Predictors of outcomes of therapy-related acute myeloid leukemia after allogeneic hematopoietic stem cell transplantation

BACKGROUND/OBJECTIVE

Existing literature on allogeneic hematopoietic stem cell transplantation (allo-HSCT) in therapy-related acute myeloid leukemia (t-AML) is confounded by the inclusion of patients with secondary AML and t-MDS. We aim to report our 20-year experience of HSCT in t-AML.

METHODS

We retrospectively reviewed patients with t-AML who underwent HSCT. Patients were analyzed for prior malignancy, therapy, time to diagnosis of t-AML, transplant details, relapse-free survival (RFS), overall survival (OS), and predictors of outcomes.

RESULTS

In total, 68 patients (59.9% female; median age, 56.5 years) underwent HSCT. Acute and chronic graft-versus-host disease (GVHD) occurred in 39 (57.4%) and 23 (33.8%) patients, respectively. Cumulative incidence of relapse, nonrelapse mortality, RFS, and OS at 2 years were 17.9%, 34.5%, 47.6%, and 49.3%, respectively. Significant predictors of reduced OS were presence of 11q23 rearrangement (hazard ratio [HR], 3.24), using induction regimens other than FLAG-Ida or 7 + 3 (HR, 3.65), haploidentical donors (HR, 3.48), Eastern Cooperative Oncology Group performance status 2 or higher (HR, 5.83), and using cyclosporine A-methotrexate as GVHD prophylaxis (HR, 2.41). A significant decrement in survival was seen with an increasing number of any of these prognostic factors.

CONCLUSION

Outcomes of t-AML are satisfactory after allo-HSCT. Patients with t-AML with good-risk karyotypes, good performance status, having HLA-matched donors, and receiving intensive induction regimens have better outcomes after HSCT.

Safety of two-hour intermittent intravenous infusions of tacrolimus in the allogeneic hematopoietic stem cell transplantation unit

At our institution, tacrolimus is used as a second-line agent for the prevention and treatment of graft-versus-host-disease in the allogeneic hematopoietic stem cell transplantation (HSCT) unit after patients have experienced a serious or intolerable adverse event to cyclosporine. As per our standard practice, tacrolimus is administered via 2-h intermittent IV infusions (IIVs) every 12 h rather than continuous IV infusion. Shorter infusion times are cautioned due to concerns of higher rates of nephrotoxicity, neurotoxicity and infusion-related reactions, although there is a paucity of data to support this claim. Our primary objective was to evaluate the safety of a 2-h IIV of tacrolimus in an adult HSCT population. We retrospectively reviewed the charts of 104 patients who received tacrolimus by IIV (3574 doses; median = 22, range 1-158, IQR = 28) from 2002 to 2016. Primary outcomes collected include rates of nephrotoxicity, neurotoxicity and infusion-related reactions. One (0.9%) grade 2 infusion-related reaction occurred and resolved without discontinuation of tacrolimus. Of 16 incidences (13.6%) of nephrotoxicity, all but 10 (8.5%) cases resolved. Precipitating factors for nephrotoxicity unrelated to tacrolimus were identified in all 10 cases. There were 41 incidences (35%) of neurotoxicity, of which, 8 (6.8%) were considered serious. All neurotoxicity reverted to baseline or resolved completely. We propose that a 2-h IIV of tacrolimus is a safe method of administration in the adult HSCT setting.

Outcomes of therapy-related acute lymphoblastic leukemia in adults after allogeneic stem cell transplantation

INTRODUCTION

Therapy-related acute lymphoblastic leukemia (t-ALL) is an increasingly recognized subset of therapy-related acute leukemia. There are limited data on the role of allogeneic hematopoietic stem cell transplantation (HSCT) in t-ALL. Recent reports suggest comparable outcomes of t-ALL with de novo ALL after HSCT.

PATIENTS AND METHODS

We retrospectively reviewed all patients of t-ALL who underwent HSCT at our center. Patients were analyzed for prior malignancy, therapy, time to diagnosis of t-ALL, clinical, laboratory characteristics, transplant details, relapse-free survival (RFS), and overall survival (OS).

RESULTS

Eighteen patients (M:F ratio 1:1; Median age 44 years) underwent HSCT for t-ALL. Median latent period from primary malignancy to t-ALL was 44.8 months. 11q23 rearrangement and t(9;22) were present in 33.3% and 22.2% patients, respectively. Stem cell donors were matched related, matched unrelated, and haploidentical in 27.8% (n = 5), 55.6% (n = 10), and 16.7% (n = 3) patients, respectively. Five patients died before D+ 100 (27.8%). Estimated 2-year RFS and OS were 47.1% and 51.8%, respectively. We did not find any pretransplant and post-transplant risk factors that were predictive of improved OS or RFS after multivariate analysis.

CONCLUSIONS

Allogeneic HSCT outcomes in t-ALL were comparable to HSCT outcomes in de novo ALL. Multicenter studies with more patients and longer follow-up may provide factors affecting outcome and survival.

Reduced-intensity conditioning allogeneic transplant with dual T-cell depletion in myelofibrosis

BACKGROUND

There remains a significant mortality in recipients with MF who undergo allogeneic stem cell transplant (allo-HSCT). The combination of antithymocyte globulin (ATG) and post-transplant cyclophosphamide (PTCy) provides good control of graft-versus-host disease (GVHD) when peripheral blood stem cell grafts are used.

METHODS

We report the outcome of 37 recipients with myelofibrosis who underwent reduced-intensity conditioning (RIC) allo-HSCT with ATG and PTCy. Median follow-up was 16.4 months.

RESULTS

Nine (24.3%) recipients received 10/10 MRD grafts, 17 (45.9%) 10/10 MUD grafts, 4 (10.8%) 9/10 MUD grafts, and 7 (18.9%) haploidentical donor grafts. Six (16.3%) patients had graft failure. The cumulative incidence of grade II-IV and grade III-IV aGVHD at day +100 and moderate/severe chronic GVHD at 1 year was as follows: 13.5%, 5.4%, and 17%. There were no deaths secondary to GVHD. One-year overall survival (OS), relapse-free survival (RFS), non-relapse mortality (NRM), and GVHD-free/RFS (GRFS) were respectively 74.4%, 71.3%, 23%, and 43.3%. Those recipients who had worse KPS ≤ 80% had worse OS and RFS.

CONCLUSION

RIC allo-HSCT with ATG and PTCy results in high OS and RFS in patients with myelofibrosis and absence of mortality secondary to GVHD. Further investigations are required to reduce NRM and graft failure rates.

Reduced intensity allogeneic stem cell transplant with anti-thymocyte globulin and post-transplant cyclophosphamide in acute myeloid leukemia

OBJECTIVES

We aimed to study the efficacy of reduced intensity conditioning (RIC) allo-HSCT combined with anti-thymocyte globulin (ATG) and post-transplant cyclophosphamide (PTCy) for graft-versus-host disease (GVHD) prophylaxis in AML.

METHODS

One hundred forty-seven patients were included. All patients underwent unmanipulated peripheral blood stem cell RIC allo-HSCT. Median follow-up was 12.8 months (range 0.5-39).

RESULTS

Median age was 58 years. Twenty-nine (20%) recipients received 10/10 MRD grafts, 69 (47%) 10/10 MUD grafts, 20 (13.6%) 9/10 MMUD, and 29 (20%) haploidentical grafts. The cumulative incidence of grade II-IV and III-IV acute GVHD at day +100, and moderate/severe chronic GVHD at 1-year were as follow: 14.3%, 1.4%, and 8.3%. There were no significant differences according to donor type (P = .46) and cumulative incidence of GVHD. One-year overall survival (OS), relapse-free survival (RFS), non-relapse mortality, and GVHD-free/Relapse-free survival were as follows: 66.9% (95% CI 58.4-74), 59.9%, and 18.7% and 53.7%. KPS ≤ 80 was predictive of worst OS (P = .04). Those recipients who received MUD transplants had better RFS (P = .01).

CONCLUSIONS

RIC allo-HSCT combined with ATG and PTCy is safe and a potentially curative strategy and it is associated with impressive GRFS in AML.

Safety and Efficacy of Haploidentical Peripheral Blood Stem Cell Transplantation for Myeloid Malignancies Using Post-transplantation Cyclophosphamide and Anti-thymocyte Globulin as Graft-versus-Host Disease Prophylaxis

Haploidentical stem cell transplantation (haploSCT) has greatly improved access to curative treatment for myeloid malignancies in patients without suitable matched sibling/unrelated donors. We investigated the safety and efficacy of haploSCT after reduced intensity conditioning (RIC) with anti-thymocyte globulin (ATG), post-transplant cyclophosphamide (PTCy), and cyclosporine to prevent rejection and graft-versus-host disease (GVHD). In this study, 47 patients received RIC using fludarabine, busulfan, and total body irradiation (200 cGy). Unmanipulated peripheral blood grafts were used. GVHD prophylaxis included ATG (4.5 mg/kg day−3 to −1), PTCy (50 mg/kg/day day +3, +4), and cyclosporine from day +5. The median follow-up was 15 months (range 3–27). Thirty one (66%) patients had acute myeloid leukemia (AML), 10 (21%) had high-risk myelodysplastic syndrome, and 6 (13%) had a myeloproliferative neoplasia. Median age was 60 years (range 22–73). The d+100 cumulative incidences of grade II–IV and III–IV acute GVHD were 17% (95% confidence interval (CI) 7.9–29.1) and 6.4% (1.6–15.9), respectively. The cumulative incidence of moderate-severe chronic GVHD at 1 year was 15.2% (95% CI 6.5–27.1). Overall survival (OS) and relapse-free survival (RFS) were 55.2% (95% CI 39.5–68.4) and 49.5% (95% CI 34.2–63), respectively. Nonrelapse mortality (NRM) for all patients at 1 year was 37.1% (95% CI 23.2–51.1). Infection was the main cause of death (26%). For AML, 1-year OS, RFS, and NRM were 64.1% (95% CI 43.3–78.9), 54.5 (95% CI 34.6–70.7), and 26.8% (95% CI 12.3–43.6), respectively. In conclusion, unmanipulated haploidentical peripheral blood stem cells (PBSC) transplantation following RIC and dual in vivo T-cell depletion results in a low incidence of acute and chronic GVHD for patients diagnosed with myeloid malignancies.

Benefit of allogeneic transplantation in patients age ≥ 60 years with acute myeloid leukemia is limited to those in first complete remission at time of transplant

We evaluated the impact of age and remission status on 242 consecutive patients who underwent allogeneic hematopoietic cell transplantation for acute myeloid leukemia (AML) in our program between 1999 and 2011. Median age of all patients was 48 years (range, 18 to 71). Based on age and remission status, patients were divided into 4 groups: first complete remission (CR1) age <60 years (n = 116), second complete remission (CR2) age <60 years (n = 78), CR1 age ≥60 years (n = 32), and CR2 age ≥60 years (n = 16). Donors were matched related (n = 155, 64%) or matched unrelated (n = 87, 36%). Median follow-up of survivors was 65 months (range, 12 to 145). In a univariate analysis, 3-year overall survival rates of the 4 groups were 57%, 43%, 39%, and 16% (P = .003), respectively. In a multivariable analysis, hazard ratios of nonrelapse mortality and survival were 2.08 (P = .06) and 1.52 (P = .23), respectively, in patients ≥60 years in CR2 compared with ≥ 60 years in CR1. Although a plateau in survival was observed for patients ≥60 years in CR1 similar to those <60 years in CR1 and CR2, no long-term survivors were seen in patients ≥60 years in CR2. Our data suggest disappointing outcomes in AML patients ≥60 years of age transplanted in CR2. Therefore, if a transplant is indicated, early referral is recommended in patients ≥60 years with AML.

Similar Outcomes of Cryopreserved Allogeneic Peripheral Stem Cell Transplants (PBSCT) Compared to Fresh Allografts

The BMT program at Princess Margaret Hospital performed 105 transplants using cryopreserved peripheral blood stem cells (PBSC) from related allogeneic donors. The outcomes were compared with those of a historic control of 106 patients transplanted with freshly procured PBSC. The infusions were tolerated with limited toxicity related to nausea/vomiting or bradycardia, correlated with the total amount of DMSO infused. The average viability of the total nucleated cell (TNC) population after thawing was 71%. The survival of clonogenic progenitors amounted to 75% for colony-forming unit-granulocyte-macrophage (CFU-GM), 69% for burst-forming units erythroid (BFU-E), and 78% for colony-forming units granulocyte-erythrocyte-monocyte-megakaryocyte (CFU-GEMM). In contrast, colony-forming units megakaryocyte (CFU-MEG) was significantly more cryosensitive with recovery rates of 39%. The number of viable CD34(+) cells transplanted was correlated with the number of transplanted viable CFU-GM (P < .001), BFU-E (P < .001), CFU-MEG (P < .001), and CFU-GEMM (P = .049), but not with the TNC dose. The number of transplanted CD34(+) cells was correlated with engraftment of neutrophils (P = .012) and platelets (P = .013). The outcomes of cryopreseved or fresh PBSC transplants (PBSCT) with respect to engraftment of neutrophils (P = .178) and platelets (P = .785), lymphocyte recovery (P = .926), acute (P = .113), and chronic graft-versus-host disease (P = .673), recurrence (P = .295), nonrelapse mortality (P = .340), and overall survival (P = .668) were not significantly different. It is therefore reasonable to consider the option of cryopreserved allografts.

Long-term follow-up of allogeneic bone marrow transplantation for patients with chronic phase chronic myeloid leukemia prepared with a regimen consisting of cyclophosphamide, cytarabine and single-dose total body irradiation conditioning

We evaluated long-term toxicities and outcomes in 96 patients with chronic phase chronic myeloid leukemia treated with a single bone marrow allograft regimen. Conditioning was cytosine arabinoside, cyclophosphamide (120 mg/kg) and single fraction total body irradiation (500 cGy). Median follow-up was 12.8 years (0.4-19.9 years). Graft failure occurred in one patient, nonfatal veno-occlusive disease in 13 patients (14%). Overall incidences of acute (a) and chronic (c) graft-vs-host disease (GVHD) were 77 and 63%. The 100-day and 1-year transplant-related mortality (TRM) were 1 and 9.2%, respectively, with no change through 5 years. Five- and 10-year event-free survival rates were 56 and 49%, overall survival (OS) rates 72 and 70%, respectively. Forty patients have relapsed: 8 cytogenetic (20%), 10 hematologic (25%) and 22 molecular (55%). Most have been salvaged with donor-leukocyte infusion, second transplants and/or imatinib therapy. Survival was worse for patients transplanted >2 years from diagnosis (10-year OS 56 vs 78%, P=0.01), for patients over 50 years old (10-year OS 44 vs 75%, P=0.05) and for patients without cGVHD (10-year OS 53 vs 86%, P<0.001). This regimen resulted in successful engraftment, low risk of TRM and long-term survival. In an era when imatinib is first line therapy, this regimen offers a potentially low-toxicity, highly successful alternative in the event of poor imatinib response.

Autologous and allogeneic transplantation for multiple myeloma at a single centre

We report the results of a consecutive series of patients who underwent autologous (auto) (40), allogeneic (allo) (22) or syngeneic transplantation (2) for multiple myeloma (MM) at our centre. Median age at diagnosis was 45.5 (auto) and 43 (allo) years. Most patients had stage 2 (27% auto; 27% allo) or stage 3 (62% auto; 50% allo) disease and 73% demonstrated chemosensitivity prior to transplant. Median time from diagnosis to transplant was 18.6 months (auto) and 16.4 months (allo). Standard conditioning regimens were used. Median time to neutrophil engraftment was 11 days (7-18) (auto) and 18 days (13-24) (allo) and median time to platelet engraftment was 11 days (6-60) and 18 days (13-105), respectively. Ninety-day mortality was 5% (auto) and 27% (allo). Median follow-up was 15 months (6-48) (auto) and 42 months (24-52) (allo). Three-year progression-free survival (PFS) was 17 +/- 10% (auto) and 22 +/- 9% (allo) and 3-year overall survival (OS) was 74 +/- 11% (auto) and 32 +/- 10% (allo). Autologous transplantation for MM is a safe procedure with good OS although disease progression following transplant is frequent. Allogeneic transplantation has a high procedure-related mortality and PFS comparable to autologous transplantation but OS is poor. The early mortality and high OS of autologous transplantation in MM compares favourably with both the results of allogeneic transplantation and published results of standard therapy in this retrospective analysis.