Allogeneic transplantation from HLA-matched sibling or partially HLA-mismatched related donors for primary refractory acute leukemia

Allogeneic Stem Cell Transplantation in Refractory Acute Myeloid Leukaemia

Refractory acute myeloid leukaemia is very difficult to treat and represents an unmet clinical need. In recent years, new drugs and combinations of drugs have been tested in this category, with encouraging results. However, all treated patients relapsed and died from the disease. The only curative option is allogeneic transplantation through a graft from a healthy donor immune system. Using myeloablative conditioning regimens, the median overall survival regimens is 19%. Several so-called sequential induction chemotherapies followed by allogeneic transplantation conditioned by reduced intensity regimens have been developed, improving the overall survival to 25-57%. In the allogeneic transplantation field, continuous improvements in practices, particularly regarding graft versus host disease prevention, infection prevention, and treatment, have allowed us to observe improvements in survival rates. This is true mainly for patients in complete remission before transplantation and less so for refractory patients. However, full myeloablative regimens are toxic and carry a high risk of treatment-related mortality. In this review, we describe the results obtained with the different modalities used in more recent retrospective and prospective studies. Based on these findings, we speculate how allogeneic stem cell transplantation could be modified to maximise its therapeutic effect on refractory acute myeloid leukaemia.

Thiotepa and antithymocyte globulin-based conditioning prior to haploidentical transplantation with posttransplant cyclophosphamide in high-risk hematological malignancies

We report results of a thiotepa-based conditioning in haploidentical stem cell transplantation (haplo-SCT) with posttransplant cyclophosphamide (PT-CY) and antithymocyte globulin (ATG), for unmanipulated peripheral blood stem cell (PBSC) transplants, in 80 patients with hematological malignancies. Patients in complete remission (CR) received a thiotepa-busulfan-fludarabine (TBF) regimen, while patients with relapsed/refractory (R/R) malignancies received a sequential regimen consisting of thiotepa-etoposide-cyclophosphamide (TEC) and reduced-intensity conditioning (RIC). The median age was 52 (range, 17-72) years, 44% patients had R/R disease at transplant, and the median follow-up was 417 (range, 180-1595) days. The median days to neutrophil engraftment was 17 (range, 12-34). The cumulative incidences (CI) of acute graft-versus-host disease (GVHD) grade III to IV, severe chronic GVHD, nonrelapse mortality (NRM), and relapse were 16%, 16%, 26, and 26%, respectively. The 2-year overall survival (OS) and disease-free survival (DFS) were 53% and 47%, respectively. There were no significant differences between the patients in CR and R/R patients in terms of engraftment, GVHD, NRM, relapse, OS, or DFS. We conclude that thiotepa-based regimen with PT-CY can be modified with PBSC and ATG, still providing low toxicity, protection against GVHD, and low relapse incidence. Particularly encouraging are the results with the modification to sequential regimen in R/R patients.

[Clinical observation of 12 patients with refractory/relapsed acute myeloid leukemia treated with allogeneic hematopoietic stem cell transplantation containing cladribine regimen]

Objective: To investigate the safety and efficacy of allogeneic hematopoietic stem cell transplantation (allo-HSCT) containing cladribine sequential busulfan regimen for refractory/relapsed acute myeloid leukemia (AML) . Methods: The clinical data of 12 refractory/relapsed AML patients received allo-HSCT with cladribine sequential busulfan regimen. Results: ① Of the 12 patients, 9 were males and 3 females, with a median age of 36 (27-50) years. The donors were identical sibling (3) , matched unrelated (1) and haploidentical family member (9) respectively. Nine patients reached partial remission and other remained no remission after chemotherapy before allo-HSCT. The median previous chemotherapy courses before allo-HSCT were 6 (2-13) . ② Conditioning regimen: Smostine 250 mg·m(-2)·d(-1), d-7; Cladribine 5 mg·m(-2)·d(-1), d-6 to d-2; Cytarabine Arabinoside 2 g·m(-2)·d(-1), d-6 to d-2; Busulfan 3.2 mg·m(-2)·d(-1), d-6 to d-3; Rabbit anti-human thymocyte immunoglobulin (ATG) 1.5 mg·m(-2)·d(-1) (unrelated donor transplantation) or 2.0-2.5 mg·m(-2)·d(-1) (haplo-HSCT) , d-4 to d-1. ③ Of the 12 patients, 11 patients attained complete haploidentical engraftment, one case occurred primary graft failure. The median durations for neutrophils and platelet implantations were 15 (15-21) and 19 (17-30) days respectively. ④After conditioning, no hepatic veno-occlusive diseases were observed, hemorrhagic cystitis occurred in 2 patients, 8 patients had fever, 3 cases experienced acute GVHD grade II, localized chronic GVHD occurred in 8 patients. ⑤The median follow-up was 8 (4-12) months. Leukemia relapse occurred in 2 patients at time of 6, 12 months after allo-HSCT. The estimated 1-year OS and DFS were (71.1±1.8) % and (62.2±1.8) %, respectively. Conclusions: allo-HSCT with cladribine sequential busulfan regimen was a feasible choice with favorable outcome for refractory/relapsed AML.

Fludarabine-treosulfan compared to thiotepa-busulfan-fludarabine or FLAMSA as conditioning regimen for patients with primary refractory or relapsed acute myeloid leukemia: a study from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation (EBMT)

Background

Limited data is available to guide the choice of the conditioning regimen for patients with acute myeloid leukemia (AML) undergoing transplant with persistent disease.

Methods

We retrospectively compared outcome of fludarabine-treosulfan (FT), thiotepa-busulfan-fludarabine (TBF), and sequential fludarabine, intermediate dose Ara-C, amsacrine, total body irradiation/busulfan, cyclophosphamide (FLAMSA) conditioning in patients with refractory or relapsed AML.

Results

Complete remission rates at day 100 were 92%, 80%, and 88% for FT, TBF, and FLAMSA, respectively (p = 0.13). Non-relapse mortality, incidence of relapse, acute (a) and chronic (c) graft-versus-host disease (GVHD) rates did not differ between the three groups. Overall survival at 2 years was 37% for FT, 24% for TBF, and 34% for FLAMSA (p = 0.10). Independent prognostic factors for survival were Karnofsky performance score and patient CMV serology (p = 0.01; p = 0.02), while survival was not affected by age at transplant. The use of anti-thymocyte globulin (ATG) was associated with reduced risk of grade III–IV aGVHD (p = 0.02) and cGVHD (p = 0.006), with no influence on relapse.

Conclusions

In conclusion, FT, TBF, and FLAMSA regimens provided similar outcome in patients undergoing transplant with active AML. Survival was determined by patient characteristics as Karnofsky performance score and CMV serology, however was not affected by age at transplant. ATG appears able to reduce the incidence of acute and chronic GVHD without influencing relapse risk.

Electronic supplementary material

The online version of this article (10.1186/s13045-019-0727-4) contains supplementary material, which is available to authorized users.

Clinical outcome of FLAG-IDA chemotherapy sequential with Flu-Bu3 conditioning regimen in patients with refractory AML: a parallel study from Shanghai Institute of Hematology and Institut Paoli-Calmettes

The purpose of the study was to evaluate the feasibility of conditioning regimen with sequential chemotherapy (FLAG-IDA), followed by Fludarabine (5 days) + Busulfan (3 days) by parallel analysis of patients with refractory acute myeloid leukemia (AML) from two transplantation centers in China and France. A total of 47 refractory AML with median bone marrow blast of 35% (1–90%) and median age at 42 years (16–62) were enrolled. Thirteen patients received peripheral stem cell transplantation (HSCT) from HLA-matched sibling donor, while 18 and 16 from unrelated or haplo-identical donors, respectively. With a median follow-up of 24.3 months (1–70), 13 patients relapsed at a median time of 5.1 months (2.2–18.0) and 24 patients died due to relapse (n = 12) or non-relapsed mortality (NRM, n = 12). The estimated 3-year RR and NRM were 33.5 ± 5.7% and 25.7 ± 4.2%, respectively. The estimated 3-year overall survival (OS) and event-free survival (EFS) were 43.8 ± 7.8% and 42.3 ± 7.8%. In multivariate analysis, age (<40) and low bone marrow blast were associated with better EFS, while no difference was observed between the two centers. The patients enrolled in study were unselected, representing typical patients' population of refractory AML, and primary data demonstrated the feasibility of sequential conditioning regimen.

Similar outcome of allogeneic stem cell transplantation after myeloablative and sequential conditioning regimen in patients with refractory or relapsed acute myeloid leukemia: A study from the Société Francophone de Greffe de Moelle et de Thérapie Cellulaire

Patients with acute myeloid leukemia (AML) in relapse or refractory to induction therapy have a dismal prognosis. Allogeneic hematopoietic stem cell transplantation is the only curative option. In these patients, we aimed to compare the results of a myeloablative transplant versus a sequential approach consisting in a cytoreductive chemotherapy followed by a reduced intensity conditioning regimen and prophylactic donor lymphocytes infusions. We retrospectively analyzed 99 patients aged 18-50 years, transplanted for a refractory (52%) or a relapsed AML not in remission (48%). Fifty-eight patients received a sequential approach and 41 patients a myeloablative conditioning regimen. Only 6 patients received prophylactic donor lymphocytes infusions. With a median follow-up of 48 months, 2-year overall survival was 39%, 95% confidence interval (CI) (24-53) in the myeloablative group versus 33%, 95% CI (21-45) in the sequential groups (P = .39), and 2-year cumulative incidence of relapse (CIR) was 57% versus 50% respectively (P = .99). Nonrelapse mortality was not higher in the myeloablative group (17% versus 15%, P = .44). In multivariate analysis, overall survival, CIR and nonrelapse mortality remained similar between the two groups. However, in multivariate analysis, sequential conditioning led to fewer acute grade II-IV graft versus host disease (GVHD) (HR for sequential approach = 0.37; 95% CI: 0.21-0.65; P < .001) without a significant impact on chronic GVHD (all grades and extensive). In young patients with refractory or relapsed AML, myeloablative transplant and sequential approach offer similar outcomes except for a lower incidence of acute GvHD after a sequential transplant.

Sequential intensified conditioning followed by prophylactic DLI could reduce relapse of refractory acute leukemia after allo-HSCT

The major obstacle is leukemia relapse for refractory leukemia undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT). We previously introduced a strategy of sequential intensified conditioning and early rapid immunosupressant withdrawal for refractory leukemia undergoing allo-HSCT, with 5-year overall survival (OS) and 3-year relapse rate of 44.6% and 33.3%. To reduce leukemia relapse, prophylactic donor lymphocyte infusion (DLI) was administered based on our historical strategy. A total of 153 refractory advanced acute leukemia patients were enrolled in this prospective study. According to the availability of donor lymphocytes and the criteria for DLI, 144 patients surviving day +60 were divided into two groups (80 DLI versus 64 non-DLI). The relapse rate was less and OS was better in patients receiving DLI than in those not receiving DLI (22.7% vs 33.9%, P=0.048; 58.1% vs 54.9%, P=0.043). The non-relapse mortality (NRM) was similar between DLI and non-DLI groups (P=0.104). Overall, the 5-year overall and disease-free survival post-transplantation were 51.1%±5.7% and 49.2%±5.3%. The 5-year relapse rate and NRM were 27.3%±4.4% and 29.7%±5.3%. Multivariate analysis revealed that lower bone marrow blasts on day 0, DLI and chronic graft-versus-host disease were associated with less relapse and better OS. The strategy of sequential intensified conditioning followed by early immunosupressant withdrawal and DLI could reduce relapse of refractory acute leukemia after allo-HSCT and improve survival.

Sequential Conditioning with Thiotepa in T Cell- Replete Hematopoietic Stem Cell Transplantation for the Treatment of Refractory Hematologic Malignancies: Comparison with Matched Related, Haplo-Mismatched, and Unrelated Donors

The results of conventional allogeneic stem cell transplantation (SCT) in refractory hematologic malignancies are poor. Sequential strategies have shown promising results in refractory acute myelogenous leukemia (AML), but have not been validated in a haploidentical (Haplo) transplant setting. We have developed a new sequential approach combining chemotherapy with broad antitumor activity (thiotepa 10 mg/kg, etoposide 400 mg/m², and cyclophosphamide 1600 mg/m² from day -15 to day -10), followed after 3 days of rest by a reduced-intensity conditioning regimen (fludarabine 150 mg/m², i.v. busulfan 6.4 mg/kg, and thymoglobulin 5 mg/kg from day -6 to day -2). High-dose post-transplantation cyclophosphamide was added in cases with Haplo donors. Seventy-two patients (median age, 54 years) with a refractory hematologic malignancy (44 with acute myelogenous leukemia, 7 with acute lymphoblastic leukemia, 15 with myelodysplastic syndrome/myeloproliferative neoplasms, and 6 with lymphomas) were included in this retrospective multicenter study. Donors were Haplo (n = 27), matched related (MRD; n = 16), and unrelated (UD; n = 29). With a median follow-up of 21 months, the 2-year overall survival (OS) and event-free survival (EFS) were 54.7% and 49.3%, respectively, in recipients of Haplo transplants, 49.2% and 43.8%, respectively, in recipients of MRD transplants, and 37.9% and 28%, respectively, in recipients of UD transplants. Compared with UD, the outcomes were improved in Haplo in terms of the incidences of acute grade II-IV graft-versus-host disease (GVHD) (11.1% versus 41.4%; P < .001) and GVHD-free, relapse-free survival (44.4 versus 10.3%; P = .022). These results support the safety and efficacy of a thiotepa-based sequential approach in allogeneic SCT with a Haplo donor with post-transplantation immune modulation. Thus, in patients with refractory hematologic malignancies, there seems to be no benefit in searching for a UD when a Haplo donor is readily available.

Sequential regimen of clofarabine, cytosine arabinoside and reduced-intensity conditioned transplantation for primary refractory acute myeloid leukemia

The prognosis of patients with acute myeloid leukemia in whom primary treatment fails remains very poor. In order to improve such patients' outcome, we conducted a phase 2, prospective, multicenter trial to test the feasibility of a new sequential regimen, combining a short course of intensive chemotherapy and a reduced intensity-conditioning regimen, before allogeneic stem-cell transplantation. Twenty-four patients (median age, 47 years) with acute myeloid leukemia in primary treatment failure were included. Cytogenetic risk was poor in 15 patients (62%) and intermediate in nine (38%). The sequential regimen consisted of clofarabine (30 mg/m²/day) and cytosine arabinoside (1 g/m²/day) for 5 days, followed, after a 3-day rest, by reduced-intensity conditioning and allogeneic stem-cell transplantation combining cyclophosphamide (60 mg/kg), intravenous busulfan (3.2 mg/kg/day) for 2 days and anti-thymocyte globulin (2.5 mg/kg/day) for 2 days. Patients in complete remission at day +120 received prophylactic donor lymphocyte infusion. Eighteen patients (75%) achieved complete remission. With a median follow-up of 24.6 months, the Kaplan-Meier estimate of overall survival was 54% (95% CI: 33-71) at 1 year and 38% (95% CI: 18-46) at 2 years. The Kaplan-Meier estimate of leukemia-free survival was 46% (95% CI: 26-64) at 1 year and 29% (95% CI: 13-48) at 2 years. The cumulative incidence of non-relapse mortality was 8% (95% CI: 1-24) at 1 year and 12% (95% CI: 3-19) at 2 years. Results from this phase 2 prospective multicenter trial endorsed the safety and efficacy of a clofarabine-based sequential reduced-toxicity conditioning regimen, which warrants further investigation. This study was registered at www.clinicaltrials.gov, identifier number: NCT01188174.

Prevention of relapse using granulocyte CSF-primed PBPCs following HLA-mismatched/haploidentical, T-cell-replete hematopoietic SCT in patients with advanced-stage acute leukemia: a retrospective risk-factor analysis

The role of donor lymphocyte infusion (DLI) in the prophylaxis of relapse has not been defined. We retrospectively analyzed the data from 88 patients with advanced-stage acute leukemia after HLA-mismatched/haploidentical hematopoietic SCT (HSCT) whose treatment did (n=61) or did not (n=27) include granulocyte CSF (GCSF)-primed PBPCs infusion (GPBPCI). The two groups were compared with respect to relapse and OS. Further, a detailed analysis of risk factors was performed. The 2-year cumulative incidence of relapse in patients receiving prophylactic GPBPCI and not receiving prophylactic GPBPCI were 36% and 55% (P=0.017), respectively. Estimated survival at 3 years was 31% for patients receiving prophylactic GPBPCI and 11% for patients not receiving prophylactic GPBPCI (P=0.001). The three-year probability of leukemia-free survival was also higher in patients who received prophylactic GPBPCI (22%) compared with patients who did not (11%) (P=0.003). Multivariate analysis for relapse showed that use of prophylactic GPBPCI after transplantation was an independent prognostic factor (P=0.025). Higher OS was associated with use of prophylactic GPBPCI (P=0.002), AML (P=0.027) and female sex (P=0.023). Our results suggest that use of prophylactic GPBPCI may increase survival of patients with advanced-stage acute leukemia who receive HLA-mismatched/haploidentical HSCT.

Allogeneic hematopoietic cell transplantation for acute leukemia in first relapse or second remission

Background

The role of pre-transplant salvage chemotherapy has been controversial in relapsed acute leukemia.

Methods

We investigated post-transplant outcomes in 65 patients with acute leukemia treated with allogeneic hematopoietic cell transplantation (HCT) during first relapse or second remission.

Results

The 5-year cumulative incidence of relapse (CIR) was 52.3%. Multivariate analysis for CIR revealed that patients with unfavorable cytogenetics and those not in remission at the time of HCT had a significantly high CIR (P = 0.031 and P = 0.031, respectively). Allogeneic HCT was performed in 14 patients after first relapse without salvage chemotherapy ("untreated relapse" group), 15 patients failed chemotherapy for reinduction of remission before HCT ("refractory relapse" group), and 36 patients attained second remission with salvage chemotherapy before HCT ("second remission" group). The 5-year CIR for patients in the untreated relapse group (57.1%) was higher than that for those in the second remission group (42.3%), but it was lower than that for patients in the refractory relapse group (66.7%). Among patients who underwent allogeneic HCT in relapse, those with bone marrow (BM) blasts ≤30% had a lower 5-year CIR than those in florid relapse (BM blasts >30%) (57.7% vs. 70.6%).

Conclusion

Our results do not support the role of salvage chemotherapy aimed at re-induction of remission before allogeneic HCT in patients with acute leukemia after first relapse. Patients with early relapse do not appear to benefit from salvage chemotherapy before HCT.

Diagnosis and management of acute myeloid leukemia in adults: recommendations from an international expert panel, on behalf of the European LeukemiaNet

In 2003, an international working group last reported on recommendations for diagnosis, response assessment, and treatment outcomes in acute myeloid leukemia (AML). Since that time, considerable progress has been made in elucidating the molecular pathogenesis of the disease that has resulted in the identification of new diagnostic and prognostic markers. Furthermore, therapies are now being developed that target disease-associated molecular defects. Recent developments prompted an international expert panel to provide updated evidence- and expert opinion–based recommendations for the diagnosis and management of AML, that contain both minimal requirements for general practice as well as standards for clinical trials. A new standardized reporting system for correlation of cytogenetic and molecular genetic data with clinical data is proposed.

Modified donor lymphocyte infusion after HLA-mismatched/haploidentical T cell-replete hematopoietic stem cell transplantation for prophylaxis of relapse of leukemia in patients with advanced leukemia

We evaluated the safety and efficacy of donor lymphocyte infusion (DLI) with granulocyte colony-stimulating factor priming and short-term immunosuppressive agents for prophylaxis of relapse in patients with advanced leukemia after human leukocyte antigen (HLA)-mismatched T cell-replete hematopoietic stem cell transplantation (HCT). Twenty-nine patients received prophylactic DLI at a median 75 (33-120) days after HCT. Acute graft-vs-host disease (GVHD) grades 3-4 occurred in six patients, and all cases were controlled. Eleven patients were alive and relapse-free with a probability of leukemia-free survival (LFS) of 37.3 +/- 9.6% at 3 years. Chronic GVHD was associated with a lower relapse rate and higher probability of LFS. Prophylactic-modified DLI is feasible in patients with advanced leukemia to prevent relapse after HLA-mismatched HCT.

Modified donor lymphocyte infusion (DLI) for the prophylaxis of leukemia relapse after hematopoietic stem cell transplantation in patients with advanced leukemia--feasibility and safety study

PURPOSE

We retrospectively evaluated the feasibility and safety of a modified prophylactic donor lymphocytes infusion (DLI) approach in advanced leukemia.

MATERIALS AND METHODS

Thirty-three patients with advanced leukemia received modified prophylactic DLI; that is, granulocyte colony-stimulating factor-primed peripheral blood progenitor cells instead of steady-donor lymphocyte harvests were used, and a short-term immunosuppressive agent (cyclosporine A or methotrexate 10 mg once per week for 2 to 4 weeks) was used for prevention of DLI-associated graft versus host disease (GVHD) after human leukocyte antigen-identical sibling hematopoietic stem cell transplantation.

RESULTS

Thirty-nine infusions were performed in 33 patients. The mononuclear cells and median CD3+ cells infused for DLI were 1-2 x 10(8) and 0.93 x 10(6) per kilogram, respectively. Six patients experienced II-IV-grade acute GVHD. Twenty patients developed chronic GVHD. No GVHD-related death or transfusion-related pancytopenia was observed. With an 18-month median follow-up, 16 patients were in disease-free survival, and overall survival at 1 and 1.5 years was 69.0% and 50.2%, respectively.

CONCLUSION

The modified prophylactic DLI strategy might represent a step forward in the treatment of advanced leukemia.

Perspective on the role of haploidentical transplantation in the management of hematologic malignancies: why do it?

Haploidentical hematopoietic stem cell transplantation (HSCT) using mismatched family member donors has historically been complicated by high rates of nonrelapse toxicity and the need for laboratory expertise in depleting grafts of T lymphocytes. Over the past decade, improvements in supportive care, the increased use of peripheral-blood stem cell grafts, and improved T-cell depletion techniques have reduced the incidence of graft failure and lowered the rate of nonrelapse mortality. In addition, clinical studies have demonstrated that the donor-recipient mismatch may be beneficial in this setting, stimulating an immunologic cell-mediated antileukemia effect that results in lower disease recurrence rates. All of these advances have led to improvements in outcomes following haploidentical HSCT, making it an attractive option available to some patients. Because most patients do not have a matched related donor available and time to identify an unrelated donor may be excessive, haploidentical HSCT is a potentially curative option for these patients.

Early stem cell transplantation for refractory acute leukemia after salvage therapy with high-dose etoposide and cyclophosphamide

Primary refractory acute leukemia (AL) has a poor prognosis, although some patients can be salvaged with allogeneic stem cell transplantation (SCT). Induction of complete remission (CR) with conventional chemotherapy before SCT may improve outcome in this patient population. Between March 1991 and October 2003, 59 adults with primary refractory AL were treated with continuous-infusion etoposide (VP) 2.4 to 3.0 g/m(2) followed by cyclophosphamide (Cy) 6.0-7.2 g/m(2) intravenously over 3 to 4 days with the intention of proceeding to SCT in CR1. Forty-two patients had acute myelogenous leukemia (AML), 13 patients had acute lymphoblastic leukemia (ALL), and 4 patients had acute biphenotypic leukemia. The most frequent nonhematologic toxicities were oral mucosal, gastrointestinal, and hepatic toxicities (44%, 20%, and 15% of patients, respectively). Thirty-two (57%) of 56 evaluable patients entered CR1 with a median time to platelet and neutrophil recovery of 22 and 26 days, respectively. CR1 rates were similar in AML (54%) and ALL/acute biphenotypic leukemia (67%; P = .52), and analysis of baseline characteristics did not reveal any predictors of response to VP/Cy. Twenty-nine of 32 CR1 patients subsequently underwent SCT (24 allogeneic and 5 autologous). Estimated 5-year event-free survival (EFS) and overall survival for the entire cohort are 23% and 26%, respectively. In the allogeneic SCT group, 5-year EFS was 52% for AML patients and 14% for ALL patients (P = .04), and only male sex was predictive of a favorable outcome (P = .03). VP/Cy is able to induce CR1 in most patients with primary refractory AL with an acceptable toxicity profile. Subsequent allogeneic SCT can lead to long-term EFS in a significant proportion of patients.

Sequential Regimen of Chemotherapy, Reduced-Intensity Conditioning for Allogeneic Stem-Cell Transplantation, and Prophylactic Donor Lymphocyte Transfusion in High-Risk Acute Myeloid Leukemia and Myelodysplastic Syndrome

Purpose

To improve the effect of allogeneic stem-cell transplantation by sequential use of intensive chemotherapy, reduced-intensity conditioning (RIC), and prophylactic donor lymphocyte transfusions (pDLTs) in high-risk acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS).

Patients and Methods

In a prospective study of 75 consecutive patients (median age, 52.3 years), high risk was defined by progressive or refractory disease (n = 59), second remission after early relapse (n = 8), or first remission with poor prognosis based on cytogenetics or delayed response to induction therapy (n = 8). Unfavorable karyotypes were found in 49% of informative patients, and 68 patients had medical contraindications against standard conditioning. Fludarabine (30 mg/m2), cytarabine (2 g/m2), and amsacrine (100 mg/m2) for 4 days were used for cytoreduction. After 3 days of rest, RIC consisted of 4 Gy total-body irradiation, antithymocyte globulin, and 80 to 120 mg/kg cyclophosphamide. Thirty-one patients had an HLA-identical sibling donor; 44 patients had an unrelated and/or HLA-mismatched donor. pDLT was given from day +120 in patients who were not receiving immunosuppression and were free of graft-versus-host disease (GvHD).

Results

Complete remission was induced in 66 patients (88%). With a median follow-up of 35.1 months (range, 13.6 to 47.6 months), 2-year overall and leukemia-free survival were 42% and 40%, respectively. Outcome of patients with refractory disease or with complex cytogenetic aberrations was identical to that of better prognostic subgroups. Survival was best in patients who received high CD34+ cell numbers, and in patients with limited GvHD.

Conclusion

Sequential use of intensive chemotherapy, RIC transplantation, and pDLT represents a promising approach to the treatment of high-risk AML and MDS, particularly in patients with most unfavorable prognoses.

Successful treatment of bcr/abl-positive acute mixed lineage leukemia by unmanipulated bone marrow transplantation from an HLA-haploidentical (3-antigen-mismatched) cousin

We describe a patient with bcr/abl-positive acute mixed lineage leukemia who successfully underwent transplantation in primary induction failure, using unmanipulated bone marrow from a human leukocyte antigen (HLA)-haploidentical cousin. The tumor burden was successfully reduced by the administration of imatinib mesylate (STI571) before transplantation. As graft-versus-host disease (GVHD) prophylaxis, a combination of tacrolimus and a short course of methotrexate, methylprednisolone, and mycophenolate mofetil was used. Hematopoietic reconstitution was rapid, and acute GVHD was limited to the skin (grade I). The patient is still in complete remission past day +400. This successful case suggests that HLA-haploidentical transplantation using unmanipulated marrow from a distantly related relative can be considered for patients in urgent situations who do not have HLA-identical donors.

Haploidentical vs autologous hematopoietic stem cell transplantation in patients with acute leukemia beyond first remission

This is a retrospective comparison of partially mismatched related donor transplantation (PMRDT) and autotransplantation (ABMT) in advanced acute leukemia. Patients underwent T-cell-depleted PMRDT (n=164) or ABMT (n=131) for acute myeloid leukemia (n=130) or acute lymphoblastic leukemia (n=165). Fewer PMRDT patients were in remission (29 vs 85%; P<0.0001). The 5-year cumulative incidence of transplant-related mortality (TRM) was 52% after PMRDT and 16% after ABMT (P<0.0001). The 5-year cumulative incidence of relapse was 32% after PMRDT and 54% after ABMT (P=0.006). The actuarial unadjusted 5-year disease-free survival (DFS) was 16% after PMRDT and 30% after ABMT. In Cox's regression analysis, PMRDT (P<0.0001) and age >15 years (P=0.002) were associated with higher TRM, active disease (P=0.0021), ABMT (P=0.0074) and male sex (P=0.011) with higher relapse, and age >15 years (P=0.0007) and PMRDT (P=0.047) with lower DFS. Amongst second remission patients, TRM was higher after PMRDT (P=0.0003), relapse was higher after ABMT (P=0.034), and 5-year DFS was comparable (32% ABMT and 25% PMRDT). ABMT, if feasible, may be preferable to PMRDT in advanced acute leukemia patients since lower relapse after PMRDT is offset by higher TRM. If an autograft is not feasible because of nonavailability of autologous cells or very advanced disease, PMRDT is a potential alternative.