Cord blood transplantation for children with acute leukaemia: a Eurocord registry analysis

OBJECTIVES: Report results of unrelated cord blood transplants collected by Eurocord Registry in children with acute leukemia. RESULTS: Children with AML: 95 children were analyzed. The two year leukemia free survival was 42% in patients transplanted in first remission, 50% in second remission and 21% in children not in remission. Children with poor prognostic cytogenetic features had the same survival compared to other patients. Children with ALL: 195 patients with ALL were analyzed. The two year leukemia free survival was 36% in patients transplanted in remission and 15% in patients transplanted in relapse. Results of unrelated cord blood transplants compared to unrelated bone marrow transplants in children with acute leukemia: 416 children with acute leukemia received a HLA matched unrelated bone marrow transplant and were compared to 99 children transplanted with an unrelated HLA mismatched cord blood. The long term outcome between these groups were comparable with delayed engraftment in cord blood transplant, more relapse in T cell depleted bone marrow transplant and more GVH in the unmanipulated bone marrow transplant resulting in similar 5 years leukemia free survival. CONCLUSION: These results show that use of unrelated cord blood transplant is an option in patients lacking an HLA identical sibling donor.     

Unrelated umbilical cord blood transplant for adult acute lymphoblastic leukemia in first and second complete remission: a comparison with allografts from adult unrelated donors

Allogeneic hematopoietic cell transplantation has an established role in the treatment of adults with acute lymphoblastic leukemia whose survival when recipients of grafts from adult unrelated donors approaches that of recipients of grafts from sibling donors. Our aim was to determine the role of mismatched unrelated cord blood grafts in transplantation for 802 adults with acute lymphoblastic leukemia in first or second complete remission. Using Cox regression we compared outcomes after 116 mismatched single or double cord blood transplants, 546 peripheral blood progenitor cell transplants and 140 bone marrow transplants. The characteristics of the recipients and their diseases were similar except cord blood recipients were younger, more likely to be non-Caucasians and more likely to have a low white blood cell count at diagnosis. There were differences in donor-recipient human leukocyte antigen-match depending on the source of the graft. Most adult donor transplants were matched at the allele-level considering human leukocyte antigens-A, -B, -C and –DRB1. In contrast, most cord blood transplants were mismatched and considered antigen-level matching; 57% were mismatched at two loci and 29% at one locus whereas only 29% of adult donor transplants were mismatched at one locus and none at two loci. There were no differences in the 3-year probabilities of survival between recipients of cord blood (44%), matched adult donor (44%) and mismatched adult donor (43%) transplants. Cord blood transplants engrafted slower and were associated with less grade 2–4 acute but similar chronic graft-versus-host disease, relapse, and transplant-related mortality. The survival of cord blood graft recipients was similar to that of recipients of matched or mismatched unrelated adult donor grafts and so cord blood should be considered a valid alternative source of stem cells for adults with acute lymphoblastic leukemia in the absence of a matched unrelated adult donor.     

Blood and marrow transplantation in the People's Republic of China

Syngeneic BMT was first performed successfully in China in 1964. In 1981, allogeneic BMT was applied in an acute leukemia patient with success. Since then, the number of BMTs has been increasing gradually, especially since the 1990s. More than 2000 stem cell transplants per year have been performed in recent years in more than 50 BMT units in mainland China. A survey of 16 BMT units from 1986 to 2005 indicates that the predominant types of transplantation performed are identical sibling (36%), related mismatched/haploidentical (11.2%), unrelated (7.5%) and autologous (44.5%) and that the distribution of disease entities and prevalent diseases being transplanted are AML (31%), ALL (16.1%), CML (19.1%) and lymphoid malignancy (22.2%). The number of transplants from unrelated donor or related mismatched/haploidentical donor has increased significantly in the past 5 years. BM and G-CSF-mobilized peripheral blood are used about equally often as a source of hematopoietic stem cells, or they are used in combination. Umbilical cord blood is used least often. Leukemias for allogeneic and lymphoid malignancies for autologous BMT continue to increase, but the increase in BMT for CML has been slow since 2004. By the end of 2007, HLA data were available on more than 700,000 individuals in the Chinese Marrow Donor Program, and 800 stem cell donations have been carried out from these. Related HLA-mismatched/haploidentical BMT has achieved comparable outcomes in terms of severe acute GVHD, chronic GVHD, relapse, treatment-related mortality, disease-free survival (DFS) and overall survival (OS) with HLA-identical sibling transplantation in the author's two BMT units. Cord blood co-infusion as the third-party cells could significantly reduce the incidence and severity of acute GVHD, steroid-refractory acute GVHD and extensive chronic GVHD without an increase in leukemia relapse and could improve DFS and OS.     

Allogeneic hematopoietic transplantation using haploidentical donor vs. unrelated cord blood donor in pediatric patients: a single-center retrospective study

We retrospectively analyzed outcomes in 67 children with acute leukemia who received hematopoietic stem cell transplantation from alternative allogeneic donors: 29 received a haploidentical family donor and 38, an unrelated cord blood donor. All transplantations were performed from 1996 through 2010 in our center. Neutrophil and platelet engraftment were significantly delayed after cord blood transplantation. The median times to neutrophil and platelet recovery were 13 d (7-34) and 11 d (5-70) after haploidentical transplant and 20 d (9-125) and 56 d (12-200) after cord blood (P < 0.001). All supportive care measures included red blood cell, and platelet transfusions were significantly increased in cord blood transplantation group.Transplant-related mortality rates was lower with haplo donors (25 ± 9%) than with cord blood donors (47 ± 9%) (P < 0.05). Acute graft-versus-host disease (GVHD) more than grade II was also lower in haploidentical transplants (19 ± 7%) than in cord blood transplants (44 ± 10%) (P < 0.03). Relapse and chronic GVHD incidence were not significantly different in the two groups. Leukemia-free survival was higher after haploidentical transplants (44 ± 10%) than after cord blood transplants (33 ± 7%) (P < 0.03). Main differences were observed in patients diagnosed with acute lymphoblastic leukemia: haplo, 41 ± 13%; cord blood, 26 ± 9% (P < 0.03) and in advanced phase of disease: haplo, 37 ± 14%; cord blood, 21 ± 8% (P < 0.05). In conclusion, haploidentical transplants are a good and promising alternative option for patients with childhood leukemia who lack an human leukocyte antigen-matched donor (sibling or unrelated donor).     

Comparative single-institute analysis of cord blood transplantation from unrelated donors with bone marrow or peripheral blood stem-cell transplants from related donors in adult patients with hematologic malignancies after myeloablative conditioning regimen.

We studied the clinical outcomes of 171 adults with hematologic malignancies who received unrelated cord blood transplantation (CBT) as a primary unrelated stem-cell source (n=100), or bone marrow transplant (BMT) or peripheral blood stem-cell transplant (PBSCT) from related donors (n=71, 55 BMT and 16 PBSCT). All patients received myeloablative regimens including 12 Gy total body irradiation. We analyzed the hematologic recovery, and risks of graft-versus-host disease (GVHD), transplantation-related mortality (TRM) and relapse, and disease-free survival (DFS) using Cox proportional hazards models. Significant delays in engraftment occurred after cord blood transplantation; however, overall engraftment rates were almost the same for both grafts. The cumulative incidences of grades III to IV acute and extensive-type chronic GVHDs among CBT recipients were significantly lower than those among BMT/PBSCT recipients. Multivariate analysis demonstrated no apparent differences in TRM (9% in CBT and 13% in BMT/PBSCT recipients), relapse (17% in CBT and 26% in BMT/PBSCT recipients), and DFS (70% in CBT and 60% in BMT/PBSCT recipients) between both groups. These data suggest that unrelated cord blood could be as safe and effective a stem-cell source as related bone marrow or mobilized peripheral blood for adult patients when it is used as a primary unrelated stem-cell source.     

Comparison of transplant outcomes from matched sibling bone marrow or peripheral blood stem cell and unrelated cord blood in patients 50 years or older

Older recipient and donor age were associated with higher incidences of severe graft‐versus‐host disease (GVHD) and mortality after allogeneic hematopoietic stem cell transplantation from matched sibling donors (MSDs) and matched unrelated donors. Since a lower incidence of severe GVHD is advantageous in unrelated cord blood transplantation (CBT), a higher incidence of GVHD using older MSDs could be overcome using cord blood for older patients. We retrospectively analyzed Japanese registration data of 2,091 patients with acute myeloid leukemia, acute lymphoblastic leukemia (ALL), and myelodysplastic syndrome aged 50 years or older who underwent MSD bone marrow transplantation (BMT) (n = 319), MSD peripheral blood stem cell transplantation (PBSCT) (n = 462), or unrelated CBT (n = 1,310) between 2007 and 2012. Median age of MSD was 56 (range, 38–74) years. Compared with CBT, the risk of developing extensive chronic GVHD was higher after BMT (hazard ratio [HR], 2.00; P = 0.001) or PBSCT (HR, 2.38; P < 0.001), and transplant‐related mortality was lower after BMT (HR, 0.61; P < 0.001) or PBSCT (HR, 0.63; P < 0.001). Relapse rates were not significant difference between three groups. Although overall mortality was lower after BMT (HR, 0.67; P < 0.001) or PBSCT (HR, 0.75; P = 0.002) compared with CBT, the rates of a composite endpoint of GVHD‐free, relapse‐free survival (GRFS) were not significant difference between three groups. These data showed that MSDs remain the best donor source for older patients, but CBT led to similar GRFS to BMT and PBSCT. Am. J. Hematol. 91:E284–E292, 2016. © 2016 Wiley Periodicals, Inc.     

Induction of remission of relapsed acute myeloid leukemia after unrelated donor cord blood transplantation by concomitant low-dose cytarabine and calcitriol in adults

Low-dose cytarabine and calcitriol (LDCA + VD3) combination therapy was performed in two adult patients with acute myeloid leukemia (AML) that relapsed within 1 yr after unrelated donor cord blood transplantation (URD CBT) performed in a relapse or non-remission stage. Concomitant aclarubicin was also administered in one patient. Remission because of recovery of donor cord blood hematopoiesis was obtained in both patients. The treatment was low intensive, and neither adverse effects in terms of digestive symptoms nor hypercalcemia was observed. Activity of daily life was maintained. The patients were followed as outpatients after remission, and the remission duration was approximately 6 months in both patients. Although LDCA + VD3 therapy is minimally intensive chemotherapy, it may prolong the survival time of patients with relapsed AML after URD CBT.     

Indications and results of cord blood transplant in children with leukemia

Umbilical cord blood transplant (UCBT) is now used more frequently for transplanting children with high-risk malignancies. The advantages are the rapid availability of donor cells, the possibility of using HLA-mismatched transplants and the decreased risk of acute and chronic GvHD. The Eurocord registry has collected and analyzed data on unrelated CBTs performed in European Blood and Marrow Transplant Group (EBMT) and non-EBMT centers. The literature shows that after UCBT relapse rate (RR), disease-free survival and overall survival of children with acute leukemia are similar to other hematopoietic stem cell sources (matched unrelated BM). Disease status at the time of transplantation is found in several studies to be a very important determinant of long-term outcome. In conclusion, UCB is a valuable alternative source of hematopoietic stem cell transplantation in children with acute leukemia who need an allogeneic transplant, but lack a suitable sibling donor.     

Pre-engraftment bloodstream infections in acute leukemia patients undergoing unrelated cord blood transplantation following intensified myeloablative conditioning without ATG

The aim of this study is to investigate the impact of pre-engraftment bloodstream infections (BSIs) on the outcomes in acute leukemia patients undergoing myeloablative cord blood transplantation (CBT). A total of 226 acute leukemia patients who received unrelated CBT were enrolled in this study, and all these patients received an intensified myeloablative conditioning without ATG. Pre-engraftment BSIs occurred in 72 patients (31.9 %), and the median time of onset was 4.5 days after cord blood infusion, BSIs of gram-negative bacilli, and gram-positive cocci comprised of 63.8 and 36.2 %, respectively. The cumulative incidences of neutrophil and platelet engraftment, acute or chronic graft versus host disease (GVHD) were comparable among the non-BSI, gram-negative bacilli BSI, and gram-positive cocci BSI groups. The cumulative incidence of transplant-related mortality (TRM), relapse, overall survival (OS), and disease-free survival (DFS) was similar between the non-BSI and the BSI groups. For subgroups analysis, TRM was lower in gram-positive cocci BSI patients compared with that of gram-negative bacilli BSI patients (8.3 vs 39.3 %) (p?=?0.01) (HR?=?0.39, p?=?0.034), and the 5-year OS was higher in gram-positive cocci BSI cohort (79.1 vs 44.2 %) (p?=?0.01) (HR?=?0.36, p?=?0.046). Our study demonstrated that, for acute leukemia patients who received CBT after myeloablative conditioning that omitted ATG, pre-engraftment BSI had no impact on engraftment, GVHD, TRM, relapse, and long-term survival. Due to the fact that gram-negative bacilli BSI was associated with poor outcomes compared with gram-positive cocci BSI, appropriate early empirical antimicrobial management strategies and better supportive care are required to decrease the gram-negative bacilli BSI-related mortality.     

Cord blood stem cell transplantation for haemoglobinopathies

Despite improvements in supportive care, patients with beta-thalassaemia major or sickle cell disease (SCD) may benefit from haematopoietic stem cell transplantation at some point during their lives. Human leucocyte antigen (HLA)-matched sibling bone marrow donors are not always available and alternative sources of stem cells have been sought, including related and unrelated donor cord blood transplants (CBT). The outcome of CBT from related donors for the treatment of both thalassaemia major and SCD is now approaching that for bone marrow transplantation, with around 90% of patients surviving disease-free. The main complication is graft rejection, which may be reduced by increasing pretransplant immune suppression. Transplant-related mortality following HLA-identical matched related donor CBT is extremely low but is significant in the small series of unrelated and/or mis-matched donor CBT. The principal limitation to extending the use of CB stem cells for the cure of haemoglobinopathies is the need to better understand the mechanisms of action and optimal conditioning regimens used to secure long-term engraftment while minimizing morbidity and mortality. Further biological studies and clinical trials are needed to address this aim.     

Factors associated with outcome after cord blood transplantation in children with acute leukemia. Eurocord-Cord Blood Transplant Group.

We have analyzed factors influencing the outcome of 102 children with acute leukemia given a cord blood transplantation (CBT) and reported to the Eurocord Registry. Seventy patients with acute lymphoblastic and 32 with acute myeloid leukemia were given either a related (n = 42) or an unrelated (n = 60) CBT. Children given CBT during first or second complete remission were considered as belonging to the good-risk group (n = 66), whereas those who received a transplant in a more advanced stage of disease were assigned to the poor-risk group (n = 36). In the related group (RCBT), 12 of 42 patients received transplantation from an HLA-disparate donor, whereas in the unrelated group (UCBT) 54 of 60 received an HLA mismatched CBT. Kaplan-Meier estimates for neutrophil recovery at day 60 were 84% +/- 7% in RCBT and 79 +/- 6% in UCBT (P =.16). In multivariate analysis, the most important factor influencing neutrophil engraftment in UCBT was a nucleated cell dose infused greater than 3.7 x 10(7)/kg (P =.05, relative risk [RR] of 1.85, 95% confidence interval [CI]: 0.98-3.4). The incidence of grade II through IV acute graft-versus-host disease was 41% +/- 8% in the RCBT group and 37% +/- 6% in the UCBT group (P =.59). Kaplan-Meier estimates of 2-year event-free survival (EFS) after RCBT or UCBT were 39% +/- 8% and 30% +/- 7%, respectively (P =.19). In multivariate analysis, the most important factor influencing EFS was disease status at time of transplantation: good-risk patients had a 2-year EFS of 49% +/- 7% as compared to 8% +/- 5% in patients with more advanced disease (P =.0003, RR: 0.40, 95% CI: 0.24 to 0. 65). This was a consequence of both an increased 1-year transplant related mortality and a higher 2-year relapse rate in the poor-risk group (65% +/- 9% and 77% +/- 14%, respectively), as compared with good risk patients (34% +/- 6% and 31% +/- 9%, respectively). These data confirm that allogeneic CBT from either a related or an unrelated donor is a feasible procedure able to cure a significant proportion of children with acute leukemia, especially if transplanted in a favorable phase of disease.     

Single-institute comparative analysis of unrelated bone marrow transplantation and cord blood transplantation for adult patients with hematologic malignancies

Unrelated cord blood transplantation (CBT) has now become more common, but as yet there have been only a few reports on its outcome compared with bone marrow transplantation (BMT), especially for adults. We studied the clinical outcomes of 113 adult patients with hematologic malignancies who received unrelated BM transplants (n = 45) or unrelated CB transplants (n = 68). We analyzed the hematopoietic recovery, rates of graft-versus-host disease (GVHD), risks of transplantation-related mortality (TRM) and relapse, and disease-free survival (DFS) using Cox proportional hazards models. The time from donor search to transplantation was significantly shorter among CB transplant recipients (median, 2 months) than BM transplant recipients (median, 11 months; P < .01). Multivariate analysis demonstrated slow neutrophil (P < .01) and platelet (P < .01) recoveries in CBT patients compared with BMT patients. Despite rapid tapering of immunosuppressants after transplantation and infrequent use of steroids to treat severe acute GVHD, there were no GVHD-related deaths among CB transplant recipients compared with 10 deaths of 24 among BM transplant recipients. Unrelated CBT showed better TRM and DFS results compared with BMT (P = .02 and P < .01, respectively), despite the higher human leukocyte antigen mismatching rate and lower number of infused cells. These data strongly suggest that CBT could be safely and effectively used for adult patients with hematologic malignancies.     

Successful transplantation of ethnically mismatched cord blood in a boy with atypical chronic myeloid leukemia

In the present study, we describe unrelated umbilical cord blood transplantation (CBT) in a 7-year-old Taiwanese boy with atypical chronic myeloid leukemia (BCR-ABL 1 negative). Physical examination was notable for splenomegaly. Cytogenetic analyses from the bone marrow revealed a t(3;5)(p21;q31) translocation. The patient then underwent CBT from an HLA-mismatched (two loci by serotype, three loci by genotype) unrelated donor of Caucasian origin. Times to neutrophil and platelet engraftment were 21 and 62 days post-transplant, respectively. Acute graft-versus-host disease following transplantation was minimal. The patient remains in continuing hematological remission with full donor chimerism 28 months after transplantation.     

Hematopoietic stem cell transplantation in sickle cell disease

Since the first report of a young girl affected by sickle cell anemia, treated successfully by bone marrow transplantation (BMT) for acute myeloid leukemia, more than 200 patients have been transplanted worldwide for sickle cell anemia. The disease-free survival (DFS) is good (80-85% in several series), even though many children who received allografts had already significant sickle-related complications. The best results are obtained in young children who have HLA-identical sibling donors and are transplanted early in the course of the disease (DFS: 93%). Future directions in the field of stem cell transplantation of sickle cell anemia include (1) the establishment of new protocols with less toxicity, but still effective, (2) adapted conditioning regimen for adult patients, and (3) new sources of stem cells for broader application: umbilical cord blood and volunteer unrelated donors.     

Family-directed umbilical cord blood banking

Umbilical cord blood transplantation from HLA-identical siblings provides good results in children. These results support targeted efforts to bank family cord blood units that can be used for a sibling diagnosed with a disease which can be cured by allogeneic hematopoietic stem cell transplantation or for research that investigates the use of allogeneic or autologous cord blood cells. Over 500 patients transplanted with related cord blood units have been reported to the Eurocord registry with a 4-year overall survival of 91% for patients with non-malignant diseases and 56% for patients with malignant diseases. Main hematologic indications in children are leukemia, hemoglobinopathies or inherited hematologic, immunological or metabolic disorders. However, family-directed cord blood banking is not widely promoted; many cord blood units used in sibling transplantation have been obtained from private banks that do not meet the necessary criteria required to store these units. Marketing by private banks who predominantly store autologous cord blood units has created public confusion. There are very few current validated indications for autologous storage but some new indications might appear in the future. Little effort is devoted to provide unbiased information and to educate the public as to the distinction between the different types of banking, economic models and standards involved in such programs. In order to provide a better service for families in need, directed-family cord blood banking activities should be encouraged and closely monitored with common standards, and better information on current and future indications should be made available.     

Successful transplantation of HLA-matched and HLA-mismatched umbilical cord blood from unrelated donors: analysis of engraftment and acute graft-versus-host disease

To reduce the morbidity and mortality associated with unrelated donor bone marrow (BM) transplantation and potentially extend the pool of suitable donors, cryopreserved unrelated donor umbilical cord blood was considered as an alternate source of hematopoietic stem cells for transplantation. Patients with leukemia, BM failure syndrome, or inborn error of metabolism were eligible for a phase I clinical trial designed to estimate the risk of graft failure and severe acute graft-versus- host disease after transplantation of umbilical cord blood from unrelated donors. As of December 21, 1995, unrelated donor umbilical cord blood was used to reconstitute hematopoiesis in eighteen patients aged 0.1 to 21.3 years weighing 3.3 to 78.8 kg with acquired or congenital lympho-hematopoietic disorders or metabolic disease. Patients received either HLA-matched (n = 7) or HLA-1 to 3 antigen disparate (n = 11) grafts collected and evaluated by the New York Blood Center (New York, NY). The probability of engraftment after unrelated donor umbilical cord blood transplantation was 100% with no patient having late graft failure to date. The probability of grade III-IV acute graft-versus-host disease at 100 days was 11%. With a median follow-up of 6 months (range, 1.6 to 17 months); the probability of survival at 6 months is 65% in this high risk patient population. We conclude that cryopreserved umbilical cord blood from HLA-matched and mismatched unrelated donors is a sufficient source of transplantable hematopoietic stem cells with high probability of donor derived engraftment and low risk of refractory severe acute graft-versus-host disease. Limitations with regard to recipient size and degree of donor HLA disparity remain to be determined.     

Factors affecting lymphocyte subset reconstitution after either related or unrelated cord blood transplantation in children -- a Eurocord analysis

Immune recovery after cord blood transplantation (CBT) is of concern owing to the low number of lymphocytes transferred with the graft and their immaturity. Risk factors influencing lymphocyte subset reconstitution related to disease, patient, donor and transplant were studied in 63 children (< 16 years), given either related (n = 14) or unrelated (n = 49) CBT for malignant (n = 33) or non-malignant diseases (n = 30). Only children with sustained myeloid engraftment were analysed. Absolute numbers of T (CD3(+), CD4(+), CD8(+)), B and natural killer (NK) cells were reported 2--3, 6, 9, 12 and 12--24 months after CBT. Median patient age was 4.0 years (0--15) and median follow-up was 23 months (1.7--61.0). Twenty-six patients received human leucocyte antigen (HLA)-matched CBT and 37 received HLA-mismatched CBT. The median number of nucleated cells (NCs) collected/recipient weight was 6.1 x 10(7)/kg. In this selected population, the estimate 2 year survival was 85%. Lymphocyte reconstitution (defined as the median time to reach the normal value of age-matched healthy children) was 3, 6 and 8 months for NK, B and CD8(+) cells, while it was 11.7 months for both CD3(+) and CD4(+) lymphocytes. In the multivariate analysis, factors favouring T-cell recovery were: related donor (P = 0.002); higher NCs/kg (P = 0.005) and recipient cytomegalovirus (CMV)-positive serology (P = 0.04). Presence of acute graft-versus-host disease (GVHD) delayed T-cell recovery (P = 0.04). To summarize, in children with sustained myeloid engraftment the concern that lymphocyte recovery after CBT could be delayed does not appear to be substantiated by our results.     

Unrelated cord blood transplantation for thalassaemia: a single-institution experience of 35 patients

Our study was designed to prospectively determine whether or not unrelated cord blood transplantation (CBT) can produce outcomes comparable to related donor transplantation for children with β-thalassaemia. In 35 patients, 40 transplants were performed between October 2003 and September 2009. HLA matching at enrolment was 6/6 (n=8), 5/6 (n=16), 4/6 (n=27), or 3/6 (n=1) by low-resolution HLA-A, -B, and high-resolution DRB1. These patients received non-manipulated grafts without ex vivo expansion or T-cell depletion. The median number of nucleated and CD34+ cells infused was 7.8 × 10(7)/kg (range, 2.8-14.7 × 10(7)/kg) and 4.0 × 10(5)/kg (range, 1.7-19.9 × 10(5)/kg), respectively. The 5-year OS and thalassaemia-free survival after the first transplant were 88.3 and 73.9%, respectively. The cumulative incidence of TRM at 2 years was 11.7%. Fourteen patients developed chronic skin GVHD. Thirty patients were alive and transfusion-independent with a Lansky performance score ≥80% achieved between 6 and 76 months post transplant (median, 36 months). These data compare acceptably with the survival rates of related-donor BMT for thalassaemia and suggest that patients without an available HLA-compatible sibling but who have well-matched unrelated donors should also be considered for CBT.     

Single-unit umbilical cord blood transplantation from unrelated donors in patients with hematological malignancy using busulfan, thiotepa, fludarabine and ATG as myeloablative conditioning regimen

Attempts to optimize outcomes in cord blood transplantation (CBT) by using new conditioning regimens and standardization of cord blood unit selection are warranted. In all, 88 patients (18 children and 70 adults) with hematological malignancy from nine Spanish institutions underwent a single-unit CBT after an i.v. BU-based myeloablative conditioning regimen. All evaluable patients except one engrafted. The overall cumulative incidence (CI) of myeloid engraftment was 94% at a median time of 19 days. In multivariate analysis, nonadvanced disease stage was the only factor with a favorable impact on myeloid engraftment. The CI of acute GVHD grades II-IV and chronic extensive GVHD were 24% each. The CI of nonrelapse mortality at 100 days, 180 days and 5 years was 14, 23 and 44%, respectively. The 5-year CI of relapse was 18%, whereas disease-free survival (DFS) was 46%, 39% and 11% for patients transplanted in early, intermediate and advanced stages of the disease, respectively. Our study shows high rates of engraftment with fast neutrophil recovery in patients undergoing single-unit CBT using a BU-based conditioning regimen. Long-term DFS can be achieved in a substantial number of patients with high-risk hematological malignancies, particularly when transplanted in an early stage of the disease.     

Allo-SCT in children with high-risk leukemia using unmanipulated grafts from alternative donors

Allogeneic HSCT is a curative treatment for high-risk leukemia. In Europe, approximately 15% of children have an HLA-matched sibling, but in 65-70% HLA allele-matched (9-10/10) unrelated donors (UD) can be identified. Transplantation using an HLA partially mismatched donor, unrelated cord blood or haploidentical family donor with graft manipulation is then considered with preference on the basis of local experience and/or availability. Here we evaluate the outcomes of 87 consecutive patients with leukemia transplanted with unmanipulated graft from matched or partially mismatched UD or cord blood (CB) at our institution between January 2001 and December 2007. Within the median follow-up of 30 months, the acute GVHD grade II was diagnosed in 70.9% patients; grades III-IV only in 4.6%. The overall incidence of chronic GVHD was 43.3% (extensive in 34.9%). The probability of 3-year EFS was 59.5% and that of 3-year overall survival was 66.9%. TRM at day +100 was 4.5%, and overall it was 13.8%. Fourteen patients (16.1%) died as a consequence of post-transplant leukemia relapse. We conclude that the prognosis of patients transplanted for leukemia using unmanipulated grafts from HLA-matched or partially mismatched UD or CB is comparable and satisfactory. TRM and relapse rate are lower than in the earlier period.