De novo accelerated phase of chronic myeloid leukemia should be recognized even in the era of tyrosine kinase inhibitors.

Overall survival of patients classified according to the European LeukemiaNet 2020 classification. Chronic phase (CP), accelerated phase (AP), blast crisis (BC), low risk (LR), intermediate risk (IR), high risk (HR).

Allogeneic stem cell transplantation in patients with multiple myeloma-single center experience.

The standard of care in multiple myeloma (MM) consists of induction chemotherapy followed by autologous stem cell transplant (autoSCT), but this setting doesn't present curative potential. Despite advances in new, efficient, and targeted drugs, allogeneic transplant (aloSCT) remains the modality with curative potential in MM. With the knowledge of high mortality and morbidity related to the treatment in comparison to treatment with novel drugs, there is no consensus in the indication of aloSCT in MM, also the choice of ideal patients profiting from this method is difficult. Therefore, we performed a retrospective unicentric study of 36 unselected consecutive patients transplanted for MM in the University Hospital in Pilsen between the years 2000-2020 in order to define possible variables influencing survival. The median age of the patients was 52 years (38-63) and the distribution of MM subtypes was standard. The majority of the patients were transplanted in the relapse setting, 3 (8.3%) patients in the 1st line setting, and in 7 (19%) patients elective auto-alo tandem transplant was performed. 18 patients (60% of patients with available cytogenetics (CG) had high-risk disease. 12 (33.3%) patients were transplanted with chemoresistant disease (at least PR not reached). With a median follow-up of 85 months, we observed median overall survival (OS) of 30 months (range 10-60) and median progression-free survival (PFS) of 15 months (11-175). 1- and 5-year Kaplan Meier survival probabilities for OS were 55% and 30.5% respectively. During the follow-up, 27 (75%) patients died, 11 (35%) due to treatment-related mortality (TRM), and 16 patients (44%) due to a relapse. 9 (25%) patients were still alive, 3 (8.3%) of them with complete remission (CR), and 6 (16.7%) patients with relapse/progression. Altogether 21 (58%) of the patients relapsed/progressed with a median of 11 months (3-175). Incidence of clinically significant acute graft versus host disease (aGvHD gr. >II) was low (8.3%) and extensive chronic GvHD (cGvHD) developed in 4 patients (11.1%). Univariant analysis proved marginal statistical significance in disease status before aloSCT (chemosensitive × chemoresistant) for OS, favoring patients with the chemosensitive disease (HR 0.43, 95% CI 0.18-1.01, p=0.05), there was no significant impact of high-risk cytogenetics (CG) on survival. No other analyzed parameter was found to be significant. Our findings support the conclusion that aloSCT is able to overcome high-risk CG and that aloSCT still remains a valid treatment choice with acceptable toxicity in well-selected high-risk patients with curative potential, even though often with active disease, but not derogating the quality of life significantly.

[Hemophagocytic lymfohistiocytosis in adults: review and case report]. / Hemofagocytární lymfohistiocytóza u dospelých: review a kazuistika.

Hemophagocytic lymfohistiocytosis (HLH) is rare, life-threatening condition, characterized by excessive activation of immune system with subsequent proinflammatory state resulting in multiorgan failure. Most frequently, it appears in infancy as a primary disorder caused by mutation of immune-regulatory genes. Increasingly, HLH is being diagnosed as a secondary - adult - form, which occurs as a result of aberrant immune response. Viral or bacterial systemic infections, malignancy with a predominance of lymphoproliferative disorders and autoimmune diseases are the most common triggers. Early diagnosis and initiation of therapy is crucial and increase the chance for recovery. HLH is usually presented as multisystem febrile illness, where an extensive differential diagnosis is needed. Diagnosis of HLH is defined by a combination of clinical and laboratory findings, eventually by a proof of specific mutation. The basic mechanism of therapy is an interruption of aberrant immune response by destruction and suppression of T-lymphocytes function. This is mostly achieved by corticosteroid and etoposide therapy. This review summarizes pathophysiology, diagnostics and therapy of HLH. Furthermore, a case-report of 22-years old patient with secondary HLH being manifested predominantly with acute respiratory failure is presented.Key words: acute respiratory failure - hemophagocytic lymphohistiocytosis - HLH-94 - macrophage activation syndrome - MODS.

Centre characteristics and procedure-related factors have an impact on outcomes of allogeneic transplantation for patients with CLL: a retrospective analysis from the European Society for Blood and Marrow Transplantation (EBMT).

The best approach for allogeneic haematopoietic stem cell transplantations (alloHCT) in patients with chronic lymphocytic leukaemia (CLL) is unknown. We therefore analysed the impact of procedure- and centre-related factors on 5-year event-free survival (EFS) in a large retrospective study. Data of 684 CLL patients who received a first alloHCT between 2000 and 2011 were analysed by multivariable Cox proportional hazards models with a frailty component to investigate unexplained centre heterogeneity. Five-year EFS of the whole cohort was 37% (95% confidence interval [CI], 34-42%). Larger numbers of CLL alloHCTs (hazard ratio [HR] 0·96, P = 0·002), certification of quality management (HR 0·7, P = 0·045) and a higher gross national income per capita (HR 0·4, P = 0·04) improved EFS. In vivo T-cell depletion (TCD) with alemtuzumab compared to no TCD (HR 1·5, P = 0·03), and a female donor compared to a male donor for a male patient (HR 1·4, P = 0·02) had a negative impact on EFS, but not non-myeloablative versus more intensive conditioning. After correcting for patient-, procedure- and centre-characteristics, significant variation in centre outcomes persisted. In conclusion, further research on the impact of centre and procedural characteristics is warranted. Non-myeloablative conditioning appears to be the preferable approach for patients with CLL.

Improved relapse-free survival after autologous stem cell transplantation does not translate into better quality of life in chronic lymphocytic leukemia: lessons from the randomized European Society for Blood and Marrow Transplantation-Intergroup study.

In chronic lymphocytic leukemia (CLL) medical progress is driven by clinical studies with relapse-free survival (RFS) as the primary endpoint. The randomized EBMT-Intergroup trial compared high-dose therapy and autologous stem cell transplantation (ASCT) to observation and demonstrated a substantial improvement of RFS without showing improved overall survival for the transplant arm. Here we report quality of life (QoL) information of the first 3 years following randomization from that study. The main objective was to assess the impact of treatment on QoL over time. Two secondary analyses were performed to further investigate the impact of ASCT and relapse on QoL. In the primary analysis, we demonstrate an adverse impact of ASCT on QoL which was largest at 4 months and continued throughout the first year after randomization. Further, we demonstrated a sustained adverse impact of relapse on QoL which worsened over time. Despite better disease control by ASCT the side effects thus turned the net effect towards inferior QoL in the first year and comparable QoL in the following 2 years after randomization. This study emphasizes the importance of information concerning QoL impacts when patients are counseled about treatments aimed at improving RFS in the absence of a survival benefit.

Clinical efficacy and safety of first-line nilotinib or imatinib therapy in patients with chronic myeloid leukemia-Nationwide real life data.

BACKGROUND: To evaluate the outcomes of first-line imatinib versus nilotinib treatment for chronic myeloid leukemia in the chronic phase (CML-CP) in real-world clinical practice. METHODS: A propensity score analysis was performed to eliminate imbalances between the treatment groups. In the analysis, 163 patients in the nilotinib group and 163 patients in the matched imatinib group were retrospectively evaluated. RESULTS: Nilotinib-treated patients achieved complete cytogenetic response (CCyR) and major molecular response more rapidly than imatinib-treated patients. However, there was no significant difference in 5-year overall survival (OS) or progression-free survival (PFS) between the two groups (OS: 94.3% vs. 90.5%, p = 0.602; PFS: 92.9% vs. 88.0%, p = 0.614). Nilotinib-treated patients had a higher failure-free survival (FFS) and event-free survival (EFS) than imatinib-treated patients (FFS: 71.7% vs. 54.3%, p = 0.040; EFS: 71.7% vs. 53.5%, p = 0.025). CONCLUSIONS: This retrospective analysis from clinical practice did not confirm any benefit of frontline nilotinib treatment for OS and PFS; however, it did demonstrate higher FFS and EFS in the nilotinib cohort.

Endothelial Activation and Stress Index (EASIX) to predict mortality after allogeneic stem cell transplantation: a prospective study.

BACKGROUND: We previously reported that the "Endothelial Activation and Stress Index" (EASIX; ((creatinine×lactate dehydrogenase)÷thrombocytes)) measured before start of conditioning predicts mortality after allogeneic hematopoietic stem cell transplantation (alloSCT) when used as continuous score. For broad clinical implementation, a prospectively validated EASIX-pre cut-off is needed that defines a high-risk cohort and is easy to use. METHOD: In the current study, we first performed a retrospective cohort analysis in n=2022 alloSCT recipients and identified an optimal cut-off for predicting non-relapse mortality (NRM) as EASIX-pre=3. For cut-off validation, we conducted a multicenter prospective study with inclusion of n=317 first alloSCTs from peripheral blood stem cell in adult patients with acute leukemia, lymphoma or myelodysplastic syndrome/myeloproliferative neoplasms in the European Society for Blood and Marrow Transplantation network. RESULTS: Twenty-three % (n=74) of alloSCT recipients had EASIX-pre ≥3 taken before conditioning. NRM at 2 years was 31.1% in the high EASIX group versus 11.5% in the low EASIX group (p<0.001). Patients with high EASIX-pre also had worse 2 years overall survival (51.6% vs 70.9%; p=0.002). We were able to validate the cut-off and found that EASIX ≥3 was associated with more than twofold increased risk for NRM in multivariate analysis (HR=2.18, 95% CI 1.2 to 3.94; p=0.01). No statistically significant difference could be observed for the incidence of relapse. CONCLUSIONS: The results of this study provide a prospectively validated standard laboratory biomarker index to estimate the transplant-related mortality risk after alloSCT. EASIX ≥3 taken before conditioning identifies a population of alloSCT recipients who have a more than twofold increased risk of treatment-related mortality.

Listeria monocytogenes Infections in Hematopoietic Cell Transplantation Recipients: Clinical Manifestations and Risk Factors. A Multinational Retrospective Case-Control Study from the Infectious Diseases Working Party of the European Society for Blood and Marrow Transplantation.

Listeriosis is rare after hematopoietic stem cell transplantation (HCT). Little is known about listeriosis in this population. In this retrospective international case-control study, we evaluated 41 listeriosis episodes occurring between 2000 and 2021 in HCT recipients (111 transplant centers in 30 countries) and assessed risk factors for listeriosis by comparisons with matched controls. The 41 listeriosis episodes (all due to Listeria monocytogenes [LM]) occurred in 30 allogeneic (allo)-HCT recipients and 11 autologous (auto)-HCT recipients at a median of 6.2 months (interquartile range [IQR], 1.6 to 19.3 months) post-HCT. The estimated incidence was 49.8/100,000 allo-HCT recipients and 13.7/100,000 auto-HCT recipients. The most common manifestations in our cohort were fever (n = 39; 95%), headache (n = 9; 22%), diarrhea, and impaired consciousness (n = 8 each; 20%). Four patients (10%) presented with septic shock, and 19 of 38 (50%) were severely lymphocytopenic. Thirty-seven patients (90%) had LM bacteremia. Eleven patients (27%) had neurolisteriosis, of whom 4 presented with nonspecific signs and 5 had normal brain imaging findings. Cerebrospinal fluid analysis revealed high protein and pleocytosis (mainly neutrophilic). Three-month mortality was 17% overall (n = 7), including 27% (n = 3 of 11) in patients with neurolisteriosis and 13% (n = 4 of 30) in those without neurolisteriosis. In the multivariate analysis comparing cases with 74 controls, non-first HCT (odds ratio [OR], 5.84; 95% confidence interval [CI], 1.10 to 30.82; P = .038); and lymphocytopenia <500 cells/mm3 (OR, 7.54; 95% CI, 1.50 to 37.83; P = .014) were significantly associated with listeriosis. There were no statistically significant differences in background characteristics, immunosuppression, and cotrimoxazole prophylaxis between cases and controls. HCT recipients are at increased risk for listeriosis compared to the general population. Listeriosis cause severe disease with septic shock and mortality. Neurolisteriosis can present with nonspecific signs and normal imaging. Lymphocytopenia and non-first HCT are associated with an increased risk of listeriosis, and cotrimoxazole was not protective.

Current survival measures reliably reflect modern sequential treatment in CML: correlation with prognostic stratifications.

Using the data of 723 chronic myeloid leukemia (CML) patients in the chronic phase, we analyzed the prognostic value of the Sokal, Euro, and EUTOS scores as well as the level of BCR-ABL1 and the achievement of complete cytogenetic response (CCgR) at 3 months of imatinib therapy in relation to the so-called current survival measures: the current cumulative incidence (CCI) reflecting the probability of being alive and in CCgR after starting imatinib therapy; the current leukemia-free survival (CLFS) reflecting the probability of being alive and in CCgR after achieving the first CCgR; and the overall survival. The greatest difference between the CCI curves at 5 years after initiating imatinib therapy was observed for the BCR-ABL1 transcripts at 3 months. The 5-year CCI was 94.3% in patients with BCR-ABL1 transcripts ≤ 10% and 57.1% in patients with BCR-ABL1 transcripts > 10% (P = 0.005). Therefore, the examination of BCR-ABL1 transcripts at 3 months may help in early identification of patients who are likely to perform poorly with imatinib. On the other hand, CLFS was not significantly affected by the considered stratifications. In conclusion, our results indicate that once the CCgR is achieved, the prognosis is good irrespective of the starting prognostic risks.

Determinants of refined GvHD-free, relapse-free survival after reduced-intensity allogeneic hematopoietic cell transplantation in older patients with myeloid malignancies.

BACKGROUND: Older patients with AML/MDS have a poor prognosis with alloHCT as the only curative option. However alloHCT is challenging given its high TRM. Recently, a composite endpoint of GRFS was proposed to define transplant success. A single centre retrospective analysis was performed to determine the main variables influencing GRFS. PATIENTS AND METHODSMETHODS: 91 consecutive patients≥ 60 years (median 64 years, range 60-74) with AML/MDS who received reduced-intensity alloHCT during 2001-2017 analysed. Disease risk index (DRI) at HCT was low/intermediate in 47pts (52%) and high in 44 pts (48%). RESULTS: After median follow-up for survivors of 56 months (range 7-144), 37 (40.6%) patients were alive. The OS, LFS and GRFS were 61.4%, 58.1%, 49.1% at 1 year and 35.5%, 32.3% and 23.1% at 5 years, respectively. The 1-year and 5-year incidences of NRM and relapse were 26.9%, 21.3% and 47.9% and 35.4%, respectively. In univariate analysis, high DRI was the strongest factor for worse OS (HR 2.121; p = 0.049), LFS (HR 1.924; p = 0.0123) and GRFS (HR 2.319; p = 0.0005). The donor age ≥ 62 years had a negative impact on OS (HR 2.110; p = 0.0345) and GRFS (HR 2.014; p = 0.0341). High DRI (HR 2.652; p = 0.0003) and donor age (HR 2.304; p = 0.0257) retained its significance in multivariate analysis for GRFS. CONCLUSION: A significant portion of older patients with myeloid malignancies survive alloHCT without experiencing GRFS event with DRI as the main determinant of outcome. Negative impact of donor age≥ 62 years suggests preference of a young donor, regardless of being related or unrelated.

Significant oral graft-versus-host disease after allogeneic stem cell transplantation with the FLU/MEL conditioning regimen.

BACKGROUND: Oral graft-versus-host disease (GVHD) is a significant complication after allogeneic stem cell transplantation (SCT) and there is no consistent information about its characteristics in patients after reduced-intensity conditioning regimen FLU/MEL (fludarabine 120 mg/m² and melphalan 140 mg/m²). MATERIAL/METHODS: This was a single-centre prospective observational study of patients after allogeneic SCT with FLU/MEL conditioning performed during the period 1/2005-12/2007. Characteristics of oral GVHD were observed in 71 patients. The observation was discontinued due to death, donor lymphocyte infusion (DLI) or new chemotherapy administration. RESULTS: In 10/2010, the median duration of the observation of the cohort of the patients was 13 (0.2-69) months, and 42 (35-69) months in the still-ongoing 20/71 (28%) patients. Oral acute GVHD had sporadic 7% incidence, whereas oral chronic GVHD was observed in 33% of patients and persisted with median duration of 188 (11-665) days. Clinical and histopathological features were similar in both acute and chronic oral GVHD and included mucosal lichenoid changes, erythema, ulcerations and pseudomembranes, satellite necrosis, apoptotic bodies and lichenoid interface inflammation. CONCLUSIONS: It is necessary to consider complex clinical symptomatology and pathological correlations when classifying the oral GVHD, because local oral symptoms and histopathological features in both acute and chronic oral GVHD forms can be similar. Even though the oral chronic GVHD was mild in the majority of patients, it can be considered as clinically significant due to its incidence, duration and symptomatology. The FLU/MEL conditioning regimen should not be considered as low-risk protocol in this context.

Risk of infectious complications in adult patients after allogeneic hematopoietic stem cell transplantation depending on the site of central venous catheter insertion-multicenter prospective observational study, from the IDWP EBMT and Nurses Group of EBMT.

The current guidelines for prevention of infections in hematopoietic stem cell transplantation (HSCT) do not specify which central venous catheter (CVC) insertion site should be preferred in allogeneic HSCT recipients-internal jugular vein (IJV) or subclavian vein (SCV). We designed a multicenter prospective observational study comparing the risk of infectious and non-infectious complications between the two most common sites of CVC insertion (IJV and SCV) in allogeneic HSCT. There were in total 232 consecutive patients (86 IJV and 146 SCV) who underwent adult allogeneic HSCT reported from 11 centers in 8 countries. The center independent analysis of central line associated/related blood stream infections with ECDC criteria has shown statistically significant difference favoring SCV (23% IJV vs 13% SCV (OR 2.03 (1.01-4.06), p = 0.047)). The differences in CLABSI per 1000 days of CVC use favored SCV over IJV (7.93/1000 days IJV vs 2.79/1000 days SCV, p = 0.002). The frequency of all non-infectious complications was similar in both arms-13% IJV and 12% SCV (OR 1.1 (0.5-2.5), p = 0.8). This multicenter prospective study showed statistically significant lower confirmed number of CLABSI per 1000 days of CVC use without higher risk of noninfectious complications related to the subclavian insertion site in allogeneic HSCT recipients.

Allogeneic Stem Cell Transplantation in Patients With FLT3-ITD Mutated AML: Transplantation in CR1 Is the Decisive Factor for Good Outcome.

BACKGROUND: Patients with internal tandem duplication in fms-related tyrosine kinase receptor gene 3 (FLT3-ITD)-mutated acute myeloid leukemia (AML) have a dismal prognosis and the only curative option seems to be allogeneic stem cell transplantation (alloSCT). However, its timing is still matter of debate. PATIENTS AND METHODS: We retrospectively analyzed 73 consecutive AML patients with FLT3-ITD (median age 53, range 20-68 years) allografted with consistent policy to try to refer them all for upfront alloSCT in first complete remission (CR1). RESULTS: With a median follow-up of 44 (range, 5-135) months the 5-year overall survival (OS)/disease-free survival (DFS) probabilities were 49%/47%. The cumulative incidence of relapse and nonrelapse mortality (NRM) were 37% and 14%, respectively. The estimated 5-year OS for patients who received transplantation in CR1 was 62% versus 0% for patients who received transplantation beyond CR1. Multivariable analysis identified stem cell transplantation beyond CR1 as the key factor for poor OS (hazard ratio [HR], 5.41; P < .0001), DFS (HR, 4.41; P = .0002), and high relapse incidence (HR, 8.08; P < .0001). Acute graft versus host disease Grade ≥3 predicted higher NRM (HR, 3.80; P = .059) as well as inferior OS (HR, 2.04; P = .0079). No association of patient age, nucleophosmin status, donor type, conditioning, and other variables on the survival was detected. CONCLUSION: AlloSCT should be regarded with urgency as soon as CR1 is achieved in this subset of AML patients.

First-line imatinib in elderly patients with chronic myeloid leukaemia from the CAMELIA registry: Age and dose still matter.

We retrospectively evaluated the role of age and dosage in 372 CML patients (170 women, 202 men) treated with first-line imatinib (IMA) from the records of the CAMELIA registry. The median follow-up of the patients was 82.3 (18.0-177.3) months. The treatment results of 80 elderly patients aged over 65 years at diagnosis were compared in analysis "A" with those of 292 younger patients and in analysis "B" with those of 90 patients younger than 40 and 202 patients aged 40-64. The elderly patients had statistically adverse values of the Sokal, ELTS, and ECOG scores and Charlson comorbidity index in both analyses (p from = 0.012 to ≤ 0.001). Despite a more frequent use of a daily dose lower than 400 mg - in 31 elderly patients (38.8%) than in 45 younger ones (15.4%) (p < 0.001), there were no statistically significant differences in the achievement of optimal haematological, cytogenetic, and molecular responses according to the ELN criteria in both the analyses, A and B. The comparisons of overall survival with CML-related death (OSCML) and event-free survival (EFS) were insignificant inanalysis A (p = 0.07 and 0.396, respectively) but progression-free survival (PFS) differed significantly (p = 0.007). In analysis B OSCML and PFS differed significantly (p = 0.027 and 0.003) but EFS was similar (p = 0.351). Elderly patients with a sustained dose of IMA of 400 mg/day have insignificantly better OS, PFS, and EFS compared to patients treated with a lower dosage of IMA. The results in the treatment of the elderly CML patients were comparable with those of the younger ones in terms of the probabilities of the achievement of optimal ELN responses. However, the results for the survival probabilities were influenced by age and the IMA dosage.

Reduced intensity conditioning regimens including alkylating chemotherapy do not alter survival outcomes after allogeneic hematopoietic cell transplantation in chronic lymphocytic leukemia compared to low-intensity non-myeloablative conditioning.

PURPOSE: The optimal dose intensity for conditioning prior to allogeneic hematopoietic stem cell transplantation (alloHSCT) for chronic lymphocytic leukemia (CLL) is unknown. METHODS: We retrospectively compared outcomes of patients who received a first alloHCST after non-myeloablative (NMA) and reduced intensity conditioning (RIC). Data of 432 patients with a median age of 55 years were included, of which 86 patients underwent NMA and 346 RIC. RESULTS: The median follow-up after alloHSCT was 4.3 years. Compared to the RIC group, more NMA patients had purine-analog-sensitive disease, were in complete remission and received matched related donor transplantation. After RIC, the probabilities for 5-year OS, EFS, CIR, and NRM were 46%, 38%, 28%, and 35% and after NMA the respective probabilities were 52%, 43%, 25%, and 32%. In multivariate analysis, remission status prior to conditioning but not RIC versus NMA conditioning had a significant impact on CIR, EFS, and OS. CONCLUSION: Presumed higher anti-leukemic activity of RIC versus NMA conditioning did not translate into better outcomes after alloHSCT, but better remission status prior to conditioning did. Effective pathway inhibitor-based salvage therapies combined with NMA conditioning might thus represent the most attractive contemporary approach for alloHSCT for patients with CLL.

The Role of Cetuximab in the Induction of Anticancer Immune Response in Colorectal Cancer Treatment.

Monoclonal antibodies binding the epidermal growth factor receptor (EGFR), such as cetuximab or panitumumab, are widely used targeted therapeutics for the treatment of patients with colorectal cancer. The clinical significance of these drugs has so far been associated with combined chemotherapy or radiation. It has been shown that these treatment strategies have their clinical limitations and do not fully exploit the immunomodulatory effect of these drugs. In this review, we discuss the mechanisms of immunomodulation together with the anticancer immune response to the monoclonal antibodies targeted to the EGFR. The combination of anti-EGFR monoclonal antibodies with other immunotherapeutic treatment modalities certainly brings new opportunities for targeted therapy in patients with colorectal cancer.

Pre-transplant Quantitative Determination of NPM1 Mutation Significantly Predicts Outcome of AIlogeneic Hematopoietic Stem Cell Transplantation in Patients with Normal Karyotype AML in Complete Remission.

BACKGROUND/AIM: Minimal residual disease (MRD) in patients with acute myeloid leukemia (AML) before allogeneic hematopoietic stem cell transplantation (alloHSCT) can influence the results of therapy. With the aim of evaluating the potential role of pre-transplant MRD, we studied the impact of pre-transplant MRD level on the outcome of alloHSCT in patients with AML in complete remission (CR). PATIENTS AND METHODS: From 2/2005 to 9/2014, 60 patients with a median age of 54 years (range=30-66 years) with normal karyotype-AML harboring nucleophosmin 1 (NPM1) mutation [53% Fms-related tyrosine kinase receptor 3 internal tandem duplication (FLT3/ITD)-positive] in first (n=45) or second (n=15) CR underwent myeloablative (n=16) or reduced-intensity (n=44) alloHSCT (27% related, 73% unrelated). The MRD level was determined from bone marrow samples using real-time polymerase chain reaction for detection of NPM1 mutations before starting the conditioning regimen. RESULTS: The estimated probabilities of 3-year relapse, event-free survival (EFS) and overall survival (OS) for the whole cohort were 28%, 54%, and 59%, respectively. Statistical analysis showed that only age over 63 years and high MRD level affected alloHSCT outcome. Pre-transplant MRD level of 10 mutant copies of NPM1 per 10,000 Abelson murine leukemia viral oncogene homolog 1 (ABL) copies had the strongest statistical significance, and detection of higher MRD level (>10 NPM1-mutant copies) before alloHSCT was associated with increased overall mortality (hazard ratio=3.71; 95% confidence interval=1.55-9.06; p=0.004). The estimated probabilities of 3-year relapse, EFS, and OS were 6%, 72%, and 75% for patients with a low level of MRD and 48%, 35%, and 40% for patients with a higher level. CONCLUSION: Our data showed that the pre-transplant level of MRD in patients with normal karyotype AML harboring NPM1 mutation in CR provides important prognostic information, which as an independent prognostic factor predicts transplant results.

A method to identify new molecular markers for assessing minimal residual disease in acute leukemia patients.

Acute leukemias (AL) comprise a heterogeneous group of hematologic malignancies, and individual patient responses to treatment can be difficult to predict. Monitoring of minimal residual disease (MRD) is thus very important and holds great potential for improving treatment strategies. Common MRD targets include recurrent cytogenetic abnormalities and mutations in important hematological genes; unfortunately well-characterized targets are lacking in many AL patients. Here we demonstrate a technical approach for the identification and mapping of novel clone-specific chromosomal abnormalities down to the nucleotide level. We used molecular cytogenetics, chromosome microdissection, amplification of the microdissected material, and next-generation sequencing to develop PCR-based MRD assays based on unique breakpoint sequences.