneic bone-marrow grafts from a parent, child, or sibling who was mismatched at the major histocompatibility complex (MHC). 11 of these patients are alive at least 6 months after grafting, 5 of them after more than 2 years. Of the 15 patients aged under 20 at the time of the graft, 8 are alive and well 6 months to 3 years later. Cyclosporin A was given to all patients after grafting. 1 patient died of acute graft-versus-host disease and in 2 other cases this was a major factor in their death. Graft failure caused the death of 2 patients. 4 patients died of recurrent leukaemia. A fatal complication in 12 patients was pulmonary oedema, often associated with convulsions, intravascular haemolysis, and renal failure. Some of these patients had viral or bacterial infections, but in the majority the syndrome was not associated with demonstrable infection. This syndrome, in which the essential lesion appears to be vascular, was much more common in recipients of mismatched than matched grafts. 3 others died from lung disease in which infection was a factor.