Survival benefits from reduced-intensity conditioning in allogeneic stem cell transplantation for young lower-risk MDS patients without significant comorbidities

Objective: The aim of this study was to determine the optimum conditioning intensity for allogeneic stem cell transplantation (SCT) in young (age ≤50), lower‐risk (INT‐1 by IPSS) Myelodysplastic syndrome (MDS) patients without significant comorbidities (hematopoietic cell transplantation‐comorbidity index score ≤3). Methods: Transplant outcomes from 46 consecutive patients were retrospectively analyzed according to the conditioning intensity: reduced‐intensity conditioning (RIC; n = 14), intensified RIC by adding low‐dose total body irradiation (iRIC; n = 15), and myeloablative conditioning (MAC; n = 17). Results: After a median follow‐up of 73.7 months, RIC had a better 4‐yr overall survival (OS) (92.9%) compared with the iRIC (64.2%) or MAC (70.6%). Multivariate analysis showed that RIC was associated with improved OS compared with the MAC [relative risk (RR) of 0.08, P = 0.022] because of a lower transplant‐related mortality (TRM) (RR, 0.08, P = 0.035). iRIC failed to show survival benefits over the MAC (RR of 0.77, P = 0.689) because of similarly high TRM (RR of 0.41, P = 0.480). Cumulative incidence of acute and chronic graft‐versus‐host disease (GVHD) after RIC was higher, but GVHD‐specific survival was significantly better (RIC 100% vs. iRIC 45.7% vs. MAC, P = 0.018). Relapse rate was not different among the three groups, but in the RIC group, azacitidine was available and useful for inducing remission in two patients. Conclusion: This study shows that RIC improved OS by directly lowering TRM and indirectly giving an additional chance for relapsed MDS in the era of hypomethylating treatment. RIC–SCT should be considered for relative healthy lower‐risk MDS patients.     

Cyclophosphamide versus etoposide in combination with total body irradiation as conditioning regimen for adult patients with Ph‐negative acute lymphoblastic leukemia undergoing allogeneic stem cell transplant: On behalf of the ALWP of the European Society for Blood and Marrow Transplantation

Allogeneic hematopoietic cell transplantation (alloHCT) with myeloablative conditioning based on total body irradiation (TBI) is widely used for the treatment of adults with acute lymphoblastic leukemia (ALL). TBI is most frequently administered in combination with either cyclophosphamide (Cy/TBI) or etoposide (Vp/TBI). The goal of this study was to retrospectively compare these two regimens. Adult patients with Ph‐negative ALL treated with alloHCT in first or second complete remission who received Cy/TBI (n = 1346) or Vp/TBI (n = 152) conditioning were included in the analysis. In a univariate analysis, as compared to Cy/TBI, the use of Vp/TBI was associated with reduced incidence of relapse (17% vs. 30% at 5 years, P = .007), increased rate of leukemia‐free survival (60% vs. 50%, P = .04), and improved “graft versus host disease (GVHD) and relapse‐free survival” (GRFS, 43% vs. 33%, P = .04). No significant effect could be observed in terms of the incidence of nonrelapse mortality or acute or chronic GVHD. In a multivariate model, the use of Vp/TBI was associated with reduced risk of relapse (HR = 0.62, P = .04) while the effect on other study end‐points was not significant. In conclusion, conditioning regimen based on Vp combined with TBI appears more effective for disease control than the combination of Cy with TBI for adult patients with Ph‐negative ALL treated with alloHCT.     

Thiotepa‐based conditioning versus total body irradiation as myeloablative conditioning prior to allogeneic stem cell transplantation for acute lymphoblastic leukemia: A matched‐pair analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation

The optimal conditioning regimen to employ before hematopoietic stem cell transplantation in acute lymphoblastic leukemia (ALL) is still undecided, and while cyclophosphamide/total body irradiation (Cy/TBI) is the most commonly used myeloablative regimen, there are concerns regarding long‐term toxicity for patients conditioned with this regimen. Thiotepa‐based conditioning is an emerging radiation‐free regimen with recent publications indicative of comparable clinical outcomes to TBI‐based conditioning. In this analysis of the acute leukemia working party of the EBMT, we performed a retrospective matched‐pair analysis, evaluating the outcome of adult patients with ALL who received thiotepa‐based conditioning (n = 180) with those receiving Cy/TBI conditioning (n = 540). The 2‐year leukemia‐free survival and overall survival (OS) rates of both conditioning regimens were comparable, 33% for thiotepa [95% confidence interval (CI): 26.4‐42.8] versus 39% for Cy/TBI (95% CI: 34.8‐44.5] (P = .33) and 46.5% [95% CI: 38.6‐56.1] versus 48.8% [95% CI: 44.2‐54] (P = .9), respectively. There was no significant difference between the two regimens in the incidence of either acute graft versus host disease (GVHD) or chronic GVHD. Multivariate analysis demonstrated increased relapse incidence for thiotepa conditioning compared to Cy/TBI (HR = 1.78, 95% CI, 1.07‐2.95; P = .03) which did not affect OS. Our results indicate that thiotepa‐based conditioning may not be inferior to Cy/TBI for adult patients with ALL.     

Measurable residual disease,conditioning regimen intensity,and age predict outcome of allogeneic hematopoietic cell transplantation for acute myeloid leukemia in first remission: A registry analysis of 2292 patients by the Acute Leukemia Working Party European Society of Blood and Marrow Transplantation

Patients with acute myeloid leukemia (AML) in morphological first complete remission (CR1) pre‐allogeneic hematopoietic cell transplantation (HCT) may have measurable residual disease (MRD) by molecular and immunophenotyping criteria. We assessed interactions of MRD status with HCT conditioning regimen intensity in patients aged <50 years (y) or ≥50y. This was a retrospective study by the European Society for Blood and Marrow Transplantation registry. Patients were >18y with AML CR1 MRD NEG/POS and recipients of HCT in 2000‐2015. Conditioning regimens were myeloablative (MAC), reduced intensity (RIC) or non‐myeloablative (NMA). Outcomes included leukemia free survival (LFS), overall survival (OS), relapse incidence (RI), non‐relapse mortality (NRM), chronic graft‐vs‐host (cGVHD), and GVHD‐free and relapse‐free survival (GRFS). The 2292 eligible patients were categorized into four paired groups: <50y MRD POS MAC (N = 240) vs RIC/NMA (N = 58); <50y MRD NEG MAC (N = 665) vs RIC/NMA (N = 195); ≥50y MRD POS MAC (N = 126) vs RIC/NMA (N = 230), and ≥50y MRD NEG MAC (N = 223) vs RIC/NMA (N = 555). In multivariate analysis RIC/NMA was only inferior to MAC for patients in the <50y MRD POS group, with worse RI (HR 1.71) and LFS (HR 1.554). Patients <50Y MRD NEG had less cGVHD after RIC/NMA HCT (HR 0.714). GRFS was not significantly affected by conditioning intensity in any group. Patients aged <50y with AML CR1 MRD POS status should preferentially be offered MAC allo‐HCT. Prospective studies are needed to address whether patients with AML CR1 MRD NEG may be spared the toxicity of MAC regimens. New approaches are needed for ≥50y AML CR1 MRD POS.     

Haematopoietic stem cell transplantation for refractory Langerhans cell histiocytosis: outcome by intensity of conditioning

Patients with Langerhans cell histiocytosis (LCH) refractory to conventional chemotherapy have a poor outcome. There are currently two promising treatment strategies for high‐risk patients: the first involves the combination of 2‐chlorodeoxyadenosine and cytarabine; the other approach is allogeneic haematopoietic stem cell transplantation (HSCT). Here we evaluated 87 patients with high‐risk LCH who were transplanted between 1990 and 2013. Prior to the year 2000, most patients underwent HSCT following myeloablative conditioning (MAC): only 5 of 20 patients (25%) survived with a high rate (55%) of transplant‐related mortality (TRM). After the year 2000 an increasing number of patients underwent HSCT with reduced intensity conditioning (RIC): 49/67 (73%) patients survived, however, the improved survival was not overtly achieved by the introduction of RIC regimens with similar 3‐year probability of survival after MAC (77%) and RIC transplantation (71%). There was no significant difference in TRM by conditioning regimen intensity but relapse rates were higher after RIC compared to MAC regimens (28% vs. 8%, P = 0·02), although most patients relapsing after RIC transplantation could be salvaged with further chemotherapy. HSCT may be a curative approach in 3 out of 4 patients with high risk LCH refractory to chemotherapy: the optimal choice of HSCT conditioning remains uncertain.     

Increased risk of bacterial infection after engraftment in patients treated with allogeneic bone marrow transplantation following reduced‐intensity conditioning regimen

A. Shigematsu, S. Yamamoto, J. Sugita, T. Kondo, M. Onozawa, K. Kahata, T. Endo, S. Shiratori, S. Ota, K. Yamaguchi, K. Wakasa, M. Takahata, H. Goto, S. Ito, R. Takemura, J. Tanaka, S. Hashino, M. Nishio, T. Koike, M. Asaka, M. Imamura. Increased risk of bacterial infection after engraftment in patients treated with allogeneic bone marrow transplantation following reduced‐intensity conditioning regimen.
Transpl Infect Dis 2010: 12: 412–420. All rights reserved Abstract: Although bacterial infection is a major cause of death even after reduced‐intensity conditioning (RIC) for allogeneic stem cell transplantation (SCT), little is known about the epidemiology and risk factors. The incidence of bacterial infection in 43 patients who received allogeneic bone marrow transplantation (BMT) using a RIC regimen was compared with that in 68 patients who received BMT using a myeloablative conditioning regimen, and risk factors for bacterial infection were identified. Before engraftment, incidences of febrile neutropenia (FN) and documented infections (DI) were significantly decreased in RIC patients (FN: 59.5% vs. 89.6%, P<0.01, DI: 4.8% vs. 17.9%, P<0.01). However, incidence of bacterial infection was significantly increased in RIC patients in the post‐engraftment phase (53.8% vs. 11.1%, log‐rank, P<0.01). Blood stream was the most frequent focus of infection in both groups. In multivariate analysis, RIC and acute graft‐versus‐host disease were revealed to be significant risk factors for bacterial infection in this phase. In summary, risk of bacterial infection after engraftment was significantly higher in RIC patients, although infection was decreased before engraftment, and we need to develop a RIC‐specific strategy against bacterial infection after RIC SCT.     

Predictive value of risk assessment scores in patients with hematologic malignancies undergoing reduced‐intensity conditioning allogeneic stem cell transplantation

Reduced‐intensity conditioning allogeneic stem cell transplantation (RIC allo‐SCT) is associated with less toxicity and is used for older patients. We retrospectively studied the predictive value of two risk assessment scores, which were the hematopoietic cell transplantation‐specific comorbidity index (HCT‐CI) and the pre‐transplantation assessment of mortality (PAM) score, for assessing the outcome of RIC allo‐SCT. Seventy‐eight patients underwent transplantation between 2005 and 2013 at a single institution. RIC was performed with fludarabine and melphalan with/without total body irradiation. The 3‐year overall survival of patients with an HCT‐CI >3 was significantly worse than that of patients with an HCT‐CI 0–3 (31.6% vs. 59.6%, P = 0.020). Also, the 3‐year overall survival of patients with a PAM score >24 was significantly worse than that of those with a PAM score ≤24 (29.2% vs. 61.4%, P = 0.005). The present findings suggest that changing the cut‐off values of these risk assessment scores can improve prediction of outcomes in patients receiving RIC allo‐SCT with this conditioning regimen and we need validation by large‐scale study with other regimens. Am. J. Hematol. 89:E138–E141, 2014. © 2014 Wiley Periodicals, Inc.     

The addition of sirolimus to the graft‐versus‐host disease prophylaxis regimen in reduced intensity allogeneic stem cell transplantation for lymphoma: a multicentre randomized trial

Inhibition of the mechanistic target of rapamycin (mTOR) pathway has clinical activity in lymphoma. The mTOR inhibitor sirolimus has been used in the prevention and treatment of graft‐versus‐host disease (GVHD) after allogeneic haematopoietic stem cell transplantation (HSCT). A retrospective study suggested that patients with lymphoma undergoing reduced intensity conditioning (RIC) HSCT who received sirolimus as part of their GVHD prophylaxis regimen had a lower rate of relapse. We therefore performed a multicentre randomized trial comparing tacrolimus, sirolimus and methotrexate to standard regimens in adult patients undergoing RIC HSCT for lymphoma in order to assess the possible benefit of sirolimus on HSCT outcome. 139 patients were randomized. There was no difference overall in 2‐year overall survival, progression‐free survival, relapse, non‐relapse mortality or chronic GVHD. However, the sirolimus‐containing arm had a significantly lower incidence of grade II‐IV acute GVHD (9% vs. 25%, P = 0·015), which was more marked for unrelated donor grafts. In conclusion, the addition of sirolimus for GVHD prophylaxis in RIC HSCT is associated with no increased overall toxicity and a lower risk of acute GVHD, although it does not improve survival; this regimen is an acceptable option for GVHD prevention in RIC HSCT. This trial is registered at clinicaltrials.gov (NCT00928018).     

Reduced-intensity conditioning for myeloma: lower nonrelapse mortality but higher relapse rates compared with myeloablative conditioning

Despite the widespread adoption of reduced-intensity conditioning (RIC) for myeloma, there are few data comparing outcomes with RIC with myeloablative conditioning (MAC). We report the outcomes of patients undergoing allogeneic transplantations for myeloma and reported to the EBMT. A minimum data set was available on 320 RIC and 196 MAC allografts performed between 1998 and 2002. The RIC patients were older (51 vs 45 years) with more progressive disease (28% vs 21%) and more had received a prior transplant (76% vs 11%). In addition, there was a longer time to transplantation and an increased use of peripheral blood and T-cell depletion. For RIC and MAC, respectively, the nonrelapse mortality (NRM) at 2 years was 24% and 37% (P = .002); overall survival, 38.1% and 50.8% (not significant [ns]); and progression-free survival (PFS), 18.9% and 34.5% (P = .001). On multivariate analysis, RIC was associated with a reduction in NRM (HR, 0.5), but this was offset by an increase in relapse risk (HR, 2.0), and the conditioning intensity did not impact on overall survival or retain significance for PFS. These data suggest that there is a continuing need to investigate dose intensity in the conditioning for myeloma allografts.     

Diagnosis and evaluation of intestinal graft-versus-host disease after allogeneic hematopoietic stem cell transplantation following reduced-intensity and myeloablative conditioning regimens

Colonoscopic evaluation of mucosal tissues after allogeneic hematopoietic stem cell transplantation (HSCT) is very useful in evaluating pathogenesis and diagnosis of intestinal graft-versus-host disease (GVHD). However, information on the timing and sites of biopsies and the immunohistological evaluation of mucosal tissues for diagnosing intestinal GVHD, especially following reduced-intensity (RIC) regimens, remains very limited. A total of 33 patients with histologically proven GVHD after allogeneic HSCT with RIC (n = 23) and myeloablative conditioning (MAC, n = 10) regimens were enrolled in the present study. Colonoscopy was performed due to gastrointestinal symptoms, especially diarrhea and anorexia. Sites of biopsies with the worst histopathological grading were the terminal ileum in 67 % of patients. In the RIC group, the onset of diarrhea prior to colonoscopy examination was later (median: RIC, 57 vs. MAC, 27 days) and the number of patients who developed abdominal pain tended to be higher (RIC, 70 % vs. MAC, 30 %). A lower number of CD4+ cells and a higher ratio of Foxp3+ cells to CD4+ cells were detected in the involved lesions of intestinal GVHD following RIC. These differences in the RIC and MAC groups suggest that regimen-specific therapeutic strategies are required for diagnosing intestinal GVHD.     

Outcome of conditioning intensity in acute myeloid leukemia with monosomal karyotype in patients over 45 year‐old: A study from the acute leukemia working party (ALWP) of the European group of blood and marrow transplantation (EBMT)

Acute myeloid leukemia with monosomal karyotype (MK AML) carries a very poor prognosis, even after allogeneic stem cell transplantation (SCT). However, SCT remains the only curative option in this high‐risk population. Because myeloablative conditioning regimen (MAC) is associated with less relapse, we hypothesized that more intensive conditioning regimen might be beneficial for MK AML patients. We reviewed 303 patients over age 45 diagnosed with either de novo or secondary MK AML. One hundred and five patients received a MAC and 198 a reduced‐intensity conditioning (RIC). The median age at SCT was 57‐year‐old, significantly lower in the MAC (53‐year‐old) than in the RIC group (59‐year‐old). The median follow‐up was 42 months (range, 3 ? 156 months). The 3‐year overall survival (OS), leukemia‐free survival (LFS), and relapse rate (RR) were not significantly different between both groups with overall values of 34%, 29%, and 51%, respectively. On the contrary, the 3‐year nonrelapse mortality (NRM) was significantly higher in MAC recipients (28%) compared with RIC patients (16%, P = 0.004). The incidence of Grades II to IV acute graft‐versus‐host disease (GvHD) was significantly higher after a MAC (30.5%) than after a RIC (19.3%, P = 0.02). That of chronic GvHD was comparable between both groups (35%) and did not impact on LFS. Interestingly, within our MK AML cohort, hypodiploidy was significantly associated with worse outcomes. Due to reduced toxicity and comparable OS, LFS, and RR, RIC appears as a good transplant option in the very high‐risk population, including older patients, diagnosed with MK AML. Am. J. Hematol. 90:719–724, 2015. © 2015 Wiley Periodicals, Inc.     

Degree of mucositis and duration of neutropenia are the major risk factors for early post-transplant febrile neutropenia and severe bacterial infections after reduced-intensity conditioning

Background and objectives: Whether the intensity of the conditioning regimen affects febrile neutropenia (FN) and severe bacterial infections (SBIs) is not well established. We analyzed the risk factors (RFs) for the development of FN and SBI in the first 100 d post‐transplant in 195 consecutive adult recipients of a reduced‐intensity conditioning allogeneic hematopoietic stem cell transplantation (RIC‐allo). Materials and methods: The RIC regimens consisted of fludarabine plus melphalan (62%) or busulphan (38%) (FluMel or FluBu). SBIs include pneumonia, urinary tract infections, and bacteremia. Results: FN occurred in 141 patients (72%), always in the first 30 d post‐allo‐RIC. However, a SBI occurred in only 27 patients (14%) during this early post‐transplant period (P < 0.02) and NCI CTC grade III–IV mucosal damage in the first 10 d post‐transplantation (P = 0.03). RFs identified to SBI by multivariate analysis included corticosteroid therapy before day +100 (P < 0.01), mycophenolate mofetil‐based graft‐versus‐host disease (GVHD) prophylaxis (P < 0.01), and previous SBI before day +30 (P < 0.01). The rate of SBI from day +30 to +100 varied according to the number of RFs; thus, the rate of SBI was 1% in patients without any RF, 17% in patients with one RF, 29% with one RFs, and 53% in those with all three RFs. Conclusions: After an RIC‐allo, FN and early SBI occurred mostly in patients with severe mucositis and early‐onset neutropenia, while postengraftment high‐dose steroid therapy for acute GVHD was the major RF.     

Comparative outcomes of myeloablative and reduced-intensity conditioning allogeneic hematopoietic cell transplantation for therapy-related acute myeloid leukemia with prior solid tumor: A report from the acute leukemia working party of the European society for blood and bone marrow transplantation

Therapy-related acute myeloid leukemia (t-AML) arises as a late complication following antecedent solid tumors or hematologic diseases and their associated treatments. There are limited data regarding risk factors and outcomes following allogeneic hematopoietic cell transplantation (HCT) for t-AML following a prior solid tumor, and furthermore, the impact of myeloablative (MAC) vs reduced-intensity conditioning (RIC) on survival is unknown. The acute leukemia working party (ALWP) of the European society for blood and bone marrow transplantation (EBMT) performed a large registry study that included 535 patients with t-AML and prior solid tumor who underwent first MAC or RIC allogeneic HCT from 2000-2016. The primary endpoints of the study were OS and LFS. Patients receiving RIC regimens had an increase in relapse incidence (hazard ratio [HR], 1.52; 95% confidence interval [CI] 1.02-2.26; P = 0.04), lower LFS (HR, 1.52; 95% CI 1.12-2.05, P = 0.007), and OS (HR, 1.51; CI 1.09-2.09; P = 0.012 ) . There were no differences in NRM and GRFS. Importantly, LFS and OS were superior in patients receiving ablative regimens due to a decrease in relapse. As NRM continues to decline in the current era, it is conceivable that outcomes of HCT for t-AML with prior solid tumor may be improved by careful patient selection for myeloablative regimens.     

C-reactive protein levels before reduced-intensity conditioning predict outcome after allogeneic stem cell transplantation

The prognostic value of CRP levels before conditioning for allogeneic stem-cell transplantation (ASCT) was evaluated. Reduced-intensity conditioning (RIC) was given to 205 patients and conventional myeloablative conditioning (MAC) to 299 patients. Most patients had an HLA-compatible related or unrelated donor. There were 287 males and 216 females, median age 36 (1–69) years. Most patients received peripheral blood stem cells. Increased CRP levels (>10 mg/L) were detected in 129 patients (26%). Overall survival (OS) and transplant-related mortality (TRM) were worse for RIC patients with elevated CRP (67 vs. 43%, p = 0.005, and 16 vs. 30%, p = 0.036) while no difference was seen in MAC patients. An infection at the start of conditioning was seen in 27 RIC patients. We identified a subgroup of patients with an infection and elevated CRP (n = 16) and these patients had the worst outcome. In multivariate analysis, both infection and elevated CRP was the strongest factor associated with OS (HR 3.27, p < 0.001) and TRM (HR 4.35, p < 0.001). No correlation between any outcome variable and CRP was seen in MAC-treated patients. CRP may be a good prognostic factor for outcome after RIC and ASCT. It should be analyzed before conditioning, especially in patients with coexisting infection since patients with increased CRP and infection seem to have a very poor outcome after ASCT.     

Pre‐transplant cytomegalovirus (CMV) serostatus remains the most important determinant of CMV reactivation after allogeneic hematopoietic stem cell transplantation in the era of surveillance and preemptive therapy

B. George, N. Pati, N. Gilroy, M. Ratnamohan, G. Huang, I. Kerridge, M. Hertzberg, D. Gottlieb, K. Bradstock. Pre‐transplant cytomegalovirus (CMV) serostatus remains the most important determinant of CMV reactivation after allogeneic hematopoietic stem cell transplantation in the era of surveillance and preemptive therapy.
Transpl Infect Dis 2010: 12: 322–329. All rights reserved Abstract: Between January 2001 and June 2008, 315 adult patients (median age 43 years, range 16–65) including 203 males and 112 females undergoing hematopoietic stem cell transplantation (HSCT) had serial monitoring for cytomegalovirus (CMV) followed by initiation of preemptive therapy. The majority (62.1%) had a conventional myeloablative transplant with 116 (36.9%) having a reduced‐intensity conditioning (RIC) transplant, using either matched sibling/family (63.3%) or unrelated donors (36.7%). Graft source was peripheral blood stem cells in 257 (81.5%), bone marrow in 41 (13.1%), and cord blood in 16 (5.4%). T‐cell depletion with anti‐thymocyte globulin or alemtuzumab was used in 35%. Based upon CMV serostatus, patients were classified into low risk (donor [D]?/recipient [R]?), intermediate risk (D+/R?), or high risk (D?/R+ or D+/R+). Serial weekly monitoring for CMV viremia was performed using a qualitative polymerase chain reaction (PCR) and when positive, quantification was done using either pp65 antigen or a quantitative PCR. CMV reactivation was seen in 123 patients (39.1%) at a median of 50 days post HSCT (range 22–1978). CMV serostatus was the most important risk factor with incidence of 53% in the high‐risk group (53.3%) compared with 10.2% in the intermediate risk and 0% in the low‐risk group (P<0.0001). Other significant risk factors identified included use of alemtuzumab during conditioning (P=0.03), RIC transplants (P=0.06), and the presence of acute graft‐versus‐host disease (GVHD) (P<0.0001). On a multivariate analysis, CMV serostatus, RIC transplants, and acute GVHD remained independent predictors of CMV reactivation. All were treated with antiviral therapy with responses seen in 109 (88.6%). Sixteen patients (13%) developed CMV disease at a median of 59 days post HSCT (range 26 days–46 months), 8 of whom died. At a median follow up of 43 months (range 6–93), 166 patients (52.6%) are alive with a significantly higher survival among patients without CMV reactivation (57.2%) as compared with patients with CMV reactivation (45.5%; P=0.049). CMV reactivation and disease remains a major problem in high‐risk patients undergoing allogeneic HSCT. Novel prophylactic measures such as immunotherapy and drug prophylaxis need to be considered in this specific group of patients.     

Sequential chemotherapy followed by reduced‐intensity conditioning and allogeneic haematopoietic stem cell transplantation in adult patients with relapse or refractory acute myeloid leukaemia: a survey from the Acute Leukaemia Working Party of EBMT

This study analysed the outcome of 267 patients with relapse/refractory acute myeloid leukaemia (AML ) who received sequential chemotherapy including fludarabine, cytarabine and amsacrine followed by reduced‐intensity conditioning (RIC ) and allogeneic haematopoietic stem cell transplantation (HSCT ). The transplants in 77 patients were from matched sibling donors (MSD s) and those in 190 patients were from matched unrelated donors. Most patients (94·3%) were given anti‐T‐cell antibodies. The incidence of acute graft‐versus‐host disease (GVHD ) of grades II ‒IV was 32·1% and that of chronic GVHD was 30·2%. The 3‐year probability of non‐relapse mortality (NRM ) was 25·9%, that of relapse was 48·5%, that of GVHD ‐free and relapse‐free survival (GRFS ) was 17·8% and that of leukaemia‐free survival (LFS ) was 25·6%. In multivariate analysis, unrelated donor recipients more frequently had acute GVHD of grades II ‒IV [hazard ratio (HR ) = 1·98, P  = 0·017] and suffered less relapses (HR  = 0·62, P  = 0·01) than MSD recipients. Treatment with anti‐T‐cell antibodies reduced NRM (HR  = 0·35, P  = 0·01) and improved survival (HR  = 0·49, P  = 0·01), GRFS (HR  = 0·37, P  = 0·0004) and LFS (HR  = 0·46, P  = 0·005). Thus, sequential chemotherapy followed by RIC HSCT and use of anti‐T‐cell antibodies seems promising in patients with refractory AML .     

Treatment with mesenchymal stromal cells is a risk factor for pneumonia-related death after allogeneic hematopoietic stem cell transplantation

We performed a retrospective cohort study to find out whether the use of reduced‐intensity conditioning (RIC) might reduce the risk of early death from pneumonia. Pneumonia‐associated deaths were evaluated in 691 hematopoietic stem cell transplantation (HSCT) patients. The majority had a hematological malignancy (n = 504) and an HLA‐matched donor (n = 584). RIC was given to 336 patients and myeloablative conditioning (MAC) to 355. Data concerning radiology, culture and autopsy results were evaluated together with risk factors for death related to pneumonia within or after 100 d after HSCT (early and overall pneumonia). In 60 patients, pneumonia contributed to death (early n = 17). The cumulative incidence of early pneumonia‐related death was 2.8% and 2.1% in MAC and RIC patients, respectively. The cumulative incidence of overall pneumonia‐related death was 8.2% and 10.5%, respectively. In 40 patients, (67%) an etiology could be established, with 19 patients having proven or probable mold infection. In the multivariate analyses, acute graft‐versus‐host disease (GVHD) grades II–IV, cytomegalovirus (CMV) infection and having received mesenchymal stromal cells (MSCs) were factors associated with overall pneumonia‐related death. Bacteremia and a previous HSCT were associated with early pneumonia‐related death. RIC did not reduce the incidence of early death associated with pneumonia. Acute GVHD II–IV, CMV infection and MSC treatment were factors associated with pneumonia‐related death. Mold infection was the most common contributor to pneumonia‐related death in HSCT patients.     

GVHD prophylaxis using low‐dose cyclosporine improves survival in leukaemic recipients of HLA‐identical sibling transplants

Graft‐versus‐host disease (GVHD) prophylaxis of short duration (6 months) with low‐dose cyclosporine A (CsA) starting at 1 mg/kg per day i.v. and four doses of methotrexate (MTX) were given to 171 consecutive leukaemic recipients of HLA‐identical sibling transplants. In contrast, apart from MTX, retrospective controls received high‐dose CsA, starting at 5–7.5 mg/kg per day i.v. and discontinued 1 yr post‐transplant. In the low‐dose CsA group, the probability of acute GVHD grades I–II (70% vs. 53%, P < 0.01), and chronic GVHD were increased (58% vs. 25%, P < 0.01), whereas the incidences of acute GVHD grades III–IV (9% vs. 5%, P = 0.62), and non‐relapse mortality (20% vs. 22%, P = 0.58) were similar. Moreover, the probability of relapse was decreased (31% vs. 54%, P < 0.01), and both relapse‐free (56% vs. 38%, P = 0.04) and overall survival (61% vs. 40%, P = 0.04) were markedly improved using the low‐dose CsA regimen. In multivariate analyses, low‐dose CsA was strongly associated with chronic GVHD [relative hazard (RH) 2.56, P < 0.01], which decreased the risk of relapse (RH 0.46, P < 0.01) and improved the probability of survival (RH 1.84, P < 0.01). In conclusion, a low‐dose CsA regimen in leukaemic recipients of HLA‐identical sibling transplants increases the rate of chronic GVHD, which seems to attenuate the risk of relapse, thereby improving patient survival owing to enhanced graft‐versus‐leukaemia effect.     

Post‐transplantation cyclophosphamide versus conventional graft‐versus‐host disease prophylaxis in mismatched unrelated donor haematopoietic cell transplantation

Post‐transplantation cyclophosphamide (PTCy) is an effective strategy to prevent graft‐versus‐host disease (GVHD) after haploidentical haematopoietic cell transplantation (HCT). We determined the efficacy of PTCy‐based GVHD prophylaxis in human leucocyte antigen (HLA)‐mismatched unrelated donor (MMUD) HCT. We analysed 113 adult patients with high‐risk haematological malignancies who underwent one‐antigen MMUD transplantation between 2009 and 2013. Of these, 41 patients received PTCy, tacrolimus and mycophenolate mofetil (MMF) for GVHD prophylaxis; 72 patients received conventional prophylaxis with anti‐thymocyte globulin, tacrolimus and methotrexate. Graft source was primarily bone marrow (83% PTCy vs. 63% conventional group). Incidence of grade II–IV (37% vs. 36%, P = 0·8) and grade III–IV (17% vs. 12%, P = 0·5) acute GVHD was similar at day 100. However, the incidence of grade II‐IV acute GVHD by day 30 was significantly lower in the PTCy group (0% vs. 15%, P = 0·01). Median time to neutrophil (18 days vs. 12 days, P < 0·001) and platelet (25·5 days vs. 18 days, P = 0·05) engraftment was prolonged in PTCy group. Rates of graft failure, chronic GVHD, 2‐year non‐relapse mortality, relapse, progression‐free survival or overall survival were similar. Our results demonstrate that PTCy, tacrolimus and MMF for GVHD prophylaxis is safe and produced similar results as conventional prophylaxis in patients with one antigen HLA‐MMUD HCT.     

Reduced intensity conditioned allograft yields favorable survival for older adults with B‐cell acute lymphoblastic leukemia

Older adults with B‐cell acute lymphoblastic leukemia (B‐ALL) have poor survival. We examined the effectiveness of reduced intensity conditioning (RIC) hematopoietic cell transplant (HCT) in adults with B‐ALL age 55 years and older and explored prognostic factors associated with long‐term outcomes. Using CIBMTR registry data, we evaluated 273 patients (median age 61, range 55–72) with B‐ALL with disease status in CR1 (71%), >CR2 (17%) and Primary Induction Failure (PIF)/Relapse (11%), who underwent RIC HCT between 2001 and 2012 using mostly unrelated donor (59%) or HLA‐matched sibling (32%). Among patients with available cytogenetic data, the Philadelphia chromosome (Ph+) was present in 50%. The 3‐year cumulative incidences of nonrelapse mortality (NRM) and relapse were 25% (95% confidence intervals (CI): 20–31%) and 47% (95% CI: 41–53%), respectively. Three‐year overall survival (OS) was 38% (95% CI: 33–44%). Relapse remained the leading cause of death accounting for 49% of all deaths. In univariate analysis, 3 year risk of NRM was significantly higher with reduced Karnofsky performance status (KPS <90: 34% (95% CI: 25–43%) versus KPS ≥90 (18%; 95% CI: 12–24%, P = 0.006). Mortality was increased in older adults (66+ vs. 55–60: Relative Risk [RR] 1.51 95% CI: 1.00–2.29, P = 0.05) and those with advanced disease (RR 2.13; 95% CI: 1.36–3.34, P = 0.001). Survival of patients in CR1 yields 45% (95% CI: 38–52%) at 3 years and no relapse occurred after 2 years. We report promising OS and acceptable NRM using RIC HCT in older patients with B‐ALL. Disease status in CR1 and good performance status are associated with improved outcomes. Am. J. Hematol. 92:42–49, 2017. © 2016 Wiley Periodicals, Inc.