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).

How to select older patients with acute myeloid leukemia fit for intensive treatment?

Outcomes of the treatment of older patients with acute myeloid leukemia (AML) are unsatisfactory due to a higher incidence of negative patient- and disease-related risk factors connected with aging. Prediction of poor tolerance to aggressive treatment and low response to standard intensive chemotherapy are the main root causes why the treatment decision is challenging. For a long time, negative prognostic factors for treatment outcomes, overall survival, and early death such as the age itself, low-performance status, high-comorbidity burden, adverse cytogenetics, and secondary AML have been known, and they are routinely taken into account during therapeutic balance. In consideration of the risk factors and specific laboratory results, prognostic models have been created. Despite the abovementioned facts, the survival of older patients with AML remains very poor, that holds true even for the intensive therapy. For that reason, there is an increased effort to find a better approach how to select patients who would benefit from intensive treatment without decreasing their quality of life through severe complications with risk of high treatment-related mortality. Based on the results of clinical studies, the geriatric assessment could be the missing step which would help select older patients who are really fit for intensive treatment and who will benefit from it the most. This review focuses on the risk factors that should be taken under advisement when the decision about the treatment is made. With reference to the published information, we propose an algorithm how to identify fit, vulnerable, and frail patients.

Dasatinib treatment long-term results among imatinib-resistant/intolerant patients with chronic phase chronic myeloid leukemia are favorable in daily clinical practice.

To evaluate long-term real-life results of dasatinib therapy among chronic phase chronic myeloid leukemia patients resistant or intolerant to imatinib, we retrospectively analyzed data of 118 patients treated in centers participating in the database INFINITY. With median follow-up of 37 months, estimated 5-year cumulative incidences of complete cytogenetic and major molecular responses were 78% and 68%, respectively. The estimated 5-year probability of overall survival (OS) and event-free survival (EFS) were 86% and 83%, respectively. Both OS and EFS were significantly improved among patients with BCR-ABL1 transcript level ≤10% at 3 months. Dasatinib toxicity was tolerable however persistent in almost half our patients, even after years of therapy. Pleural effusion occurred in 29% of patients and was responsible for 30% of dasatinib discontinuations. Our results confirmed very good efficacy and acceptable toxicity of dasatinib in second line setting and support the evidence and importance of high-quality real-life CML patient management.

Clonal hierarchy of main molecular lesions in acute myeloid leukaemia.

Genetic mutations in acute myeloid leukaemia (AML) are assumed to occur in a sequential order; however, the predominant hierarchical roles of specific mutated genes have not been fully described. In this study, we aimed to determine the clonal involvement of the most frequent AML-associated mutations. Using a targeted sequencing panel for 18 genes, we traced changes and relative clonal contribution of mutations in 52 patients. We analysed 35 pairs of diagnosis and relapse samples, 27 pairs of primary samples and corresponding patient-derived xenografts, and 34 pairs of total leukocytes and corresponding isolated primitive cells or blast populations. In both relapse and xenografts, we observed conservation of main leukaemic clones and variability was limited to subclones with late-acquired mutations. AML evolution thus mainly involved modification of subclones while the clonal background remained unchanged. NPM1 mutations were identified as the most probable leukaemia-transformation lesion, remaining conserved in contrast to high variation of accompanying subclonal FLT3 and NRAS mutations. DNMT3A mutations represented the most stable mutations forming a preleukaemic background in most samples. Mutations in genes IDH1/2, TET2, RUNX1, ASXL1 and U2AF1 were detected both as preleukaemic and as subclonal lesions, suggesting a non-specific order of acquisition.

Dendritic Cell-Based Immunotherapy in Advanced Sarcoma and Neuroblastoma Pediatric Patients: Anti-cancer Treatment Preceding Monocyte Harvest Impairs the Immunostimulatory and Antigen-Presenting Behavior of DCs and Manufacturing Process Outcome.

Despite efforts to develop novel treatment strategies, refractory and relapsing sarcoma, and high-risk neuroblastoma continue to have poor prognoses and limited overall survival. Monocyte-derived dendritic cell (DC)-based anti-cancer immunotherapy represents a promising treatment modality in these neoplasias. A DC-based anti-cancer vaccine was evaluated for safety in an academic phase-I/II clinical trial for children, adolescents, and young adults with progressive, recurrent, or primarily metastatic high-risk tumors, mainly sarcomas and neuroblastomas. The DC vaccine was loaded with self-tumor antigens obtained from patient tumor tissue. DC vaccine quality was assessed in terms of DC yield, viability, immunophenotype, production of IL-12 and IL-10, and stimulation of allogenic donor T-cells and autologous T-cells in allo-MLR and auto-MLR, respectively. Here, we show that the outcome of the manufacture of DC-based vaccine is highly variable in terms of both DC yield and DC immunostimulatory properties. In 30% of cases, manufacturing resulted in a product that failed to meet medicinal product specifications and therefore was not released for administration to a patient. Focusing on the isolation of monocytes and the pharmacotherapy preceding monocyte harvest, we show that isolation of monocytes by elutriation is not superior to adherence on plastic in terms of DC yield, viability, or immunostimulatory capacity. Trial patients having undergone monocyte-interfering pharmacotherapy prior to monocyte harvest was associated with an impaired DC-based immunotherapy product outcome. Certain combinations of anti-cancer treatment resulted in a similar pattern of inadequate DC parameters, namely, a combination of temozolomide with irinotecan was associated with DCs showing poor maturation and decreased immunostimulatory features, and a combination of pazopanib, topotecan, and MTD-based cyclophosphamide was associated with poor monocyte differentiation and decreased DC immunostimulatory parameters. Searching for a surrogate marker predicting an adverse outcome of DC manufacture in the peripheral blood complete blood count prior to monocyte harvest, we observed an association between an increased number of immature granulocytes in peripheral blood and decreased potency of the DC-based product as quantified by allo-MLR. We conclude that the DC-manufacturing yield and the immunostimulatory quality of anti-cancer DC-based vaccines generated from the monocytes of patients were not influenced by the monocyte isolation modality but were detrimentally affected by the specific combination of anti-cancer agents used prior to monocyte harvest.

Prognostic significance of mutation profile at diagnosis and mutation persistence during disease remission in adult acute myeloid leukaemia patients.

In this multi-centre study, we analysed the prognostic impact of mutations in 19 genes associated with myeloid malignancies in 258 newly diagnosed acute myeloid leukaemia patients (aged 19-70 years) undergoing intensive therapy. We identified five patient groups with different prognostic risks and different benefits from allogeneic hematopoietic stem cell transplantation (alloHSCT) within the intermediate cytogenetic risk group patients (n = 184). The most adverse prognosis was observed in patients with DNMT3A and FLT3-ITD co-mutation, whose survival could be significantly improved with alloHSCT. In contrast, the most favourable prognosis without any further benefit from alloHSCT was identified in patients with mutations in NPM1 or CEBPA, after exclusion of the unfavourable prognostic groups defined by mutations in DNMT3A, RUNX1 or genes from chromatin/spliceosome group. An additional analysis of 113 diagnosis-remission paired samples revealed that persistence of non-DNMT3A mutations (above 2% VAF) represented a further negative prognostic factor. The proposed model offers a possible molecular stratification and treatment guidance for intermediate cytogenetic risk group patients.

Chromothripsis in acute myeloid leukemia: biological features and impact on survival.

Chromothripsis is a one-step genome-shattering catastrophe resulting from disruption of one or few chromosomes in multiple fragments and consequent random rejoining and repair. This study defines incidence of chromothripsis in 395 newly diagnosed adult acute myeloid leukemia (AML) patients from three institutions, its impact on survival and its genomic background. SNP 6.0 or CytoscanHD Array (Affymetrix®) were performed on all samples. We detected chromothripsis with a custom algorithm in 26/395 patients. Patients harboring chromothripsis had higher age (p = 0.002), ELN high risk (HR) (p < 0.001), lower white blood cell (WBC) count (p = 0.040), TP53 loss, and/or mutations (p < 0.001) while FLT3 (p = 0.025), and NPM1 (p = 0.032) mutations were mutually exclusive with chromothripsis. Chromothripsis-positive patients showed a worse overall survival (OS) (p < 0.001) compared with HR patients (p = 0.011) and a poor prognosis in a COX-HR optimal regression model. Chromothripsis presented the hallmarks of chromosome instability [i.e., TP53 alteration, 5q deletion, higher mean of copy number alteration (CNA), complex karyotype, alterations in DNA repair, and cell cycle] and focal deletions on chromosomes 4, 7, 12, 16, and 17. CBA. FISH showed that chromothripsis is associated with marker, derivative, and ring chromosomes. In conclusion, chromothripsis frequently occurs in AML (6.6%) and influences patient prognosis and disease biology.

Quantitative assessment of the CD26+ leukemic stem cell compartment in chronic myeloid leukemia: patient-subgroups, prognostic impact, and technical aspects.

Little is known about the function and phenotype of leukemic stem cells (LSCs) in chronic myeloid leukemia (CML) or about specific markers that discriminate LSCs from normal hematopoietic stem cells (HSCs). CD26 has recently been described as a specific marker of CML LSCs. In the current study, we investigated this marker in a cohort of 31 unselected CML patients. BCR/ABL1 positivity was analyzed in highly enriched stem cell fractions using fluorescence in situ hybridization (FISH) and reverse transcription PCR (RT-PCR). The proportion of CD26+ LSCs and CD26- HSCs varied considerably among the patients analyzed, and the percentage of CD26+ cells correlated with leukocyte count. The CD26 expression robustly discriminated LSCs from HSCs. This required a strict gating of the stem cell compartment. Thus, in patients with very low LSC or HSC numbers, only the highly sensitive RT-PCR method discriminated between clonal and non-clonal cells, while a robust FISH analysis required larger numbers of cells in both compartments. Finally, our data show that the numbers of CD26+ CML LSCs correlate with responses to treatment with BCR-ABL1 inhibitors.

Analysis of prognostic significance of merkel cell polyomavirus in chronic lymphocytic leukemia.

BACKGROUND: Merkel cell polyomavirus (MCPyV), a ubiquitous DNA tumor virus, has been found to be associated with Merkel cell carcinoma and chronic lymphocytic leukemia (CLL). Previous studies have reported conflicting results on the frequency and potential pathogenetic role of MCPyV in CLL. The aim of this study was to evaluate MCPyV's association with CLL and its prognostic significance. PATIENTS AND METHODS: Between 2006 and 2013, DNA samples obtained from CLL patients (n = 119) before treatment were tested for MCPyV using quantitative real-time polymerase chain reaction analysis and verified by gel electrophoresis. Only samples testing positive by both methods were considered valid. RESULTS: We found that 13 (11%) of 119 CLL cases were positive for MCPyV. Between the groups of MCPyV-positive and -negative patients, there was no significant difference in the sex, age, cytogenetics, presence of p53 defect, or immunoglobulin heavy chain (IGHV) mutational status. In the subset of MCPyV-negative patients, advanced Rai stage (III to IV) was found more frequently, and therapy was initiated more often. There was no difference in overall response rate, median progression-free survival, and overall survival between both groups. We did not observe any new positivity after treatment in initially MCPyV-negative patients. CONCLUSION: This study provides the first analysis of the prognostic role of MCPyV in CLL. MCPyV occurrence seems to be a relatively rare event during the course of CLL. MCPyV is also unlikely to influence the outcome of CLL patients.