Isocitrate dehydrogenase (IDH) 1 and 2 mutations predict better outcome in patients with acute myeloid leukemia undergoing allogeneic hematopoietic cell transplantation: a study of the ALWP of the EBMT.

Isocitrate dehydrogenase 1 and 2 (IDH1 and IDH2) mutations have uncertain prognostic implications in AML. We investigate the impact IDH1 and IDH2 mutations in AML patients undergoing allogeneic hematopoietic cell transplantation (allo-HCT) in first complete remission (CR1). In total, 1515 adult patients were included, 15.91% (n = 241) carried IDH1 mutation (mIDH1), and 26.27% (n = 398) IDH2 mutation (mIDH2) and 57.82% (n = 876) had no-IDH mutation. NPM1 was frequently encountered with IDH1 mutation (no-IDH group, n = 217, 24.8%, mIDH1, n = 103, 42.7%, mIDH2, n = 111, 27.9%, p < 0.0001). At day 180, the cumulative incidence (CI) of grade II-IV acute graft-versus-host disease (GVHD) was significantly lower in mIDH1 and mIDH2 compared to no-IDH groups (Hazard ratio [HR] = 0.66 (95% CI 0.47-0.91), p = 0.011; HR = 0.73 (95% CI 0.56-0.96), p = 0.025, respectively). In the mIDH1 group, overall survival (OS) was improved compared to no-IDH (HR = 0.68 (95% CI 0.48-0.94), p = 0.021), whereas mIDH2 was associated with lower incidence of relapse (HR = 0.49 (95% CI 0.34-0.7), p < 0.001), improved leukemia free survival (LFS) (HR = 0.7 (95% CI 0.55-0.9), p = 0.004) and OS (HR = 0.74 (95% CI 0.56-0.97), p = 0.027). In the subgroup of NPM1 wild type, only IDH2 was associated with improved outcomes. In conclusion, our data suggest that IDH1 and IDH2 mutations are associated with improved outcomes in patients with AML undergoing allo-HCT in CR1.

Externally Controlled Studies Using Real-World Data in Patients With Hematological Cancers: A Systematic Review.

Importance: The use of real-world data (RWD) external control arms in prospective studies is increasing. The advantages, including the immediate availability of a control population, must be balanced with the requirements of meeting evidentiary standards. Objective: To address the question of whether and to what extent the methods of RWD studies compare to standard methods used in randomized clinical trials. Evidence Review: A systematic search across 4 electronic databases and Google Scholar was conducted from January 1, 2000, to October 23, 2023. Studies were included in the systematic review if they compared an intervention arm in a clinical trial to an RWD control arm in patients with hematological cancers and if they were published between 2000 and 2023. Findings: Thirty-two prospective intervention studies incorporating external control data from RWD sources of patients with hematological cancers were identified. A total of 4306 patients from intervention arms and 10 594 from RWD control arms were included across all studies. Only 2 studies (6%) included prospectively collected RWD. The complete trial inclusion criteria were applied to the RWD cohort in 7 studies (22%). Four studies (13%) published the statistical analysis plan and prespecified use of RWD. A total of 23 studies (72%) applied matching algorithms for trial and RWD cohorts, including matching for demographic, disease, and/or therapy-related characteristics. The end point criteria were the same as the trial in 8 studies (25%). In contrast, 12 studies (38%) used different end points, and 12 (38%) did not provide an end point definition for the RWD. Twelve studies (38%) had a median follow-up difference of less than a year between arms. Eight studies (25%) reported toxic effect data for the trial arm, of which 5 studies reported toxic effect data for the RWD arm. Conclusions and Relevance: In this systematic review, limitations were observed in the application of clinical trial eligibility criteria to RWD, statistical rigor and application of matching methods, the definition of end points, follow-up, and reporting of adverse events, which may challenge the conclusions reported in studies using RWD.

Prediction of sustained remission after tyrosine kinase inhibitor discontinuation with BCR::ABL1 digital PCR in chronic myeloid leukemia patients.

Precise and reliable predictive parameters to accurately identify chronic myeloid leukemia (CML) patients who can successfully discontinue their tyrosine kinase inhibitor (TKI) treatment are lacking. One promising parameter is depth of molecular response measured by BCR::ABL1 digital PCR (dPCR). The aim of this study was to validate a previously described prediction cutoff of 0.0023%IS and to assess the value of dPCR for treatment-free remission (TFR) prediction in relation to other clinical parameters. A droplet-based dPCR assay assessed BCR::ABL1 %IS prior to TKI discontinuation. The primary endpoint was molecular recurrence (MolR) by 36 months. A total of 186 patients from Canada, Germany, and the Netherlands were included. In patients with a first TKI discontinuation attempt (n = 163), a BCR::ABL1 dPCR < and ≥0.0023%IS had a MolR probability of 33% and 70%, respectively. Patients treated less than 6 years with a BCR::ABL1 dPCR <0.0023%IS had a MolR probability of 31%. After correction for treatment duration, both high dPCR value and the use of imatinib (vs. second-generation TKI) were significantly associated with a higher risk of MolR (HR of 3.66, 95%CI 2.06-6.51, p < .001; and 2.85, 95%CI 1.25-6.46, p = .013, respectively). BCR::ABL1 dPCR was not associated with TFR outcome after second TKI discontinuation, however, with the limitation of a small number of patients analyzed (n = 23). In conclusion, BCR::ABL1 digital PCR based on the cutoff of 0.0023%IS is a valuable predictive tool to identify CML patients with a high probability of TFR success after first TKI discontinuation, including patients treated for less than 6 years.

Impact of the Type of Tyrosine Kinase Inhibitor (imatinib or dasatinib) Used Before allo-HCT on Outcome of Patients with Philadelphia-Positive Acute Lymphoblastic Leukemia. A Study on Behalf of the Acute Leukemia Working Party of the EBMT.

The use of tyrosine kinase inhibitors (TKIs) during induction and consolidation, followed by allogeneic hematopoietic cell transplantation (allo-HCT), is a standard of care for patients with Philadelphia (Ph)-positive acute lymphoblastic leukemia (ALL). The goal of this study was to compare results of allo-HCT according to the type of TKI used pre-transplant, either imatinib, dasatinib or both. This was a retrospective, registry-based analysis including adult patients with Ph-positive ALL treated with allo-HCT between years 2010-2022. The analysis included 606 patients pre-treated with imatinib, 163 with dasatinib and 94 with both imatinib and dasatinib. Allo-HCTs were performed in first complete remission from either unrelated (56%), matched sibling (36%) or haploidentical donors (8%). Relapse incidence at 2 years was 26% in the imatinib group and 21% in the dasatinib group and 19% in the imatinib + dasatinib group (P = .06) while non-relapse mortality was 19%, 15%, and 23%, respectively (P = .37). No significant differences were found for leukemia-free survival (55% vs. 63% vs. 58%, P = .11) and overall survival (72% vs. 76% vs. 65%, P = .32). The incidence of grade 2-4 acute graft-versus-host disease (GVHD) and chronic GVHD was comparable across study groups, while the incidence of grade 3-4 acute GVHD was significantly increased for patients pre-treated with dasatinib alone (20%) than in the imatinib group (10%) or imatinib + dasatinib group (13%) (P = .002). On multivariate analysis a chance of GVHD and relapse-free survival (GRFS) was significantly decreased while the risk of grade 3-4 acute GVHD was increased for the dasatinib compared to imatinib group (hazard ratio, HR = 1.27, P = .048 and HR = 2.26, P = .0009, respectively). This study provides no evidence for the advantage of one TKI over another in terms of LFS and OS. However, the use of dasatinib is associated with increased risk of severe acute GVHD and decreased GRFS.

Does IPSS-R downstaging before transplantation improve the prognosis of patients with myelodysplastic neoplasms?

ABSTRACT: In patients with myelodysplastic syndrome (MDS), higher revised International Prognostic Scoring System (IPSS-R) scores at transplant are associated with worse transplant outcome and, thus, lowering IPSS-R scores by therapeutic intervention before transplantation may seem beneficial. However, there is no evidence, to date, to support this approach. In a retrospective analysis, a total of 1482 patients with MDS with sufficient data to calculate IPSS-R score at diagnosis and at time of transplantation were selected from the European Society for Blood and Marrow Transplantation transplant registry and analyzed for transplant outcome in a multivariable Cox model including IPSS-R score at diagnosis, treatment intervention, change in IPSS-R score before transplant, and several patient and transplant variables. Transplant outcome was unaffected by IPSS-R score change in untreated patients and moderately superior in patients treated with chemotherapy with improved IPSS-R score at transplant. Improved IPSS-R score after hypomethylating agents (HMAs) or other therapies showed no beneficial effect. However, when IPSS-R score progressed after chemotherapy, HMAs, or other therapies, transplant outcome was worse than without any prior treatment. Similar results were found when reduction or increase in bone marrow (BM) blasts between diagnosis and transplantation was considered. The results show a limited benefit of IPSS-R score downstaging or reduction of BM blasts after chemotherapy and no benefit for HMAs or other treatments and thus question the role of prior therapy in patients with MDS scheduled for transplantation. The model-based survival estimates should help inform decision-making for both doctors and patients.

Benefits and risks of clofarabine in adult acute lymphoblastic leukemia investigated in depth by multi-state modeling.

BACKGROUND: We recently reported results of the prospective, open-label HOVON-100 trial in 334 adult patients with acute lymphoblastic leukemia (ALL) randomized to first-line treatment with or without clofarabine (CLO). No improvement of event-free survival (EFS) was observed, while a higher proportion of patients receiving CLO obtained minimal residual disease (MRD) negativity. AIM: In order to investigate the effects of CLO in more depth, two multi-state models were developed to identify why CLO did not show a long-term survival benefit despite more MRD-negativity. METHODS: The first model evaluated the effect of CLO on going off-protocol (not due to refractory disease/relapse, completion or death) as a proxy of severe treatment-related toxicity, while the second model evaluated the effect of CLO on obtaining MRD negativity. The subsequent impact of these intermediate events on death or relapsed/refractory disease was assessed in both models. RESULTS: Overall, patients receiving CLO went off-protocol more frequently than control patients (35/168 [21%] vs. 18/166 [11%], p = 0.019; HR 2.00 [1.13-3.52], p = 0.02), especially during maintenance (13/44 [30%] vs. 6/56 [11%]; HR 2.85 [95%CI 1.08-7.50], p = 0.035). Going off-protocol was, however, not associated with more relapse or death. Patients in the CLO arm showed a trend towards an increased rate of MRD-negativity compared with control patients (HR MRD-negativity: 1.35 [0.95-1.91], p = 0.10), which did not translate into a significant survival benefit. CONCLUSION: We conclude that the intermediate states, i.e., going off-protocol and MRD-negativity, were affected by adding CLO, but these transitions were not associated with subsequent survival estimates, suggesting relatively modest antileukemic activity in ALL.

Bayesian interim analysis for prospective randomized studies: reanalysis of the acute myeloid leukemia HOVON 132 clinical trial.

Randomized controlled trials (RCTs) are the gold standard to establish the benefit-risk ratio of novel drugs. However, the evaluation of mature results often takes many years. We hypothesized that the addition of Bayesian inference methods at interim analysis time points might accelerate and enforce the knowledge that such trials may generate. In order to test that hypothesis, we retrospectively applied a Bayesian approach to the HOVON 132 trial, in which 800 newly diagnosed AML patients aged 18 to 65 years were randomly assigned to a "7 + 3" induction with or without lenalidomide. Five years after the first patient was recruited, the trial was negative for its primary endpoint with no difference in event-free survival (EFS) between experimental and control groups (hazard ratio [HR] 0.99, p = 0.96) in the final conventional analysis. We retrospectively simulated interim analyses after the inclusion of 150, 300, 450, and 600 patients using a Bayesian methodology to detect early lack of efficacy signals. The HR for EFS comparing the lenalidomide arm with the control treatment arm was 1.21 (95% CI 0.81-1.69), 1.05 (95% CI 0.86-1.30), 1.00 (95% CI 0.84-1.19), and 1.02 (95% CI 0.87-1.19) at interim analysis 1, 2, 3 and 4, respectively. Complete remission rates were lower in the lenalidomide arm, and early deaths more frequent. A Bayesian approach identified that the probability of a clinically relevant benefit for EFS (HR < 0.76, as assumed in the statistical analysis plan) was very low at the first interim analysis (1.2%, 0.6%, 0.4%, and 0.1%, respectively). Similar observations were made for low probabilities of any benefit regarding CR. Therefore, Bayesian analysis significantly adds to conventional methods applied for interim analysis and may thereby accelerate the performance and completion of phase III trials.

Attitudes of healthcare professionals and drug regulators about progression-free survival as endpoint in the advanced cancer setting.

PURPOSE: To describe the attitudes of healthcare professionals and drug regulators about progression-free survival (PFS) as efficacy endpoint in clinical trials with patients with advanced cancer and to explore to what extent these attitudes influence the willingness to trade between PFS and toxicity. METHODS: Cross-sectional survey with regulators from the European Medicines Agency (EMA), and healthcare professionals (HCP) from the "Stichting Hemato-Oncologie voor Volwassenen Nederland" (HOVON) collaborative group and the European Organisation for Research and Treatment of Cancer (EORTC). Attitudes towards PFS were elicited using 5-point Likert items. The respondents' willingness to trade between PFS and grade 3 or 4 (G34) toxicity was assessed using the threshold technique and quantified in terms of their maximum acceptable risk (MAR). RESULTS: Responses were collected from 287 HCPs and 64 regulators with mainly clinical expertise. Attitudes towards PFS were often spread out in both groups and related to beliefs about PFS being a likely surrogate for clinical benefit, being an intrinsic benefit to be distinguished from OS, or on the importance given to OS. Being a regulator or holding stronger beliefs about PFS being a likely surrogate or an intrinsic benefit were associated with a higher MAR. Presence of a supportive trend in OS was stated as important but was not associated with MAR. There was agreement on the need to address bias in the adjudication of PFS and the need for improving communication to patients about meaning, strengths, and limitations of improvements in PFS. CONCLUSION: Attitudes towards PFS were spread out and were associated with individual differences in the willingness to trade between toxicity and PFS. There was agreement on the need to address bias in the adjudication of PFS and improving communication to patients.

BCR::ABL1 kinase domain mutation testing and clinical outcome in a nationwide chronic myeloid leukemia patient population.

OBJECTIVES: Acquired missense mutations in the BCR::ABL1 kinase domain (KD) may cause tyrosine kinase inhibitor (TKI) treatment failure. Based on mutation-specific in vitro derived IC50-values, alternative TKI may be selected. We assessed clinical practice of BCR::ABL1 KD mutation testing, clinical response in relation to IC50-values, and clinical outcome of tested patients. METHODS: Patients from six Dutch CML reference centers and a national registry were included once a mutational analysis was performed. Reasons for testing were categorized as suboptimal TKI response, and primary or secondary TKI resistance. RESULTS: Four hundred twenty analyses were performed in 275 patients. Sixty-nine patients harbored at least one mutation. Most analyses were performed because of suboptimal TKI response but with low mutation incidence (4%), while most mutations were found in primary and secondary resistant patients (21% and 51%, respectively). Harboring a BCR::ABL1 mutation was associated with inferior overall survival (HR 3.2 [95% CI, 1.7-6.1; p < .001]). Clinically observed responses to TKI usually corresponded with the predicted TKI sensitivity based on the IC50-values, but a high IC50-value did not preclude a good clinical response per se. CONCLUSIONS: We recommend BCR::ABL1 KD mutation testing in particular in the context of primary or secondary resistance. IC50-values can direct the TKI choice for CML patients, but clinical efficacy can be seen despite adverse in vitro resistance.

Inhibitory NKG2A+ and absent activating NKG2C+ NK cell responses are associated with the development of EBV+ lymphomas.

Epstein-Barr virus (EBV) is a ubiquitous herpesvirus, which infects over 90% of the adult human population worldwide. After primary infections, EBV is recurrently reactivating in most adult individuals. It is, however, unclear, why these EBV reactivations progress to EBV+ Hodgkin (EBV+HL) or non-Hodgkin lymphomas (EBV+nHL) only in a minority of EBV-infected individuals. The EBV LMP-1 protein encodes for a highly polymorphic peptide, which upregulates the immunomodulatory HLA-E in EBV-infected cells, thereby stimulating the inhibitory NKG2A-, but also the activating NKG2C-receptor on natural killer (NK) cells. Using a genetic-association approach and functional NK cell analyses, we now investigated, whether these HLA-E-restricted immune responses impact the development of EBV+HL and EBV+nHL. Therefore, we recruited a study cohort of 63 EBV+HL and EBV+nHL patients and 192 controls with confirmed EBV reactivations, but without lymphomas. Here, we demonstrate that in EBV+ lymphoma patients exclusively the high-affine LMP-1 GGDPHLPTL peptide variant-encoding EBV-strains reactivate. In EBV+HL and EBV+nHL patients, the high-expressing HLA-E*0103/0103 genetic variant was significantly overrepresented. Combined, the LMP-1 GGDPHLPTL and HLA-E*0103/0103 variants efficiently inhibited NKG2A+ NK cells, thereby facilitating the in vitro spread of EBV-infected tumor cells. In addition, EBV+HL and EBV+nHL patients, showed impaired pro-inflammatory NKG2C+ NK cell responses, which accelerated the in vitro EBV-infected tumor cells spread. In contrast, the blocking of NKG2A by monoclonal antibodies (Monalizumab) resulted in efficient control of EBV-infected tumor cell growth, especially by NKG2A+NKG2C+ NK cells. Thus, the HLA-E/LMP-1/NKG2A pathway and individual NKG2C+ NK cell responses are associated with the progression toward EBV+ lymphomas.

Allogeneic Stem Cell Transplantation in Patients >40 Years of Age With Acute Lymphoblastic Leukemia: Reduced Intensity Versus Myeloablative Conditioning.

BACKGROUND: The outcome in older patients with acute lymphoblastic leukemia (ALL) remains unsatisfactory due to high relapse and nonrelapse mortality (NRM) rates. Allogeneic stem cell transplantation (alloHSCT) as postremission therapy has an important role in reducing relapse rate, albeit its application is limited in older adult patients due to alloHSCT-related morbidity and mortality. Reduced-intensity conditioning (RIC) alloHSCT has been developed as a less toxic conditioning regimen, but comparative studies with myeloablative conditioning (MAC) are limited in patients with ALL. METHODS: In this retrospective study, RIC-alloHSCT (n = 111) was compared with MAC-alloHSCT (n = 77) in patients aged 41 to 65 y with ALL in first complete remission. MAC was predominantly applied by combining high-dose total body irradiation and cyclophosphamide, whereas RIC mainly consisted of fludarabine and 2 Gy total body irradiation. RESULTS: Unadjusted overall survival was 54% (95% confidence interval [CI], 42%-65%) at 5 y in MAC recipients compared with 39% (95% CI, 29%-49%) in RIC recipients. Overall survival and relapse-free survival were not significantly associated with type of conditioning after adjusted for the covariates age, leukemia risk status at diagnosis, donor type, and donor and recipient gender combination. NRM was significantly lower after RIC (subdistribution hazard ratio: 0.41, 95% CI, 0.22-0.78; P = 0.006), whereas relapse was significantly higher (subdistribution hazard ratio: 3.04, 95% CI, 1.71-5.40; P < 0.001). CONCLUSIONS: Collectively, RIC-alloHSCT has resulted in less NRM, but it was also found to be associated with a significantly higher relapse rate. These results suggest that MAC-alloHSCT may provide a more effective type of consolidation therapy for the reduction of relapse and that RIC-alloHSCT may be restricted to patients at higher risk for NRM.

Matched related versus unrelated versus haploidentical donors for allogeneic transplantation in AML patients achieving first complete remission after two induction courses: a study from the ALWP/EBMT.

We compared transplants (HSCT) from matched related siblings (MSD) with those from matched 10/10 and mismatched 9/10 unrelated (UD) and T-replete haploidentical (Haplo) donors in acute myeloid leukemia (AML) in first complete remission (CR1) achieved after two inductions, a known poor prognostic factor. One thousand two hundred and ninety-five patients were included: MSD (n = 428), UD 10/10 (n = 554), UD 9/10 (n = 135), and Haplo (n = 178). Acute GVHD II-IV was higher in all groups compared to MSD. Extensive chronic (c) GVHD was significantly higher in UD 9/10 (HR = 2.52; 95% CI 1.55-4.11, p = 0.0002) and UD 10/10 (HR = 1.48; 95% CI 1.03-2.13, p = 0.036) and cGVHD all grades were higher in UD 9/10 vs MSD (HR = 1.77; 95% CI 1.26-2.49, p = 0.0009). Non-relapse mortality was higher in all groups compared to MSD. Relapse incidence, leukemia-free, and overall survival did not differ significantly between donor types. Finally, GVHD-free relapse-free survival was lower in HSCT from UD 9/10 (HR = 1.56, 95% CI 1.20-2.03, p = 0.0009) but not in those from UD 10/10 (HR = 1.13, p = 0.22) and Haplo donors (HR = 1.12, p = 0.43) compared to MSD. In conclusion, in AML patients undergoing HSCT in CR1 achieved after two induction courses 10/10 UD and Haplo but not 9/10 UD donors are comparable alternatives to MSD.

Defining the role of real-world data in cancer clinical research: The position of the European Organisation for Research and Treatment of Cancer.

The emergence of the precision medicine paradigm in oncology has led to increasing interest in the integration of real-world data (RWD) into cancer clinical research. As sources of real-world evidence (RWE), such data could potentially help address the uncertainties that surround the adoption of novel anticancer therapies into the clinic following their investigation in clinical trials. At present, RWE-generating studies which investigate antitumour interventions seem to primarily focus on collecting and analysing observational RWD, typically forgoing the use of randomisation despite its methodological benefits. This is appropriate in situations where randomised controlled trials (RCTs) are not feasible and non-randomised RWD analyses can offer valuable insights. Nevertheless, depending on how they are designed, RCTs have the potential to produce strong and actionable RWE themselves. The choice of which methodology to employ for RWD studies should be guided by the nature of the research question they are intended to answer. Here, we attempt to define some of the questions that do not necessarily require the conduct of RCTs. Moreover, we outline the strategy of the European Organisation for Research and Treatment of Cancer (EORTC) to contribute to the generation of robust and high-quality RWE by prioritising the execution of pragmatic trials and studies set up according to the trials-within-cohorts approach. If treatment allocation cannot be left up to random chance due to practical or ethical concerns, the EORTC will consider undertaking observational RWD research based on the target trial principle. New EORTC-sponsored RCTs may also feature concurrent prospective cohorts composed of off-trial patients.

The European landscape on allogeneic haematopoeietic cell transplantation in Chronic Lymphocytic Leukaemia between 2009 and 2019: a perspective from the Chronic Malignancies Working Party of the EBMT.

Allogeneic transplantation (allo-HCT) is a curative treatment in CLL whose efficacy including the most severe forms had led to the 2006 EBMT recommendations. The advent after 2014 of targeted therapies has revolutionized CLL management, allowing prolonged control to patients who have failed immunochemotherapy and/or have TP53 alterations. We analysed the pre COVID pandemic 2009-2019 EBMT registry. The yearly number of allo-HCT raised to 458 in 2011 yet dropped from 2013 onwards to an apparent plateau above 100. Within the 10 countries who were under the EMA for drug approval and performed 83.5% of those procedures, large initial differences were found but the annual number converged to 2-3 per 10 million inhabitants during the 3 most recent years suggesting that allo-HCT remains applied in selected patients. Long-term follow-up on targeted therapies shows that most patients relapse, some early, with risk factors and resistance mechanisms being described. The treatment of patients exposed to both BCL2 and BTK inhibitors and especially those with double refractory disease will become a challenge in which allo-HCT remains a solid option in competition with emerging therapies that have yet to demonstrate their long-term effectiveness.

Clinical Impact of Polymerase Chain Reaction-Based Aspergillus and Azole Resistance Detection in Invasive Aspergillosis: A Prospective Multicenter Study.

BACKGROUND: Invasive aspergillosis (IA) by a triazole-resistant Aspergillus fumigatus is associated with high mortality. Real-time resistance detection will result in earlier initiation of appropriate therapy. METHODS: In a prospective study, we evaluated the clinical value of the AsperGenius polymerase chain reaction (PCR) assay in hematology patients from 12 centers. This PCR assay detects the most frequent cyp51A mutations in A. fumigatus conferring azole resistance. Patients were included when a computed tomography scan showed a pulmonary infiltrate and bronchoalveolar fluid (BALf) sampling was performed. The primary end point was antifungal treatment failure in patients with azole-resistant IA. RESULTS: Of 323 patients enrolled, complete mycological and radiological information was available for 276 (94%), and probable IA was diagnosed in 99/276 (36%). Sufficient BALf for PCR testing was available for 293/323 (91%). Aspergillus DNA was detected in 116/293 (40%) and A. fumigatus DNA in 89/293 (30%). The resistance PCR was conclusive in 58/89 (65%) and resistance detected in 8/58 (14%). Two had a mixed azole-susceptible/azole-resistant infection. In the 6 remaining patients, treatment failure was observed in 1. Galactomannan positivity was associated with mortality (P = .004) while an isolated positive Aspergillus PCR was not (P = .83). CONCLUSIONS: Real-time PCR-based resistance testing may help to limit the clinical impact of triazole resistance. In contrast, the clinical impact of an isolated positive Aspergillus PCR on BALf seems limited. The interpretation of the EORTC/MSGERC PCR criterion for BALf may need further specification (eg, minimum cycle threshold value and/or PCR positive on >1 BALf sample).

Prediction of Nonrelapse Mortality in Patients With Acute Myeloid Leukemia and Acute Lymphoblastic Leukemia Receiving Allogeneic Stem Cell Transplantation With Posttransplantation Cyclophosphamide-based Graft Versus Host Disease Prophylaxis.

Graft versus host disease (GVHD) prophylaxis with posttransplantation cyclophosphamide (PTCY) has been established to reduce severe GVHD, and thereby potentially reducing nonrelapse mortality (NRM) after allogeneic stem cell transplantation (alloSCT). We evaluated the predictive capacity of established NRM-risk scores in patients receiving PTCY-based GVHD prophylaxis, and subsequently developed and validated a novel PTCY-specific NRM-risk model. Adult patients (n = 1861) with AML or ALL in first complete remission who received alloSCT with PTCY-based GVHD prophylaxis were included. The PTCY-risk score was developed using multivariable Fine and Gray regression, selecting parameters from the hematopoietic cell transplantation-comorbidity index (HCT-CI) and European Group for Blood and Marrow Transplantation (EBMT) score with a subdistribution hazard ratio (SHR) of ≥1.2 for 2-year NRM in the training set (70% split), which was validated in the test set (30%). The performance of the EBMT score, HCT-CI, and integrated EBMT score was relatively poor for discriminating 2-year NRM (c-statistic 51.7%, 56.6%, and 59.2%, respectively). The PTCY-risk score included 10 variables which were collapsed in 3 risk groups estimating 2-year NRM of 11% ± 2%, 19% ± 2%, and 36% ± 3% (training set, c-statistic 64%), and 11% ± 2%, 18% ± 3%, and 31% ± 5% (test set, c-statistic 63%), which also translated into different overall survival. Collectively, we developed an NRM-risk score for acute leukemia patients receiving PTCY that better predicted 2-year NRM compared with existing models, which might be applicable to the specific toxicities of high-dose cyclophosphamide.