Predictive factors for outcome of allogeneic hematopoietic cell transplantation for adult acute lymphoblastic leukemia

Humanized CD19 CAR-T cells in relapsed/refractory B-ALL patients who relapsed after or failed murine CD19 CAR-T therapy

BACKGROUND

For CD19-positive relapsed/refractory B-cell acute lymphoblastic leukemia (r/r B-ALL) after treatment with murine CD19 (mCD19) CAR-T, the reinfusion of mCD19 CAR-T cells may be ineffective due to anti-mouse single-chain variable fragment (scFv) antibody caused by mCD19 CAR. To overcome this immunogenicity, we applied humanized CD19 (hCD19) CAR-T cells to treat r/r B-ALL patients with prior mCD19 CAR-T therapy.

METHODS

Nineteen pediatric and adult patients were included, 16 relapsed after and 3 were primarily resistant to mCD19 CAR-T. All patients presented with more than 5% blasts in bone marrow and/or extramedullary disease, and still showed CD19 antigen expression. Humanized CD19-CARs were lentiviral vectors carrying a second generation CAR with 4-1-BB co-stimulatory and CD3ζ signaling domains. Patient-derived cells were collected for producing CAR-T cells, the median dose of infused hCD19 CAR-T cells was 2.4 × 10⁵/kg (range, 1.0-18.0 × 10⁵/kg).

RESULTS

hCD19 CAR-T resulted in a complete remission (CR) rate of 68% (13/19). Among 13 remission patients, 11 underwent allogeneic hematopoietic cell transplantation (allo-HCT) (3 were second HCT) and 10 remained in CR; the event-free survival rates at 12-18 months were 91% in 11 patients received following allo-HCT and 69% in all CR patients. Six cases had no response to hCD19 CAR-T, 3 died of disease progression; another 3 received salvage second transplantation, of them, 2 relapsed again (one died). Cytokine release syndrome (CRS) occurred in 95% (18/19) of patients, most CRS events were grade 1 and grade 2 (n = 17), there was only one grade 4 CRS. Two cases experienced grade 1 neurotoxicity.

CONCLUSIONS

Humanized CD19 CAR-T cell therapy could be a treatment option for CD19-positive B-ALL patients who relapsed after or resisted prior murine CD19 CAR-T, hCD19 CAR-T followed by allo-HCT provided a longer remission in CR patients. Nevertheless, the prognosis of non-responders to hCD19 CAR-T remained dismal.

TRIAL REGISTRATION

Chinese Clinical Trial Registry/WHO International Clinical Trial Registry ( ChiCTR1900024456 , URL: www.chictr.org.cn ); registered on July 12, 2019.

Unintended Regulatory Caused Early Death-A Difficult Endpoint in Cancer Patient Care and Treatment

Simple Summary

This is a position paper by a clinical oncologist. It voices concerns about political decision making and regulatory time frames for drug availability, both of which are critical for patient care in life-threatening diseases such as cancer.

Abstract

The pharmacological armory against cancer has been growing, with many new drugs approved. The Good Clinical Practice (GCP)-based Clinical Trials Directive was adopted in the EU in 2001, with the important objectives of achieving better patient safety and improved quality of clinical trial conduct. However, clinical experience with the implementation of the regulation raises the question as to whether aspects of this regulatory framework can cause harm to some patients. This question also arises in daily clinical cancer patient care when the time between the publication of pivotal study results and their approval, and details of post-approval regulations, are scrutinized. Clinical observations, provocatively summarized as “unintended regulatory caused early death”, are discussed.

Haploidentical versus HLA-matched sibling transplantation for refractory acute leukemia undergoing sequential intensified conditioning followed by DLI: an analysis from two prospective data

BACKGROUND

Compared with HLA-matched sibling donor (MSD) transplant, the outcomes of haploidentical donor (HID) transplant for refractory acute leukemia need to be further explored. In this study, we compared the outcomes of HID with MSD for refractory acute leukemia.

PATIENTS AND METHODS

This study population came from two prospective multicenter trials (NCT01883180, NCT02673008). Two hundred and seventy-eight patients with refractory acute leukemia were enrolled in this study, including 119 in HID group and 132 in MSD group. Sequential intensified conditioning was employed in all patients, and donor lymphocyte infusion (DLI) was administered in patients in the absence of active GVHD and according to minimal residual disease (MRD) from day + 60 post-transplantation for preventing relapse.

RESULTS

The complete remission of leukemia by day + 30 post-transplant were 94% and 93%, respectively, in HID and MSD groups (p = .802). The 1-year incidence of grades II-IV acute GVHD was 62% and 54% (p = .025), and 3-year incidence of chronic GVHD was 55% and 55% (p = .789), respectively, in two groups. HID transplant had lower incidence of first episode of MRD positivity and relapse than MSD transplant (28% vs 45%, p = .006; 26% vs 38%, p = .034). There was higher infection-related mortality in HID than MSD (8% vs 2%, p = .049) within the first 100 days' post-transplant. The 5-year overall survival was 46% and 42% (p = .832), respectively; the 5-year disease-free survival was 43% and 39% (p = .665), in HID and MSD groups, respectively.

CONCLUSIONS

HID transplant has lower relapse, but higher infection-related mortality and similar survival rates in refractory acute leukemia by the strategy of sequential intensified conditioning followed by DLI compared with MSD transplant.

Perspectives on the Use of a Medium-Dose Etoposide, Cyclophosphamide, and Total Body Irradiation Conditioning Regimen in Allogeneic Hematopoietic Stem Cell Transplantation: The Japanese Experience from 1993 to Present

The outcome for adults with acute lymphoblastic leukemia (ALL) treated with chemotherapy or autologous hematopoietic stem cell transplantation (HSCT) is poor. Therefore, allogeneic HSCT (allo HSCT) for adults aged less than 50 years with ALL is performed with myeloablative conditioning (MAC) regimens. Among the several MAC regimens, a conditioning regimen of 120 mg/kg (60mg/kg for two days) cyclophosphamide (CY) and 12 gray fractionated (12 gray in six fractions for three days) total body irradiation (TBI) is commonly used, resulting in a long term survival rate of approximately 50% when transplanted at the first complete remission. The addition of 30 mg/kg (15 mg/kg for two days) etoposide (ETP) to the CY/TBI regimen revealed an excellent outcome (a long-term survival rate of approximately 80%) in adults with ALL, showing lower relapse and non-relapse mortality rates. It is preferable to perform allo HSCT with a medium-dose ETP/CY/TBI conditioning regimen at the first complete remission in high-risk ALL patients and at the second complete remission (in addition to the first complete remission) in standard-risk ALL patients. The ETP dose and administration schedule are important factors for reducing the relapse and non-relapse mortality rates, preserving a better outcome. The pharmacological study suggests that the prolonged administration of ETP at a reduced dose is a promising treatment.

Factors associated with durable EFS in adult B-cell ALL patients achieving MRD-negative CR after CD19 CAR T-cell therapy

Autologous T cells engineered to express a CD19-specific chimeric antigen receptor (CAR) have produced impressive minimal residual disease-negative (MRD-negative) complete remission (CR) rates in patients with relapsed/refractory B-cell acute lymphoblastic leukemia (B-ALL). However, the factors associated with durable remissions after CAR T-cell therapy have not been fully elucidated. We studied patients with relapsed/refractory B-ALL enrolled in a phase 1/2 clinical trial evaluating lymphodepletion chemotherapy followed by CD19 CAR T-cell therapy at our institution. Forty-five (85%) of 53 patients who received CD19 CAR T-cell therapy and were evaluable for response achieved MRD-negative CR by high-resolution flow cytometry. With a median follow-up of 30.9 months, event-free survival (EFS) and overall survival (OS) were significantly better in the patients who achieved MRD-negative CR compared with those who did not (median EFS, 7.6 vs 0.8 months; P < .0001; median OS, 20.0 vs 5.0 months; P = .014). In patients who achieved MRD-negative CR by flow cytometry, absence of the index malignant clone by IGH deep sequencing was associated with better EFS (P = .034). Stepwise multivariable modeling in patients achieving MRD-negative CR showed that lower prelymphodepletion lactate dehydrogenase concentration (hazard ratio [HR], 1.38 per 100 U/L increment increase), higher prelymphodepletion platelet count (HR, 0.74 per 50 000/μL increment increase), incorporation of fludarabine into the lymphodepletion regimen (HR, 0.25), and allogeneic hematopoietic cell transplantation (HCT) after CAR T-cell therapy (HR, 0.39) were associated with better EFS. These data allow identification of patients at higher risk of relapse after CAR T-cell immunotherapy who might benefit from consolidation strategies such as allogeneic HCT. This trial was registered at www.clinicaltrials.gov as #NCT01865617.

Photochemotherapy and Graft-versus-Leukemia Reaction in Acute Leukemia: Tumor Immunity and Survival Are Dependent on Timing of Photochemotherapy of the Skin

BACKGROUND

Cure of acute leukemia after transplantation is mediated by the grafted cells. We investigated the graft-versus-leukemia effect (GVL) in patients with cutaneous acute graft-versus-host disease (GVHD) treated with photochemotherapy (psoralen and ultraviolet light type A).

METHOD

Forty-seven patients with acute leukemia were followed 5,000 days after transplantation to assess survival and GVL by multivariate analysis. The primary predictor was time to treatment of cutaneous acute GVHD by photochemotherapy separated into treatment start during the first week of acute GVHD versus after the first week of acute GVHD.

RESULTS

Photochemotherapy started after the first week of acute GVHD predicted GVL with a hazard ratio (HR) of 3.94 (95% confidence interval, CI, 1.67-9.33, p = 0.0018) and survival with preserved GVL with an HR of 2.63 (95% CI 1.30-5.32, p = 0.007). The effects on GVL and survival with preserved GVL were present regardless of whether the patients were transplanted in remission or relapse (p < 0.05). Chronic GVHD came earlier in the group that started photochemotherapy after 1 week of acute GHVD, but chronic GVHD did not increase the GVL.

CONCLUSION

The timing of photochemotherapy after cutaneous acute GVHD may direct the GVL and predict long-term leukemia-free survival.

The need for endodontic treatment and systemic characteristics of hematopoietic stem cell transplantation patients

The aim of this study is to investigate the relationship between the epidemiological and clinical profiles of patients before and after hematopoietic stem cell transplantation (HSCT) and the need for endodontic treatment. The subjects included 188 individuals enrolled in the dental care program for transplanted patients of the School of Dentistry, Federal University of Minas Gerais (Faculdade de Odontologia da Universidade Federal de Minas Gerais, FO-UFMG) from March 2011 through March 2016. The patients were subjected to an HSCT conditioning dental regimen based on a thorough clinical and radiographic evaluation. Intraoral periapical and bite-wing X-rays were obtained, and after evaluation, specific dental treatment was planned and performed. The following demographic and clinical data were collected from the patients' medical records: age, gender, transplantation stage, primary disease, transplant type, medication used, complete blood count at the time of visit, and need for endodontic treatment. The Kolmogorov-Smirnov and the chi-square tests were used. Leukemia (31.3%) and multiple myeloma (17.9%) were the most prevalent primary diseases. Most patients were subjected to allogeneic-related transplantation (83.6%). Most patients exhibited platelet counts and hemoglobin concentrations below the reference values in the pre-transplantation stage, while the neutrophil and platelet counts and the hemoglobin levels were within the reference ranges in the post-transplantation stage. The proportions of individuals requiring endodontic treatment were similar between the pre- and post-transplantation groups: 24.3% and 24.7%, respectively. The systemic conditions of the patients referred for dental treatment were compromised.

Isolated extramedullary cutaneous relapse despite concomitant severe graft-vs.-host disease and tissue chimerism analysis in a patient with acute lymphoblastic leukemia after allogeneic hematopoietic stem cell transplantation: A case report

Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is a potentially curative treatment option for patients with acute lymphoblastic leukemia (ALL). The curative potential of allo-HSCT for ALL is, in part, due to the graft-vs.-leukemia (GVL) effect, in addition to the intensive conditioning chemo-radiotherapy. However, relapse remains the major cause of treatment failure following allo-HSCT for ALL. In the allo-HSCT setting, testing for genetic markers of hematopoietic chimerism has become a part of the routine diagnostic program. Routine chimerism analysis is usually performed in peripheral blood or bone marrow; in fact, little is known about the value of tissue chimerism in patients with extramedullary relapse (EMR) after the allo-HSCT setting. The present study reports on, a case of a patient with ALL who experienced isolated cutaneous EMR despite ongoing graft-vs.-host disease (GVHD), and the results of peripheral blood and skin tissue chimerism studies using multiplex polymerase chain reaction (PCR) of short tandem repeats (STR-PCR). The present case demonstrates that, although complete remission and/or chimerism may be achieved in the bone marrow, chimerism achieved at the tissue level, and the subsequent GVL effect, may be limited, despite concomitant severe GVHD following allo-HSCT. Our tissue chimerism analysis results provide a good example of how skin tissue may be a ‘sanctuary’ site for effector cells of GVL, despite active GVHD and complete hematopoetic chimerism.

Comparison of outcomes of idarubicin intensified TBI-CY and traditional TBI-CY conditioning regimen for high-risk acute lymphoblastic leukemia undergoing allogeneic hematopoietic stem cell transplantation: A single center experience

High-risk acute lymphoblastic leukemia (ALL) carries a very poor prognosis, even after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Exploring novel conditioning regimen to more effectively eliminate leukemic clone while not alter transplant-related mortality (TRM) has become focus of attention. We retrospectively evaluated outcomes of 87 high-risk ALL patients undergoing allo-HSCT: 47 patients received idarubicin (IDA) intensified TBI-CY and 40 patients received traditional TBI-CY regimen. In IDA intensified group, patients received TBI (8Gy) on day-8, IDA of 15mg/m2/d from day-6 to -5, followed by CY (60mg/kg/d) on day-3 to -2. The cumulative incidence of relapse was significantly lower in IDA intensified group compared with TBI-CY group (P=0.018). Oropharyngeal mucositis was observed more frequent in IDA intensified group (P=0.013), while not followed by increased TRM. Very high-risk ALL patients benefit from IDA intensified regimen with only two of eight patients in no remission (NR) pre-transplantation and two of twelve ph+ALL patients relapsed after transplantation. After a median follow-up for all survivors of 21 months (range, 12-53 months), 2-year estimated OS and DFS was 66.2% vs 45.3% (P=0.031) and 62.5% vs 43.5% (P=0.044), respectively. In conclusion, IDA intensified TBI-CY regimen may reduce relapse while not increasing TRM, providing better survival for high-risk ALL patients undergoing allo-HSCT.

Allogeneic hematopoietic stem cell transplantation in adult acute lymphoblastic leukemia: potential benefit of medium-dose etoposide conditioning

The outcomes of adult acute lymphoblastic leukemia (ALL) patients with chemotherapy or autologous hematopoietic stem cell transplantation (HSCT) are unsatisfactory. Therefore, allogeneic (allo) HSCT has been applied to those patients in first complete remission (CR1), and has shown a long-term survival rate of approximately 50 %. In terms of myeloablative conditioning (MAC) regimen, higher dose of cyclophosphamide (CY) and total body irradiation (TBI) (the standard CY + TBI) has been generally applied to allo HSCT. Other MAC regimens such as busulfan-based or etoposide-based regimens have also been used. Among those, medium-dose etoposide (ETP) in addition to the standard CY + TBI conditioning regimen appears to be promising for allo HSCT in adult ALL when transplanted in ALL patients aged under 50 years in CR1 and also in CR2, showing an excellent outcome without increasing relapse or transplant-related mortality (TRM) rates. By contrast, reduced-intensity conditioning (RIC) regimens have also been applied to adult ALL patients and favorable outcomes have been obtained; however, relapse and TRM rates remain high. Therefore, an allo HSCT conditioning regimen which deserves further study for adult ALL patients aged under 50 years in CR1 and CR2 appears to be medium-dose ETP + CY + TBI and RIC is suitable for patients aged over 50 years or for younger patients with comorbid conditions. On the contrary, new therapeutic strategies for adult ALL patients are increasingly utilized with better outcomes; namely, various tyrosine kinase inhibitors for Philadelphia chromosome (Ph)-positive ALL, human leukocyte antigen-haploidentical HSCT, and pediatric-inspired regimens for Ph-negative ALL. Therefore, the optimal treatment modality should be selected considering patient’s age, Ph-positivity, donor availability, risk classification, efficacy, and safety.

Unmanipulated Haploidentical Reduced-Intensity Stem Cell Transplantation Using Fludarabine, Busulfan, Low-Dose Antithymocyte Globulin, and Steroids for Patients in Non-Complete Remission or at High Risk of Relapse: A Prospective Multicenter Phase I/II Study in Japan

This prospective, multicenter phase I/II study of unmanipulated HLA-haploidentical reduced-intensity stem cell transplantation using a low dose of anti-T lymphocyte globulin (ATG) and steroid was conducted in 5 institutions in Japan. Thirty-four patients with hematologic malignancies who were in an advanced stage or at a high risk of relapse at the time of transplantation were enrolled. Among them, 7 patients underwent transplantation as a second transplantation because of relapse after the previous allogeneic stem cell transplantation. The conditioning regimen consisted of fludarabine, busulfan, and ATG (Fresenius, 8 mg/kg), and graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus and methylprednisolone (1 mg/kg). All patients except 1 (97.1%) achieved donor-type engraftment. Rapid hematopoietic engraftment was achieved, with neutrophils > .5 × 10(9)/L on day 11 and platelets > 20 × 10(9)/L on day 17.5. Treatment was started for ≥grade I GVHD, and the cumulative incidences of acute grade I and grade II to IV GVHD were 27.5% and 30.7%, respectively. The incidence of chronic GVHD (extensive type) was 20%. Fourteen patients (41.2%) had a relapse. The cumulative incidence of transplantation-related mortality at 1 year after transplantation was 26.5%. The survival rate at day 100 was 88.2%. The survival rates at 1 year for patients with complete remission (CR)/chronic phase (n = 8) and non-CR (n = 26) status before transplantation were 62.5% and 42.3%, respectively. In the multivariate analysis, non-CR status before transplantation was the only factor significant prognostic factor of increased relapse (P = .0424), which tended to be associated with a lower survival rate (P = .0524). This transplantation protocol is safe and feasible, if a suitable donor is not available in a timely manner. As the main cause of death was relapse and not GVHD, more intensified conditioning or attenuation of GVHD prophylaxis and/or donor lymphocyte infusion may be desirable for patients with non-CR status.

A Safety and Efficacy Study of Medium-Dose Etoposide, Cyclophosphamide and Total Body Irradiation Conditioning Before Allogeneic Stem Cell Transplantation for Acute Lymphoblastic Leukemia

Prognosis for adult patients with acute lymphoblastic leukemia (ALL) has been reported to be approximately 35% to 50%, even after allogeneic stem cell transplantation (allo-SCT). We previously reported retrospective analyses of a conditioning regimen of medium-dose etoposide, cyclophosphamide (CY), and total body irradiation (TBI) before allo-SCT for ALL. To prospectively analyze the efficacy of this conditioning regimen, we conducted a trial prospectively.

Role of allogeneic hematopoietic stem cell transplantation in adult patients with acute lymphoblastic leukemia

Adult acute lymphoblastic leukemia (ALL) is a heterogeneous disease, due to the expression of different biological and clinical risk factors, for which allogeneic stem cell transplantation (alloHSCT) is an effective consolidation therapy. The non-relapse mortality of alloHSCT remains significantly higher compared with that of conventional chemotherapy. Therefore, one of the main challenges in the care of ALL is to establish a more precise prognostic definition to select patients who could take advantage from an alloHSCT. Currently, the use of minimal residual disease following induction and early consolidation therapy has improved the prognostic accuracy in defining ALL risk class. In Philadelphia-positive ALL, the introduction of tyrosine kinase inhibitors pre and post alloHSCT appears to improve outcomes significantly and, in the absence of specially designed clinical trials, alloHSCT remains the most effective post-remission therapy. Nowadays, alloHSCT can be performed according to various modalities encompassing the use of different conditioning regimens, as well as distinct donors and stem cell source, with a significant accessibility to transplant.

Allogeneic hematopoietic stem cell transplantation in adolescent and adult patients with high-risk T cell acute lymphoblastic leukemia

Allogeneic hematopoietic stem cell transplantation (allo-SCT) is often recommended for patients with T cell acute lymphoblastic leukemia (T-ALL) in second or later complete remission (≥CR2) and sometimes in high-risk (HR) patients in first complete remission (CR1). Between January 1995 and July 2009, 53 patients with HR T-ALL underwent allo-SCT at our institution. Median age was 18 years (range, 14-51). Thirty-two patients (60.3%) were in CR1, 18 (34%) were in ≥CR2, and 3 (5.7%) were in relapse. The cumulative incidence of nonrelapse mortality at 5 years was 22.5%. The cumulative incidence of grade II-IV acute graft-versus-host disease (GVHD) was 40.2%, and that of chronic GVHD was 43.7%. The majority of relapses (88.9%) occurred within 1 year after SCT. The cumulative incidence of relapse (CIR) at 5 years was 35.6%. CIR was 29.8% in patients in CR1, 35.3% in patients in ≥CR2 and all patients transplanted in relapse had disease recurrence post-allo-SCT (P = .000). Overall survival (OS) and disease-free survival (DFS) at 5 years were 43.5% and 41.8%, respectively. The 5-year OS was 53.5% (95% CI 34.5%-72.5%) and 5-year DFS was 52% (95% CI 33%-71%) in patients who underwent allo-SCT in CR1, compared with 31.9% (95% CI, 9%-54.8%) and 29.4% (95% CI 7.6%-51.2%) in those who underwent allo-SCT in ≥CR2. On multivariate analysis, disease status at SCT remained significantly associated with OS (P = .007), DFS (P = .002), and CIR (P = .000). The presence of extramedullary disease at diagnosis had no effect on the different outcomes. Grade II-IV acute GVHD was significantly associated with a lower OS (P = .006) and DFS (P = .01). Our data indicate that allo-SCT represents an effective treatment for HR T-ALL, particularly when performed in CR1.

The role of allogeneic hematopoietic stem cell transplantation in the therapy of patients with acute lymphoblastic leukemia

Allogeneic hematopoietic stem cell transplantation (alloHSCT) is an effective post-remission therapy in patients with acute lymphoblastic leukemia (ALL), but is associated with significant toxicity, so the optimal timing and use of this modality remains an issue of debate. Increased advances in reduced-intensity transplant preparative regimens and alternative donors has increased the accessibility of allogeneic transplantation. A risk adapted paradigm, using minimal residual disease analysis, may help in the selection of patients at highest risk for relapse, who may benefit most from alloHSCT. In this review, we summarize the indications for allogeneic transplantation within the risk-oriented paradigm, and also explore the latest literature on reduced intensity transplant regimens, as well as alternative donor transplantation for patients with ALL.

Safety and efficacy of total body irradiation, cyclophosphamide, and cytarabine as a conditioning regimen for allogeneic hematopoietic stem cell transplantation in patients with acute lymphoblastic leukemia

Disease relapse still greatly interferes with the success of allogeneic hematopoietic stem cell transplantation (HSCT) for acute lymphoblastic leukemia (ALL). This study retrospectively evaluated the long-term safety and efficacy of a conditioning regimen consisting of total body irradiation (TBI; 12 Gy), cyclophosphamide (CY; 60 mg kg(-1) , two doses), and high-dose cytarabine (Ara-C; 2 g m(-2) ; four doses) for patients with ALL. Fifty-five patients (median age: 31-years old) were evaluated. Stem cells were from human leukocyte antigen-identical siblings in 22 patients and from alternative donors in 33. There were no cases of early death before engraftment, and 100-day transplant-related mortality was 7.3%. With a median follow-up period of 9.6 years, 5-year overall and disease-free survival were 63.2% (95% CI: 46.5-79.9%) and 63.6% (95% CI: 47.1-80.1%) in patients with complete remission, respectively, both of which were significantly higher than the values of 27.3% (95% CI: 8.7-46.0%) and 22.7% (95% CI: 5.3-40.1%) for patients in advanced stages (P < 0.01). These results suggest that TBI and CY (TBI-CY) plus Ara-C could be a feasible and effective conditioning regimen for adult patients with ALL both in remission and in advanced stages, and a future study to compare this combination therapy with TBI-CY is required.

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 with full-intensity conditioning for adult acute lymphoblastic leukemia: results from a single center, 1998-2006

A retrospective analysis identified 161 consecutive adults with acute lymphoblastic leukemia who underwent allogeneic hematopoietic cell transplantation (HCT) with full-intensity (myeloablative) conditioning between 1998 and 2006. Median patient age was 36.1 years. Seventy-six patients were in first complete remission (CR1), and 85 were in second or greater CR or in relapse. Fifty-nine patients had Philadelphia chromosome-positive acute lymphoblastic leukemia. A total of 159 patients received chemotherapy plus total body irradiation for conditioning. Graft-versus-host disease prophylaxis included a calcineurin inhibitor plus methotrexate or mycophenolate mofetil. Sixty of the donors were related, and 101 were unrelated. A total of 110 patients received granulocyte-colony stimulating factor-stimulated peripheral blood, 47 received bone marrow, and 4 received cord blood as the stem cell source. Fifty-five patients relapsed at a median of 231 days after transplantation. The estimated 5-year probabilities of relapse-free survival, relapse, and nonrelapse mortality were 47%, 30%, and 29%, respectively. By multivariate analyses, transplantation while in CR1 was the most important predictor of successful transplantation. Pretransplantation evidence of minimal residual disease, especially as detected by flow cytometric analysis, was associated with both lower overall survival and lower relapse-free survival. Compared with a similar cohort of patients undergoing transplantation between 1990 and 1997, overall survival was similar for patients undergoing transplantation in CR1, with lower nonrelapse mortality being offset by higher rates of relapse in patients who underwent transplantation more recently.

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.

Outcome of hematopoietic stem cell transplantation of children with very high risk acute lymphoblastic leukemia in first complete remission

Approximately 10% of children with ALL present at diagnosis with VHR for relapse if treated with chemotherapy alone. They may benefit from allogeneic HSCT in CR1. We have reviewed the outcome of this population in our institution. Forty-three patients (median age: 8.9 yr) with VHR ALL in CR1 underwent HSCT from October 1994 to April 2006. VHR features included Philadelphia chromosome (n = 17), induction failure (n = 9), hypodiploidy (n = 6), MLL gene rearrangement (n = 5), and others (n = 6). All patients received TBI (1200 cGy) with either CY and/or etoposide. Stem cell source was unrelated (n = 24) and related (n = 19). Incidence of grade III-IV acute GVHD and chronic extensive GVHD were 25% and 16%, respectively. Twelve patients relapsed (eight received related HSCT). Eleven patients died due to transplant-related mortality (eight received unrelated HSCT). For a median follow up of 39 months (range 11-110), the event free survival and OS were 0.49 (95% CI: 0.31-0.67) and 0.53 (CI: 0.44-0.71), respectively. Outcomes of children with VHR ALL receiving HSCT in CR1 remain unsatisfactory. Relapse, mainly after related HSCT, and TRM, mainly after unrelated HSCT, continue to be major problems.

Unrelated transplantation for poor-prognosis adult acute lymphoblastic leukemia: long-term outcome analysis and study of the impact of hematopoietic graft source

Adults with high-risk acute lymphoblastic leukemia (HR-ALL) have a poor outcome with standard chemotherapy and usually undergo unrelated stem cell transplantation (SCT) if a matched sibling donor is not available. We analyzed the outcome of adult patients with unrelated SCT for HR-ALL and studied the possible effect of the hematopoietic stem cell source of the transplant. A total of 149 adult patients (median age, 29 years, range, 15-59 years) with HR-ALL underwent unrelated SCT in 13 Spanish institutions between 2000 and 2007. Patients in first complete remission (CR1) at transplantation had at least one adverse prognostic factor (advanced age, adverse cytogenetics, hyperleukocytosis, or slow response to induction therapy). ALL was in CR1 in 81 patients (54%), in second CR (CR2) in 37 patients (25%), in third CR (CR3) in 11 patients (7%), and with overt disease in 20 patients (13%). The hematopoietic source was unrelated cord blood (UCB) in 62 patients and an unrelated donor (UD) in 87 patients. The patients undergoing UCB-SCT and UD-SCT were comparable in terms of the main clinical and biological features of ALL, except for a higher frequency of patients with more overt disease in the UCB-SCT group. There was no statistically significant difference in overall survival (OS) or disease-free survival (DFS) at 5 years between the 2 groups. Treatment-related mortality (TRM) was significantly lower in the UCB-SCT group (P = .021). The probability of relapse at 1 year was 17% (95% confidence interval [CI], 7%-27%) for the UD-SCT group and 27% (95% CI, 14%-40%) for the UCB-SCT group (P = .088), respectively. Only disease status at transplantation (CR1, 41% [95% CI, 18%-64%] vs CR2, 51% [95% CI, 17%-85%] vs advanced disease, 66% [95% CI, 46%-86%]; P = .001) and the absence of chronic graft-versus-host disease (74% [95% CI, 46%-100%] vs 33% [95% CI, 17%-49%]; P = .034) were significant factors for relapse. All unrelated transplantation modalities were associated with high treatment-related mortality for adult HR-ALL patients without a sibling donor. UCB-SCT and UD-SCT were found to be equivalent options. Disease status at transplantation and chronic GVHD were the main factors influencing relapse in both transplantation modalities.

A modified EBMT risk score and the hematopoietic cell transplantation-specific comorbidity index for pre-transplant risk assessment in adult acute lymphoblastic leukemia

BACKGROUND

Disease stage is the most important prognostic parameter in allogeneic hematopoietic cell transplantation (HCT) for acute lymphoblastic leukemia, but other factors such as donor/host histocompatibility and gender combination, recipient age, performance status and comorbidities need to be considered. Several scoring systems are available to predict outcome in HCT recipients; however, their prognostic relevance in acute lymphoblastic leukemia is not well defined.

DESIGN AND METHODS

In the present study we evaluated a modified EBMT risk score (mEBMT) and the HCT-specific comorbidity index (HCT-CI) in 151 adult acute lymphoblastic leukemia patients who received allogeneic HCT from 1995 until 2007 at our center.

RESULTS

Disease status was first complete remission (CR1) (47%), CR>1 (21%) or no CR (32%). Overall survival (OS) at one, two and five years was 62%, 51% and 40% and non-relapse mortality (NRM) was 21%, 24% and 32%. Median mEBMT was 3 (0-6). Higher mEBMT was associated with inferior OS (hazard ratio per score unit (HR): 1.50, P<0.001), higher NRM (HR: 1.36, P=0.042) and higher relapse mortality (HR: 1.68, P<0.001). Disease stage was the predominant prognostic factor in this score. Comorbidities were present in 71% of patients with mild hepatic disease (29%), moderate pulmonary disease (28%) and infections (23%) being the most common. Median HCT-CI was 1 (0-9). In univariate analysis a trend for inferior OS (HR: 1.08, P=0.20) and higher NRM (HR: 1.14, P=0.11) with increasing HCT-CI was observed but the level of significance was not reached. In additional analyses we found that reduced Karnofsky Performance Status (KPS) was associated with inferior OS (HR: 1.34, P=0.023) and higher relapse mortality (HR: 1.71, P=0.001) when analyzed univariately. However, KPS was associated with disease stage and significance was lost in multivariate analysis.

CONCLUSIONS

The mEBMT was prognostic in our patient cohort with predominant influence of disease stage, whereas a trend but no significant prognostic value was observed for the HCT-CI.

Cytomegalovirus infection in children undergoing hematopoietic stem cell transplantation in Chile

BACKGROUND

Cytomegalovirus (CMV) infection remains as an important cause of morbidity and mortality in children undergoing hematopoietic stem cell transplantation (HSCT). Our aim was to assess the incidence, risk factors, and outcome related to CMV infection in children after HSCT in a developing country.

METHODS

From October 1, 1999, to December 31, 2005, we prospectively studied all patients admitted to the HSCT unit at Hospital Luis Calvo Mackenna in Santiago, Chile. Serologic studies before transplantation and weekly CMV infection surveillance (antigenemia or quantitative PCR) were routinely obtained. Patients with positive antigenemia or quantitative PCR received pre-emptive therapy with ganciclovir, and cases of unfavorable clinical evolution, persistent positive antigenemia, or quantitative PCR after 14 days of ganciclovir were treated with foscarnet.

RESULTS

Ninety-seven patients received HSCT. Their median age was 8 years (range, 3 months to 24 years) and their overall survival was 67%. CMV reactivation was diagnosed in 26 patients. Of these, three developed CMV disease (two interstitial pneumonia, one hemorrhagic cystitis). One of the patients with pneumonia died. Risk factors identified were pre-transplant serologic status (positive recipient), acute and chronic graft versus host disease (GvHD), GvHD prophylaxis, and treatment with antithymocyte globulin.

CONCLUSIONS

The rate and prognosis of CMV infection among children treated at our HSCT unit is similar to those reported from industrialized countries. These findings reflect adequate prevention and management of CMV infection within our program.

Sequential intensified conditioning and tapering of prophylactic immunosuppressants for graft-versus-host disease in allogeneic hematopoietic stem cell transplantation for refractory leukemia

For patients with advanced leukemia undergoing allogeneic hematopoietic stem cell transplantation (allo-HSCT), a major obstacle to success, especially in those with a high leukemia cell burden, is relapse of the underlying disease. To improve the outcome of allo-HSCT for refractory leukemia, we investigated the strategy of sequential intensified conditioning and early rapid tapering of prophylactic immunosuppressants therapy for graft-versus-host disease (GVHD) during the early stage after transplantation. A total of 51 patients with refractory leukemia (median age, 30.0 years; unfavorable karyotypes, 49%) received fludarabine (Flu) 30 mg/m(2)/day and cytarabine 2 g/m(2)/day (on days -10 to -6), 4.5 Gy total body irradiation (TBI)/day (on days -5 and -4), and cyclophosphamide (Cy) 60 mg/kg/day and etoposide 600 mg/day (on days -3 and -2) for conditioning. Cyclosporine A (CsA) was withdrawn rapidly in a stepwise fashion to avoid overwhelming GVHD reactions if acute GVHD (aGVHD) did not develop at day +30. All 51 patients developed regimen-related toxicities (13 with grade III-IV); 93.9% of them achieved complete remission by day +30. Median follow-up was 41 months (range, 6.6 to 92.2 months); 5-year overall survival (OS) and disease-free survival (DFS) were 44.6% +/- 8.1% and 38.2% +/- 7.7%, respectively. Thirteen patients relapsed; the 3-year cumulative incidence of leukemia relapse was 33.3%. On multivariate analysis, cytogenetic status was the only significant pretransplantation factor. Survival was better in patients with grade I or II aGVHD than in those without aGVHD. Our data indicate that the sequential strategy of cytoreductive chemotherapy followed immediately by intensified myeloablative (MA) conditioning for allo-HSCT and rapid tapering of prophylactic immunosuppressants for GVHD in the early stage after transplantation has an acceptable toxicity profile and may be a better approach to treating refractory leukemia.

Management of Philadelphia chromosome–positive acute lymphoblastic leukemia (Ph+ ALL)

The tyrosine kinase inhibitor (TKI) imatinib has become an integral part of front-line therapy for Ph+ ALL, with remission rates exceeding 90% irrespective of whether imatinib is given alone or combined with chemotherapy. Treatment outcome with imatinib-based regimens has improved compared with historic controls, but most patients who do not undergo allogeneic stem cell transplantation (SCT) eventually relapse. Acquired resistance on TKI treatment is associated with mutations in the bcr-abl tyrosine kinase domain in the majority of patients, and may be detected at low frequency prior to TKI treatment in a subset of patients. Second generation TKIs, eg, dasatinib and nilotinib, show activity against most of the bcr-abl tyrosine kinase domain (TKD) mutations involved in acquired imatinib resistance, but clinical benefit is generally short-lived. Accordingly, SCT in first complete remission (CR) is considered to be the best curative option. Molecular monitoring of minimal residual disease levels appears to have prognostic relevance and should be used to guide treatment. International standardization and quality control efforts are ongoing to ensure comparability of results. Mutation analysis during treatment relies increasingly on highly sensitive PCR techniques or denaturing HPLC and may assist in treatment decisions, eg, in case of molecular relapse. Results from current studies of second-generation TKI as front-line treatment for Ph+ ALL are promising and show high molecular response rates, but follow-up is still too short to determine their impact on remission duration and long-term survival. Strategies to improve outcome after SCT include the pre-emptive use of imatinib, which appears to reduce the relapse rate. In patients ineligible for transplantation, novel concepts for maintenance therapy are needed. These could involve novel immunotherapeutic interventions and combinations of TKI.

Transplantation in adult ALL

The value of the allogeneic graft-versus-leukemia effect in adult acute lymphoblastic leukemia (ALL) has now been conclusively demonstrated and confirmed. While this is true for adults in all age groups, it may not be the best clinical option for young adults for whom increasingly intensive pediatric protocols are clearly of benefit. On the other hand, there is potentially wider applicability of allogeneic donor transplantation for adults 25 to 45 years old, for whom matched unrelated donors may be as safe and effective as sibling donors, and for the patient older than 45 years for whom reduced-intensity conditioning may be a promising way forward. Since the treatment-related mortality of allogeneic transplantation remains significant, careful selection of patients is mandatory. Patients with the Philadelphia chromosome, those with t(4;11) and those with a complex karyotype remain transplant candidates, and allogeneic transplantation remains the best option for salvage, where achievable, in a remission beyond first. As in childhood ALL minimal residual disease studies may be extremely useful in predicting outcome and, therefore, strategy, but at present there are less definite data in adults. Clinical indications to harness the allogeneic effect will mature as the true value of pediatric protocols in adult patients and the safety and efficacy of a sibling, unrelated and reduced intensity transplant emerge in this disease.

Prognostic factors of survival time after hematopoietic stem cell transplant in acute lymphoblastic leukemia patients: Cox proportional hazard versus accelerated failure time models

Background

The aim of this study is to evaluate the prognostic factors of overall survival (OS) after haematopoietic stem cell transplant (HSCT) in acute lymphoblastic leukaemia (ALL) patients using accelerated failure time (AFT), Cox proportional hazard (PH), and Cox time-varying coefficient models.

Methods

206 patients were enrolled after HSCH in Shariati Hospital between 1993 and 2007. There was evidence of marked departures from the proportional hazards assumption with two prognostic factors, relapse and chronic graft-versus-host disease (cGVHD) (P < .001). Performance among AFT and Cox's models was assessed using explained variation and goodness of fit methods. Discrimination among the exponential, Weibull, generalized gamma (GG), log-logistic, and lognormal distributions was done using maximum likelihood and Akaike information criteria.

Results

The 5-year OS was 52% (95%CI: 47.3–56.7). Peak mortality hazard occurred at months 6–7 after HSCT followed by a decreasing trend. In univariate analysis, the data was better fitted by GG distribution than by other distributions. Univariate analysis using GG distribution showed a positive association between OS with acute graft-versus-host disease (aGVHD) (P = .021), no relapse (P < .001), cGVHD (P < .001), neutrophil recovery (P < .001) and platelet recovery (P < .001). Based on Cox PH models; however cGVHD and relapse were the predictive factors of OS (P < .001). Multivariate analysis indicated that, OS is related to relapse (P < .001) and platelet recovery (P = .037), where predictive power of Weibull AFT models was superior to Cox PH model and Cox with time-varying coefficient (R² = 0.46 for AFT, R² = .21 for Cox PH and R² = .34 for Cox time-varying coefficient). Cox-Snell residual shows Weibull AFT fitted to data better than other distributions in multivariate analysis.

Conclusion

We concluded that AFT distributions can be a useful tool for recognizing prognostic factors of OS in acute lymphoblastic leukemia patients.

Allogeneic SCT in refractory or relapsed adult ALL is effective without prior reinduction chemotherapy

We present 60 patients with refractory (n=8) or relapsed (n=52) adult ALL who received allogeneic hematopoietic SCT (HSCT) with (n=41) or without (n=19) prior reinduction chemotherapy. In our center, omission of reinduction is recommended if a suitable donor is promptly available, tumor burden is moderate and disease features suggest a highly aggressive course. Overall survival (OS) of the whole cohort at 1, 2 and 5 years was 42, 33 and 28%, respectively. Leukemia-free survival at 1, 2 and 5 years was 37, 33 and 24%. Deaths were due to relapse (n=25), acute or chronic GVHD (n=7), infections (n=8) or toxicity (n=4). Interestingly, patients who did not receive reinduction before HSCT had better outcomes than patients who received reinduction with OS at 1, 2 and 5 years being 58 vs 34%, 47 vs 25% and 47 vs 18%, respectively (P=0.039). Importantly, even achievement of a second CR after reinduction was not associated with improved survival compared to patients directly proceeding to HSCT. We conclude that patients who undergo HSCT for refractory or relapsed ALL can achieve long-term survival. In selected patients, reinduction chemotherapy can be omitted if immediate HSCT is feasible.

Excellent outcome of allogeneic hematopoietic stem cell transplantation using a conditioning regimen with medium-dose VP-16, cyclophosphamide and total-body irradiation for adult patients with acute lymphoblastic leukemia

We retrospectively evaluated the outcomes of 37 adult patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT) conditioned with medium-dose VP-16 (VP, 30 mg/kg), cyclophosphamide (CY, 120 mg/kg), and fractionated total-body irradiation (TBI, 12 Gy) (medium-dose VP/CY/TBI). The median age of the patients was 26 years. Thirteen patients underwent transplantation from HLA-matched related donors (MRD), 18 patients underwent transplantation from HLA-matched unrelated donors (MUD), and 6 patients underwent transplantation from HLA-mismatched donors (MMD). Thirty-two patients received bone marrow and 4 patients received peripheral blood stem cells. Ten patients were Philadelphia chromosome-positive (Ph(+)) and 35 patients were in complete remission (CR) at transplantation. All of the patients achieved engraftment, and grade 3 organ toxicity before engraftment occurred in 27 patients. Grade II-III acute graft-versus-host disease (GVHD) and chronic GVHD (cGVHD) occurred in 15 and 18 patients, respectively. No patient developed grade IV acute GVHD (aGVHD) or died of GVHD. At median follow-up of 35.1 months, 32 patients were alive and all Ph(+) patients were alive. Three patients died of relapse and 2 died of transplant-related mortality (TRM). The actuarial 3-year overall survival (OS) rate, relapse rate, and TRM rate were 89.2%, 8.1%, and 5.4%, respectively. Non-CR at transplantation, MRD, and no aGVHD were significant adverse prognostic factors for survival. Medium-dose VP/CY/TBI for adult ALL patients was associated with lower relapse rate and no increase in toxicity, resulting in better survival.

Lack of utility of chimerism studies obtained 2-3 months after myeloablative hematopoietic cell transplantation for ALL

Lineage-specific chimerism studies are commonly obtained at several time points after nonmyeloablative hematopoietic cell transplantation to assess the tempo and degree of engraftment, and to monitor graft rejection. For patients who receive myeloablative transplants, the value of frequent chimerism analyses using sensitive molecular techniques is less certain. In this study, a retrospective analysis was performed to assess the transplant outcome of 89 adult patients with ALL who had chimerism studies of unfractionated BM cells or peripheral blood subsets performed approximately 80 days after transplantation. These patients received unmanipulated, myeloablative transplants using either HLA-identical or HLA-mismatched, related or unrelated donor stem cells. Incomplete donor engraftment was present only in the CD3+ peripheral blood T cells in a small percentage of patients. There was no correlation of mixed chimerism with transplant outcome. Routine 'day 80' chimerism studies in this group of patients who receive intensive, myeloablative conditioning regimens are not recommended.

Allogeneic transplantation for ALL in adults

Allogeneic transplantation is an effective treatment for adult patients with high-risk ALL, including patients in first or second remission. Although only a few studies have evaluated the optimal transplant regimens, the data would suggest that a TBI-based regimen results in better disease control. Although not as potent as it is in other hematologic malignancies, the GVL effect is an important component of achieving cure of ALL. Because of the toxicity of the fully ablative regimen, reduced-intensity transplants are being explored in older patients with ALL when the prognosis is especially poor with standard chemotherapy.

Allogeneic Stem Cell Transplantation in First Complete Remission Enhances Graft-versus-Leukemia Effect in Adults with Acute Lymphoblastic Leukemia: Antileukemic Activity of Chronic Graft-versus-Host Disease

The aim of the present study was to identify graft-versus-leukemia effects and the factors that affect outcome in 201 adults with acute lymphobalstic leukemia who received myeloablative allogeneic stem cell transplantation from matched sibling or unrelated donors (1995-2004). One hundred seventy-eight (88.6%) of these patients had high-risk criteria, and 151 (75.1%) patients were transplanted in first complete remission (CR). All patients received unmodified stem cell grafts (185 bone marrow and 16 peripheral blood) following total- body irradiation-containing myeloablative preparations. Graft-versus-host disease (GVHD) prophylaxis was uniformly attempted by administering calcineurin inhibitor plus methotrexate. After a median follow-up of 63 months (range: 25+ to 139+ months) for surviving transplants, disease-free survival at 5 years was 47.8% for all patients and 60.3% for patients in the first CR. No difference in transplantation outcome was observed between sibling and unrelated transplants in the first CR. The most powerful predictive factor affecting transplantation outcome was disease status at transplantation (the first CR versus beyond the first CR, P<.001). Chronic GVHD (cGVHD), especially limited type, was also found to have a significant antileukemic effect. Interestingly, the influence of cGVHD on relapse risk was prominent in patients with chromosomal translocations or normal cytogenetics.

Non-HLA gene polymorphisms in stem cell transplantation

An increasing number of gene polymorphisms of immune regulatory molecules are being associated with clinical performance following stem cell transplantation (SCT). These polymorphisms affect structural or regulatory changes on immune regulatory molecules including cytokines . In contrast to polymorphisms of the major histocompatibility complex, the genome variations found in these non-human leukocyte antigen genes are simple to detect, allowing studies to be done in many laboratories and transplant centres. Many forms of DNA polymorphism detection are now available, allowing even modest laboratories to mount studies of their own. Despite these advances, studies in SCT have a number of problems relating to the complex clinical situation that they study; issues of study design and data interpretation in transplant studies are complex and challenging and are the main limiting factors, which inhibit progress in confirming genetic features which influence the success of SCT.

Non-myeloablative stem cell transplantation in patients with relapsed acute lymphoblastic leukemia: results of a multicenter study

Using non-myeloablative conditioning, allogeneic hematopoietic stem cell transplantation (HSCT) was conducted in 43 ALL patients in a CR2. The median age of the patients was 19 years. Patients received oral busulfan 4 mg/kg/day for 2 days; i.v. cyclophosphamide 350 mg/m(2)/day for 3 days; and i.v. fludarabine 30 mg/m(2)/day for 3 days. Oral cyclosporin A 4 mg/kg was started and methotrexate 5 mg/m(2) was delivered on days 1, 3, 5 and 11. The median CD34+ cell dose received was 5.0 x 10(6)/kg. The medium time to achieve a granulocyte count above 0.5 x 10(9)/l was 14 days. Thirteen patients were alive 30-1050 days after the HSCT. The 3-year overall survival rate was 30%. Ten patients (23%) developed acute GVHD, whereas eight patients (18.6%) developed chronic GVHD. Thirty patients died between days 47 and 1050 after the HSCT, most of them (70%) because of an ALL relapse. One hundred-day mortality was 15%, whereas transplant-related mortality was 21%. These results are inferior to those obtained using the same allografting method in other leukemias, probably as a consequence of poor susceptibility to the graft-versus-leukemia effect of the ALL cells beyond first remission as compared with other hematological malignancies.

Long-term results of allogeneic bone marrow transplantation for 108 adult patients with acute lymphoblastic leukemia: favorable outcome with BMT at first remission and HLA-matched unrelated donor

We analyzed the outcome of 108 adult acute lymphoblastic leukemia patients undergoing allogeneic bone marrow transplantation (BMT). Philadelphia (Ph) chromosome occurred in 35.2% patients at diagnosis. Two-thirds of patients received allogeneic BMT in first complete remission (CR1) BMT. Salvage BMT was performed in 21 and 16 patients at second complete remission (CR2) and beyond CR2. Donors were human leukocyte antigen-identical siblings in 87 patients, and match-unrelated donors in 21 patients. Conditioning contained total body irradiation (TBI) in 92.6% patients. Overall survival (OS) for BMT at CR1 and BMT beyond CR1 were 46.2 and 20.3% at 15 years. Multivariate analyses (including age, sex, disease status, donor type, acute graft-versus-host disease (aGVHD), stem cell source, cytogenetics, grade 1/2 aGVHD and TBI-containing conditioning regimen) identified age<35, BMT at CR1 and grade 1/2 aGVHD as favorable factors for OS. Disease-free survival (DFS) for BMT at CR1 and beyond CR1 were 45.8 and 15.9% at 15 years, respectively, with BMT at CR1, age<35 and grade 1/2 aGVHD being favorable factors for DFS. Importantly, conventional adverse risk factors such as the Ph chromosome, B-cell phenotype and high leukocyte count were not associated with inferior survivals. In summary, the adverse impact of Ph chromosome, B-cell phenotype and high leukocyte count was overcome by allogeneic BMT. Matched unrelated donor transplantation appears promising.

Intravenous Busulfan and Melphalan, Tacrolimus, and Short-Course Methotrexate Followed by Unmodified HLA-Matched Related or Unrelated Hematopoietic Stem Cell Transplantation for the Treatment of Advanced Hematologic Malignancies

Results of allogeneic hematopoietic stem cell transplantation (HCT) to treat advanced leukemia or myelodysplastic syndrome (MDS) remain poor due to excessive relapse and transplant-related mortality. To improve transplant outcome in this patient population, 43 patients (median age, 46.1 years) with high-risk or advanced lymphoid (n = 5) or myeloid malignancy (n = 38) were prospectively enrolled on a pilot trial of cytoreduction with intravenous busulfan and melphalan followed by an unmodified HLA-A, -B, and -DRbeta1-matched related (n = 18) or unrelated (n = 25) HCT. Graft-versus-host disease (GVHD) prophylaxis consisted of tacrolimus and methotrexate. Thirty-four patients had > or = 5% blasts at the time of HCT; 12 of these had > 20% blasts. Seventeen patients had unfavorable cytogenetics, 8 patients underwent transplantation for secondary MDS or acute myelogenous leukemia, and 4 patients had relapsed after a previous allogeneic transplantation. Although mucositis was the most significant regimen-related toxicity, requiring the addition of folinic acid rescue and failure to receive all 4 doses of methotrexate in 23 patients, the nonrelapse mortality at 30 and 100 days was low at 0% and 16%, respectively. The cumulative incidence of grade II-IV acute GVHD was 24%, and that of extensive chronic GVHD was 7%. With a minimum follow-up of 18 months, the estimated 3-year overall survival is 37% and the estimated disease-free survival (DFS) is 33%. For 18 patients with MDS (< or = RAEB-2) or high-risk myeloproliferative disorder, the estimated 3 year DFS is 61%. These data demonstrate the curative potential of this regimen in patients with high-risk myeloid malignancies.

Which Patients with Adult Acute Lymphoblastic Leukemia Should Undergo a Hematopoietic Stem Cell Transplantation? Case-Based Discussion

The decision to proceed to transplant for adult patients with acute lymphoblastic leukemia (ALL) is not clear-cut. Relapse and nonrelapse mortality continue to plague the outcome of hematopoietic stem cell transplantation (HSCT) even when undertaken in complete remission (CR). Those considered to be at high risk for relapse often are considered for HSCT in first complete remission (CR1) while those at lower risk may not be referred until they have relapsed, when their chances for cure are very poor. In some patients who have a suitable histocompatible sibling, disease- or patient-related factors may override the potential benefit of allogeneic HSCT. Because many patients do not have a suitable histocompatible sibling, one has to consider the relative merits of autologous transplantation versus use of an alternative allogeneic stem cell source, such as a matched-unrelated donor (MUD), umbilical cord blood (UCB) donor, or haploidentical donor. Deciding among these options in comparison to chemotherapy even in high-risk patients is difficult. In the review, the risks and benefits of these choices are discussed to determine whether and by what means to proceed to HSCT in adult patients with ALL who are in CR1. Presented are two patients with ALL and a discussion of how the data we provide would lead to a decision about the selection of therapy.

Treatment of Relapsed Acute Leukemia after Allogeneic Transplantation: A Single Center Experience

Relapsed acute leukemia after allogeneic transplantation has a poor prognosis and most reports have focused on the role of second transplantations in relapsed patients. We report our single-institution experience on the management of relapsed acute leukemia after allogeneic transplantation. We aimed to describe the outcome of relapsed acute leukemia after allogeneic transplantation at our institution and investigate whether maneuvers intended to augment donor T cell allogeneic reactivity were associated with durable graft-versus-leukemia effects. We analyzed 310 patients with acute leukemia who received allogeneic hematopoietic progenitor cell transplants from HLA-matched donors between 1982 and 2005 (229 with acute myelogenous leukemia, 81 with acute lymphoblastic leukemia). Mean post-transplant follow-up was 5 years (range, 0.5-22 years). Factors associated with relapse incidence, therapy for relapse, response to treatment, and post-relapse survival were assessed. One hundred of 310 patients (32%) with acute leukemia relapsed after transplantation, including 28 of 81 patients (35%) with acute lymphoblastic leukemia and 72 of 229 (31%) with acute myelogenous leukemia at a median of 136 days after transplantation. Median post-relapse survival periods were 51 days for the 69 patients who received chemotherapy/supportive care, 84 days for 11 recipients of donor lymphocyte infusions, 303 days for 13 recipients of second transplants, and 442 days for 7 patients treated with interferon-alpha and granulocyte-macrophage colony-stimulating factor. A multivariable Cox regression analysis indicated that a longer time to relapse after transplantation, peripheral blood as source of stem cells, and initial post-relapse therapy with cytokines, donor lymphocyte infusions, or second transplants were associated with improved post-relapse survival (P <.001, <.001, and .025). The outlook for patients with post-transplant relapse of acute leukemia is extremely poor; currently, no single therapy consistently results in durable remissions. Our study highlights the need for clinical trials in this area. Therapy with granulocyte-macrophage colony stimulating factor and interferon-alpha-2b is promising and will be pursued in a prospective trial at our center.