Prospective Multicenter Study of Single-Unit Cord Blood Transplantation with Myeloablative Conditioning for Adult Patients with High-Risk Hematologic Malignancies

Although the use of cord blood transplantation (CBT) is increasing, the optimal methods for conditioning and graft-versus-host disease (GVHD) prophylaxis remain to be established. Among previous reports, the Institute of Medical Science, University of Tokyo (IMSUT) has reported remarkably favorable results of CBT for hematologic malignancies as a single-institute experience. The aim of the present multicenter prospective study was to assess the safety and efficacy of CBT performed precisely according to IMSUT transplantation procedures. Thirty-three adult patients with hematologic malignancies, such as acute leukemia, chronic myelogenous leukemia, or myelodysplastic syndrome, either lacking an HLA-identical sibling/HLA-matched unrelated donor or requiring urgent transplantation were enrolled. Conditioning consisted of total body irradiation (12 Gy), cytarabine, and cyclophosphamide. Cyclosporine A and methotrexate were used for GVHD prophylaxis. Diagnoses were acute leukemia in 26 patients, chronic myelogenous leukemia in 4, and myelodysplastic syndrome in 3; 12 patients were in first complete remission, and the others were in advanced stages at the time of CBT. Thirty-one patients achieved engraftment, and the cumulative incidence of grade II-IV acute GVHD was 45% (95% confidence interval, 28%-62%). With a median follow-up of 46.2 months in 16 surviving patients, the 1-year cumulative incidence of nonrelapse mortality was 15% (95% confidence interval, 5%-30%). Causes of nonrelapse mortality were infection (n = 4) and graft failure (n = 1). The overall and disease-free survival rates were 51% (95% CI, 34%-68%) and 42% (95% CI, 26%-59%), respectively. These results suggest that the IMSUT CBT procedures can safely provide a high disease-free survival rate in patients with high-risk hematologic malignancies.     

Double Umbilical Cord Blood Transplantation after Novel Myeloablative Conditioning Using a Regimen of Fludarabine,Busulfan, and Total Lymphoid Irradiation

We conducted a pilot study evaluating double umbilical cord blood transplantation (dCBT) after myeloablative conditioning with fludarabine and busulfan 3.2 mg/kg i.v. × 4, followed by total lymphoid irradiation at 400 cGy (FluBu4/TLI) for any indicated hematological disorder for patients without a suitable donor. Twenty patients with predominantly high-risk disease underwent dCBT according to protocol. The regimen was well tolerated, with mucositis as the primary observed toxicity (n = 19). The cumulative incidence of neutrophil engraftment was 89% (95% confidence interval [CI], 64% to 97%), with a median time to recovery of 16 days (range, 12 to 31 days). All evaluable patients with neutrophil engraftment achieved complete donor chimerism by day 40. The cumulative incidence of grades III and IV acute graft-versus-host disease (GVHD) at day 100 was 10% (95% CI, 2% to 27%), and the cumulative incidence of chronic GVHD was 35% (95% CI, 16% to 55%) by the end of the study. At 1 year, the cumulative incidence of treatment-related mortality (TRM) was 35% (95% CI, 16% to 55%). The leading cause of nonrelapse mortality was acute GVHD (n = 4), followed by graft failure (n = 2) and chronic GVHD (n = 1). TRM was significantly associated with a pretransplantation hematopoietic cell transplantation–specific comorbidity index score ≥ 3 (P = .005). At 1 year, disease relapse occurred in 6 patients and overall survival was 40% (95% CI, 19% to 60%). We conclude that FluBu4/TLI is an adequate preparative regiment before dCBT, providing high engraftment rates and relatively early neutrophil recovery. The best survival outcomes were seen in patients without significant comorbidities before transplantation, and outcomes are comparable to previously published dCBT studies.     

Promising Progression-Free Survival for Patients Low and Intermediate Grade Lymphoid Malignancies after Nonmyeloablative Umbilical Cord Blood Transplantation

Nonmyeloablative hematopoietic cell transplantation (HCT) has been used to treat patients with advanced or high-risk lymphoid malignancies. We studied 65 patients (median age 46 years) receiving an umbilical cord blood (UCB) graft after a single conditioning regimen consisting of cyclophosphamide (50 mg/kg) on day −6, fludarabine (40 mg/m²) daily on days −6 to −2, as well as a single fraction of total-body irradiation (TBI) (200 cGy) along with cyclosporine mycophenolate mofetil immunosuppression. Median time to neutrophil and platelet recovery was 7.5 days (range: 0-32) and 46 days (range: 8-111), respectively. Cumulative incidences of grade II-IV, grade III-IV acute, and chronic graft-versus-host disease (aGVHD, cGVHD) were 57% (95% confidence interval [CI]: 43%-70%), 25% (95% CI: 14%-35%), and 19% (95% CI: 9%-29%), respectively. Transplant-related mortality at 3 years was 15% (95% CI: 5%-26%). Median follow-up was 23 months. The progression free-survival (PFS), current PFS and overall survival (OS) were 34% (95% CI: 21%-47%), 49% (95% CI: 36%-62%), and 55% (95% CI: 42%-70%) at 3 years. Based on our data, we conclude that a nonmyeloablative conditioning regimen followed by UCB transplantation is an effective treatment for patients with advanced lymphoid malignancies who lack a suitable sibling donor.     

Unrelated Cord Blood Transplantation for Severe Aplastic Anemia

In the present study we evaluated the feasibility of unrelated cord blood transplantation (UCBT) in patients with severe aplastic anemia (SAA). The outcome of 31 SAA patients (median age 28; range: 0.9-72.3 years old) who received UCBT was analyzed. The cumulative incidences of the neutrophil and platelet recovery after UCBT were 54.8 and 72.2%, respectively (95% confidence interval [CI] = 36.0%-70.3% and 51.3%-85.3%, respectively). The cumulative incidences of grade ≥II acute and chronic graft-versus-host disease (aGVHD, cGVHD) were 17.1% (95% CI = 6.2%-32.8%) and 19.7% (95% CI = 6.2%-38.8%), respectively. Currently, 13 patients are alive, having survived for 33.7 months (median; range: 6-77 months) after UCBT. The probability of overall survival (OS) at 2 years was 41.1% (95% CI = 23.8%-57.7%). A conditioning regimen that included low-dose total body irradiation (TBI) (2-5 Gy), fludarabine, and cyclophosphamide resulted in a favorable OS (80%; 95% CI = 20.4%-96.9%). This result suggests that UCBT using the optimal conditioning regimen can be a salvage treatment for patients without a suitable bone marrow donor and warrants evaluation in further prospective studies.     

Successful allogeneic stem cell transplantation with nonmyeloablative conditioning in patients with relapsed hematologic malignancy following autologous stem cell transplantation.

The use of myeloablative preparative therapy and allogeneic stem cell transplantation (alloSCT) as salvage therapy for adult patients with relapsed hematologic malignancy after autologous stem cell transplantation (autoSCT) is generally unsuccessful due to very high treatment-related mortality rates. We evaluated the outcome of HLA-matched related donor alloSCT following nonmyeloablative preparative therapy in 13 patients (median age, 38 years) with relapsed hematologic malignancies (Hodgkin's disease, n = 4; Hodgkin's disease and advanced myelodysplastic syndrome, n = 1; non-Hodgkin's lymphoma, n = 6; multiple myeloma, n = 2) after initial autoSCT. Median time from autoSCT to alloSCT was 12 months (range, 3-24 months); 6 patients had chemotherapy-refractory disease following autoSCT, 6 were in untreated relapse, and 1 had a partial response from salvage chemotherapy. Preparative therapy consisted of cyclophosphamide, 150-200 mg/kg; peritransplantation anti-thymocyte globulin; thymic irradiation (in patients who had not received previous mediastinal irradiation); and a very short course of cyclosporine as GVHD prophylaxis. All patients achieved initial mixed chimerism as defined by greater than 1% donor peripheral white blood cells. Seven patients, who had no evidence of GVHD, received prophylactic DLI beginning 5 to 6 weeks after transplantation for conversion of mixed chimerism to full donor hematopoiesis and to optimize a graft-versus-tumor effect. Six patients showed conversion to full donor chimerism and 1 lost the graft. Grade II or greater acute GVHD occurred in 9 patients. Seven patients achieved a complete response; 6 had no response. The median survival time of the 13 patients is currently 10 months (range, 3-39 months), with an overall survival probability at 2 years of 45% (95% confidence interval [CI], 19%-73%) and a disease-free survival probability at 2 years of 37.5% (95% CI, 12%-65%). Thus, this novel nonmyeloablative alloSCT strategy followed by prophylactic DLI was well tolerated and can result in durable disease-free survival among patients with advanced hematologic malignancies after a failed autoSCT. Further follow-up and evaluation of additional patients are required to conclusively establish the role of this strategy in the treatment of hematologic malignancies after an autologous transplantation.     

Diffuse alveolar hemorrhage and infection-associated alveolar hemorrhage following hematopoietic stem cell transplantation: related and high-risk clinical syndromes.

Diffuse alveolar hemorrhage (DAH) is a noninfectious pulmonary complication of hematopoietic stem cell transplantation (HSCT) with unclear pathogenesis and treatment. We reviewed prospectively collected data on 1919 consecutive transplants performed between 1995 and 2004 and compared patients with DAH and infection-associated alveolar hemorrhage (IAH) who presented with similar symptoms of hypoxemia, pulmonary infiltrates, and progressively bloody alveolar lavage but also had microorganisms isolated from blood, bronchoalveolar lavage, or tracheal aspirate within 1 week of alveolar hemorrhage. Overall, 116 patients had alveolar hemorrhage (45 with DAH, 71 with IAH). Older age, allogeneic donor source, myeloablative conditioning regimen, and acute severe graft-versus-host disease (GVHD) were independently predictive of an increased risk of post-HSCT alveolar hemorrhage. The DAH and IAH groups were comparable except for a higher proportion of patients receiving umbilical cord blood as a donor source and total-body irradiation-containing conditioning in the IAH group. The probability of 60-day survival from onset of hemorrhage was 16% (95% CI, 6%-26%) for the DAH and 32% (95% CI, 21%-43%) for the IAH group (P = .08). All except 20 patients were treated with a standard regimen of high-dose corticosteroids. Patients who received corticosteroids had 60-day survival of 26% (95% CI, 18%-34%), compared with 25% (95% CI, 6%-44%) for those who did not (P = .28). The pathogenesis of alveolar hemorrhage after HSCT is multifactorial, and we propose that IAH and DAH in HSCT recipients are related clinical syndromes with similar clinical presentation, risks, and associated high mortality.     

Higher Donor Apheresis Blood Volumes Are Associated with Reduced Relapse Risk and Improved Survival in Reduced-Intensity Allogeneic Transplantations with Unrelated Donors

Allogeneic hematopoietic stem cell transplantation (HSCT) with reduced-intensity conditioning (RIC) offers a curative option for patients with hematologic malignancies who are unable to undergo myeloablative conditioning, but its success is limited by high rates of relapse. Several studies have suggested a role for T cell doses in peripheral blood stem cell grafts in RIC HSCT. Because T cell dose is typically not known until after the collection, and apheresis blood volume is easily modifiable, we hypothesized that higher donor apheresis blood volumes would improve transplantation outcomes through an effect on graft composition. Thus, we analyzed the relationships between apheresis volume, graft composition, and transplantation outcomes in 142 consecutive patients undergoing unrelated donor allogeneic RIC HSCT. We found that apheresis volume ≥15 L was associated with a significantly decreased risk of relapse (adjusted hazard ratio [aHR], .48; 95% confidence interval [CI], .28 to .84]; P?=?.01) and improved relapse-free survival (aHR, .56; 95% CI, .35 to .89; P?=?.02) and overall survival (aHR, .55; 95% CI, .34 to .91; P?=?.02). A high apheresis volume was not associated with increased rates of acute or chronic graft-versus-host disease. These results demonstrate that an apheresis volume of at least 15 L is independently predictive of improved transplantation outcomes after RIC allogeneic HSCT.     

Sustained Donor Engraftment in Recipients of Double-Unit Cord Blood Transplantation Is Possible Despite Donor-Specific Human Leukoctye Antigen Antibodies

The impact of human leukocyte antigen (HLA) donor-specific antibodies (DSA) on cord blood (CB) engraftment is controversial. We evaluated the influence of pre-existing HLA-antibodies (HLA-Abs) on engraftment in 82 double-unit CB recipients (median age, 48 years) who underwent transplantation for hematologic malignancies. Of 28 patients (34%) with HLA-Abs, 12 had DSA (median mean fluorescence intensity 5255; range, 1057 to 9453). DSA patients had acute leukemia (n = 11) or myelodysplasia (n = 1) and all received either high-dose or reduced-intensity (but myeloablative) conditioning. After myeloablative CB transplantation (CBT) (n = 67), sustained donor engraftment was observed in 95% without HLA-Abs (median, 23 days), 100% with nonspecific HLA-Abs (median, 23 days), and 92% with DSA (median, 31 days, P = .48). Of 6 patients with HLA-Abs to 1 unit, 3 engrafted with that unit and 3 with the other. Of 6 patients with HLA-Abs against both units, 1 had graft failure despite being 100% donor, and 5 engrafted with 1 unit. Successful donor engraftment is possible in patients with DSA after myeloablative double-unit CBT. Our data suggest potential deleterious effects of DSA can be abrogated in patients with hematologic malignancies.     

Superior Survival of Black Versus White Patients Following Post-Transplant Cyclophosphamide-Based Haploidentical Transplantation for Adults with Hematologic Malignancy

Available evidence from large registry studies has shown inferior survival for black adult patients following both unrelated donor and cord blood transplantation. Post-transplant cyclophosphamide (PTCy)–based haploidentical donor transplantation (HIDT) is being increasingly used in ethnic minorities. However, no studies of the impact of race on outcomes following HIDT have been reported. We analyzed 203 consecutive patients (123 white, 80 black) who underwent first HIDT using PTCy for hematologic malignancy at a single institution. Median recipient age was 53 (range, 19-75) years. Peripheral blood stem cells (PBSCs) were used as the stem cell source in 66% of patients, and conditioning intensity was myeloablative (MA) in 41%. After a median follow-up of 36 months, the estimated 3-year overall survival (OS), disease-free survival (DFS), and cumulative incidence of relapse (CIR) were significantly better in black patients, compared with white patients (72% [95% confidence interval (CI), 60% to 81%], 65% [95% CI, 52% to 75%], and 25% [95% CI, 16% to 35] versus 50% [95% CI, 40% to 59%], 45% [95% CI, 36% to 54%], and 39% [95% CI, 31% to 47%], respectively; P?<?.001 for OS and DFS, P?=?.015 for CIR). In contrast, 3-year nonrelapse mortality was similar between black (11%) and white (16%) patients, as were the incidences of acute graft-versus-host disease (GVHD) and moderate-to-severe chronic GVHD. Improved survival was noted in all subgroups of black patients—younger versus older, male versus female, lower versus higher disease risk index, MA versus non-MA conditioning, or PBSC versus marrow stem cell source. In multivariate analysis, black race was independently associated with better OS (hazard ratio [HR], .47; P?=?.003), DFS (HR, .49; P?=?.003), and relapse (HR, .49; P?=?.01). Black patients achieve superior outcomes to their white counterparts following PTCy-based HIDT due to a decreased incidence of disease relapse.     

Radiation-free allogeneic conditioning with fludarabine, carmustine, and Thiotepa for acute lymphoblastic leukemia and other hematologic malignancies necessitating enhanced central nervous system activity

Total body irradiation has been the mainstay of conditioning since the inception of allogeneic hematopoietic cell transplantation, but toxicity often precludes its use. For less-fit patients with acute lymphoblastic leukemia and other hematologic malignancies frequently affecting the central nervous system, we designed a radiation-free regimen with fludarabine (25 mg/m(2)/day on days -6 to -4), carmustine (400 mg/m(2) on day -6), and thiotepa (5 mg/kg twice daily on days -5 and -4), all of which readily penetrate the blood-brain barrier and have potent antileukemic and lymphotoxic activity. Here we present a series of 30 consecutive patients with high-risk or relapsed disease who underwent allogeneic hematopoietic cell transplantation with this protocol. The median patient age was 60 years (range, 42-70 years), and the median follow-up was 968 days (range, 58-1989 days). Graft-versus-host disease prophylaxis consisted of cyclosporine A and alemtuzumab (10-20 mg). At 2 years, overall survival was 52% (95% confidence interval [CI], 34%-71%), event-free survival was 39% (95% CI, 22%-57%), cumulative incidence of relapse/progression was 30% (95% CI, 17%-52%), and treatment-related mortality was 31% (95% CI, 18%-53%). Neurologic toxicity is a concern, especially in older and heavily pretreated patients. Our experience indicates the feasibility of this regimen as an alternative to total body irradiation and a potentially curative option for less-fit patients who need a highly central nervous system-active conditioning.     

Unrelated donor hematopoietic stem cell transplantation for patients with hematologic malignancies using a nonmyeloablative conditioning regimen of fludarabine, low-dose total body irradiation, and rabbit antithymocyte globulin.

Hematopoietic stem cell chimerism can be established after low-dose conditioning regimens, although the risk of donor cell rejection increases for unrelated donor transplantations. We added pretransplantation rabbit antithymocyte globulin (6 mg/kg) to an established conditioning regimen of fludarabine (90 mg/m2) and single-fraction total body irradiation (200 cGy) followed by postgrafting immunosuppression with cyclosporine A and mycophenolate mofetil for 22 patients with hematologic malignancies. One patient rejected the graft and successfully underwent transplantation with cells from a second donor by using the same conditioning regimen. The actuarial probability of developing acute graft-versus-host disease grade II to IV before day 100 was 40%, although 9 of 14 patients who survived beyond 100 days developed chronic graft-versus-host disease. These data support a hypothesis that the addition of antithymocyte globulin decreases the risk of graft-versus-host and host-versus-graft reactions when combined with a nonmyeloablative conditioning regimen of fludarabine and total body irradiation.     

Transplantation-Related Mortality,Graft Failure,and Survival after Reduced-Toxicity Conditioning and Allogeneic Hematopoietic Stem Cell Transplantation in 100 Consecutive Pediatric Recipients

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) with myeloablative conditioning is associated with a 10%-40% risk of day +100 transplantation-related mortality (TRM). We evaluated the feasibility and safety of reduced-toxicity conditioning and allo-HSCT in 100 consecutive children and adolescent recipients (mean age, 9.2 ± 6.8 years). The mean duration of follow-up was 1278 ± 1042 days. Fifty patients had malignant disease. The median time to neutrophil recovery was 18 days, and the median time to platelet recovery was 43 days. Median donor chimerism in engrafted patients was 98% on day +100 and 98% on day +365. The cumulative incidence of acute graft-versus-host disease (GVHD) was 20% (95% confidence interval [CI], 12.1%-27.9%), and that of chronic GVHD was 13.5% (95% CI, 6.6%-20.4%). TRM was 3% (95% CI, 0%-6.4%) by day +100 and 13.6% (95% CI, 6.7%-20.5%) for the entire study period. The incidence of primary graft failure (PGF) was 16% overall, 31.4% after umbilical cord blood transplantation (UCBT), and 0% after allo-HSCT with matched unrelated or matched sibling donors (P < .0001). The incidence of PGF in UCBT recipients was 46.7% (14 of 30) in chemotherapy-naive recipients, versus 9.5% (2 of 21) in non–chemotherapy-naive recipients (P = .019). Five-year event-free survival was 59.5% ± 5%, and 5-year overall survival was 72.9% ± 5%. Only PGF and poor-risk disease status were significantly associated with decreased overall survival (P = .03). Reduced-toxicity conditioning allo-HSCT in pediatric recipients is associated with low TRM; however, chemotherapy-naive UCBT recipients have a significantly higher incidence of PGF.     

Development of Grade II Acute Graft-versus-Host Disease Is Associated with Improved Survival after Myeloablative HLA-Matched Bone Marrow Transplantation using Single-Agent Post-Transplant Cyclophosphamide

Post-transplant cyclophosphamide (PTCy) can be used as the sole immunosuppression after myeloablative conditioning (MAC) for HLA-matched bone marrow transplantation (BMT). However, the effects of graft-versus-host disease (GVHD) with this platform are undefined. We retrospectively analyzed 298 consecutive adult patients with hematologic malignancies who engrafted after MAC HLA-matched sibling donor (MSD; n = 187) or HLA-matched unrelated donor (MUD; n = 111) T-cell–replete BMT with PTCy 50 mg/kg on days +3 and +4. After MSD and MUD BMT, 35% and 57% of patients, respectively, developed grade II acute GVHD (aGVHD) by 100 days, 11% and 14% grade III to IV aGVHD by 100 days, and 9% and 16% chronic GVHD (cGVHD) by 1 year. In landmark analyses at 100 days after HLA-matched BMT, 4-year overall survival (OS) and progression-free survival (PFS) were 57% (95% confidence interval [CI], .49 to .67) and 40% (95% CI, .31 to .51) in patients without grades II to IV aGVHD, and 68% (95% CI, .59 to .78) and 54% (95% CI, .44 to .65) in patients with grade II aGVHD. In adjusted time-dependent multivariable analyses, grade II aGVHD was associated with improved OS (hazard ratio, .58; 95% CI, .37 to .89; P = .01) and PFS (hazard ratio, .50; 95% CI, .34 to .74; P < .001) after HLA-matched BMT with PTCy. The ability of PTCy to limit grades III to IV aGVHD and cGVHD while maintaining grade II aGVHD may contribute to its effectiveness, and further attempts to reduce aGVHD may be detrimental.     

Late Complications and Quality of Life after Reduced-Intensity Conditioning Allogeneic Stem Cell Transplantation

Late complications (LC) and quality of life (QOL) were analyzed in 110 adult patients who underwent reduced-intensity conditioning (RIC) allogeneic stem cell transplantation (allo-SCT) and were alive for more than 2 years after allo-SCT. Overall survival of these patients was 93% (95% confidence interval [CI], 88% to 99%) and 81% (95% CI, 71% to 94%) at 5 and 10 years, respectively. The primary cause of death was a recurrence of primary malignancy. With a median follow-up of 4.6 years (range, 2 to 12.1), chronic graft-versus-host disease (cGVHD) was the most prevalent late effect, with a cumulative incidence of 66% (95% CI, 57% to 74%) at 10 years. Cardiovascular complications were the most prevalent LC with a cumulative incidence of 47% (95% CI, 35% to 59%), followed by pulmonary complications with a cumulative incidence of 33% (95% CI, 21% to 46%) and renal impairment with a cumulative incidence of 34% (95% CI, 25% to 43%) at 10 years. Secondary malignancies occurred with a cumulative incidence of 11% (95% CI, 5% to 20%) at 10 years. In this series, 61 patients (55%) responded to QOL survey. With the use of European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire–Core 30 and Functional Assessment of Cancer Therapy–Bone Marrow Transplant questionnaires, most of the patients reported good to excellent QOL and patients with cGVHD had significantly lower QOL than patients without cGVHD. In conclusion, QOL after RIC is comparable to that seen after myeloablative conditioning, while the natural history of LC after RIC appears to be different from that described in the standard myeloablative setting, warranting further research in this field.     

Favorable Outcome of Post-Transplantation Cyclophosphamide Haploidentical Peripheral Blood Stem Cell Transplantation with Targeted Busulfan-Based Myeloablative Conditioning Using Intensive Pharmacokinetic Monitoring in Pediatric Patients

Haploidentical hematopoietic stem cell transplantation (haplo-HSCT) with post-transplantation cyclophosphamide (PTCy) was performed previously in adults using a nonmyeloablative conditioning regimen and bone marrow as a graft source. In an effort to reduce relapse rates, myeloablative conditioning regimens with higher intensities are now used. We used an intensive daily pharmacokinetic monitoring method for busulfan dosing in children for effective myeloablation and to reduce toxicity. Here, we report the retrospective results of 34 patients (median age 11.1 years) who underwent haplo-HSCT with PTCy using a targeted busulfan-based myeloablative conditioning regimen and peripheral blood as a stem cell source. The donor-type neutrophil engraftment rate was 97.1%, and the cumulative incidence rates of grade II to IV and grade III to IV acute and extensive chronic graft-versus-host disease were 38.2%, 5.9%, and 9.1%, respectively. The overall survival and event-free survival rates, and treatment-related mortality were 85.0%, 79.4%, and 2.9%, respectively. Based on the subgroup analysis of patients with malignancies (n?=?23), the relapse incidence rate was 21.7%. Haplo-HSCT using PTCy with targeted busulfan-based myeloablative conditioning and peripheral blood as a stem cell source was a safe and promising therapeutic option for children.     

Effect of ABO Blood Group Incompatibility on the Outcome of Single-Unit Cord Blood Transplantation after Myeloablative Conditioning

ABO blood group incompatibility between donor and recipient has been associated with poor transplant outcomes in allogeneic hematopoietic stem cell transplantation. However, its effect on the outcome of cord blood transplantation (CBT) has yet to be clarified. We retrospectively analyzed 191 adult patients who received single-unit CBT after myeloablative conditioning for malignant disease in our institute. Major mismatch showed a significantly lower incidence of platelet engraftment compared with ABO match as a reference (hazard ratio, .57; P = .01). Nevertheless, there was no increase in graft-versus-host disease, transplant-related mortality, and overall mortality after ABO-incompatible CBT. These data suggested that donor–recipient ABO incompatibility does not have a significant impact on outcome after myeloablative CBT for hematological malignancies.     

Allogeneic stem cell transplantation for patients with advanced hematological malignancies: comparison of fludarabine-based reduced intensity conditioning versus myeloablative conditioning

We compared the outcomes of allogeneic hematopoietic stem cell transplantation using reduced intensity and myeloablative conditioning for the treatment of patients with advanced hematological malignancies. A total of 75 adult patients received transplants from human leukocyte antigen-matched donors, coupled with either reduced intensity (n=40; fludarabine/melphalan, 28; fludarabine/cyclophosphamide, 12) or myeloablative conditioning (n=35, busufan/cyclophosphamide). The patients receiving reduced intensity conditioning were elderly, or exhibited contraindications for myeloablative conditioning. Neutrophil and platelet engraftment occurred more rapidly in the reduced intensity group (median, 9 days vs. 18 days in the myeloablative group, p<0.0001; median 12 days vs. 22 days in the myeloablative group, p=0.0001, respectively). Acute graft-versus-host disease (>or=grade II) occurred at comparable frequencies in both groups, while the incidence of hepatic veno-occlusive disease was lower in the reduced intensity group (3% vs. 20% in the myeloablative group, p=0.02). The overall 1-yr survival rates of the reduced intensity and myeloablative group patients were 44% and 15%, respectively (p=0.16). The results of present study indicate that patients with advanced hematological malignancies, even the elderly and those with major organ dysfunctions, might benefit from reduced intensity transplantation.     

Reduced-Intensity Conditioning Followed by Related and Unrelated Allografts for Hematologic Malignancies: Expanded Analysis and Long-Term Follow-Up

Reduced-intensity conditioning (RIC) extends the curative potential of allogeneic hematopoietic cell transplantation (HCT) to patients with hematologic malignancies unable to withstand myeloablative conditioning. We prospectively analyzed the outcomes of 292 consecutive patients, median age 58 years (range, 19 to 75) with hematologic malignancies treated with a uniform RIC regimen of cyclophosphamide, fludarabine, and total body irradiation (200 cGy) with or without antithymocyte globulin and cyclosporine and mycophenolate mofetil graft-versus-host disease (GVHD) prophylaxis followed by allogeneic HCT at the University of Minnesota from 2002 to 6. Probability of 5-year overall survival was 78% for patients with indolent non-Hodgkin lymphoma, 53% for chronic myelogenous leukemia, 55% for Hodgkin lymphoma, 40% for acute myelogenous leukemia, 37% for myelodysplastic syndrome, 29% for myeloma, and 14% for myeloproliferative neoplasms. Corresponding outcomes for relapse were 0%, 13%, 53%, 37%, 39%, 75%, and 29%, respectively. Disease risk index (DRI) predicted both survival and relapse with superior survival (64%) and lowest relapse (16%) in those with low risk score compared with 24% survival and 57% relapse in those with high/very-high risk scores. Recipient cytomegalovirus (CMV)-positive serostatus was protective from relapse with the lowest rates in those also receiving a CMV-positive donor graft (29%). The cumulative incidence of 2-year nonrelapse mortality was 26% and was lowest in those receiving a matched sibling graft at 21%, with low (21%) or intermediate (18%) HCT-specific comorbidity index, and was similar across age groups. The incidence of grades II to IV acute GVHD was 43% and grades III to IV 27%; the highest rates were found in those receiving an unrelated donor (URD) peripheral blood stem cell (PBSC) graft, at 50%. Chronic GVHD at 1 year was 36%.Future approaches incorporating alternative GVHD prophylaxis, particularly for URD PBSC grafts, and targeted post-transplant antineoplastic therapies for those with high DRI are indicated to improve these outcomes.     

Comparison of unrelated cord blood transplantation and HLA-mismatched unrelated bone marrow transplantation for adults with leukemia

Recent advances in unrelated cord blood transplantation (UCBT) and high-resolution typing of human leukocyte antigen (HLA) from an unrelated donor have increased choices in alternative donor/stem cell source selection. We assessed HLA-mismatched locus-specific comparison of the outcomes of 351 single-unit UCB and 1,028 unrelated bone marrow (UBM) adult recipients 16 years old or older at the time of transplantation who received first stem cell transplantation with myeloablative conditioning for acute leukemia or myelodysplastic syndromes. With adjusted analyses, HLA 0 to 2 mismatched UCBT showed similar overall mortality (relative risk [RR] = 0.85, 95% confidence interval [CI], 0.68-1.06; P = .149) compared with that of single-HLA-DRB1-mismatched UBMT. UCBT showed inferior neutrophil recovery (RR = 0.50, 95% CI, 0.42-0.60; P < .001), lower risk of acute graft-versus-host disease (RR = 0.55, 95% CI, 0.42-0.72; P < .001), and lower risk of transplantation-related mortality (RR = 0.68, 95% CI, 0.50-0.92; P = .011) compared with single-HLA-DRB1-mismatched UBMT. No significant difference was observed for risk of relapse (RR = 1.28, 95% CI, 0.93-1.76; P = .125). HLA 0 to 2 antigen-mismatched UCBT is a reasonable second alternative donor/stem cell source with a survival outcome similar to that of single-HLA-DRB1-mismatched or other 7 of 8 UBMT.     

Allogeneic Stem Cell Transplantation for Adults with Myelodysplastic Syndromes: Importance of Pretransplant Disease Burden

Allogeneic stem cell transplantation is the only known curative therapy for myelodsyplastic syndromes (MDS). We present the transplant outcomes for 84 adult MDS patients, median age 50 (18-69 years), undergoing allogeneic hematopoietic stem cell transplantation (HSCT) at the University of Minnesota between 1995 and 2007. By WHO criteria 35 (42%) had refractory anemia with excess blasts (RAEB-1 or 2), 23 (27%) had refractory cytopenia with multilineage dysplasia (RCMD) or RCMD and ringed sideroblasts (RCMD-RS), and the remaining 26 (31%) had refractory anemia (RA), myelodysplastic syndrome-unclassifiable (MDS-U), chronic myelomonocytic leukemia (CMML), myelodysplastic/myeloproliferative disease (MDS/MPD), or myelodysplastic syndrome-not otherwise specified (MDS-NOS). Graft source was related in 47 (56%), unrelated donor (URD) marrow in 11 (13%), and unrelated cord blood (UCB) in 26 (31%). The conditioning regimen included total body irradiation (TBI) in 94% of transplantations; 52 (62%) myeloablative (MA) and 32 (38%) nonmyeloablative (NMA) regimens. Cumulative incidence of neutrophil engraftment by day +42, acute graft-versus-host disease (aGVHD) by day +100, and chronic GVHD (cGVHD) by 1 year were 88% (80%-96%, 95% confidence interval [CI]), 43% (36%-50%, 95% CI), and 15% (10%-20%, 95% CI), respectively. One-year treatment-related mortality (TRM), relapse, disease-free survival (DFS), and overall survival (OS) were 39% (28%-50%, 95% CI), 23% (12%-32%, 95% CI), 38% (28%-48%, 95% CI), and 48% (38%-58%, 95% CI) respectively. Cumulative incidence of relapse at 1 year in patients with pre-HCT complete remission (CR) or <5% blasts was improved at 18% (8%-28%, 95% CI) compared to 35% (16%-54%, 95% CI) in patients with 5%-20% blasts (P = .07). Additionally, with MA conditioning, the incidence of relapse at 1 year trended lower at 16% (6%-26%, 95% CI) versus 35% (18%-52%, 95% CI) in NMA (P = .06), and a statistically significant decrease in relapse was noted in patients entering HCT with CR or <5% blasts with an incidence of 9% (0%-18%, 95% CI) (MA) versus 31% (11%-51%, 95% CI) (NMA) (P = 0.04). For those patients with ≥5% blasts, MA conditioning did not significantly decrease relapse rates. One-year TRM was similar between MA and NMA conditioning. For patients entering transplant in CR or with <5% blasts, prior treatment to reach this level did not impact rates of relapse or transplant-related mortality when all patients were analyzed; however, when broken down by conditioning intensity, there was a trend toward improved DFS in those NMA patients who were pretreated. Finally, 1-year DFS was similar using related donor peripheral blood stem cell (PBSC)/marrow, URD marrow, or UCB grafts. These data suggest that (1) blast percentage <5% at HSCT is the major predictor of improved DFS and relapse and prior treatment to reach this disease status may have value in leading to improved DFS; (2) MA conditioning is associated with lower relapse risk, particularly in patients with CR or <5% blasts, but is not able to overcome increased disease burden; (3) NMA conditioning yields equivalent TRM, DFS, and OS, and is reasonable in patients unsuited for MA conditioning; (4) the donor sources tested (PBSC, bone marrow [BM], or UCB) yielded similar outcomes.