Changes in Nutritional Status during Induction Phase and Their Association with Fever and Minimal Residual Disease in Paediatric Acute Lymphoblastic Leukaemia.

Background and objectives: Acute lymphoblastic leukaemia (ALL) is associated with a cytokine imbalance and oxidative stress, which can be aggravated by malnutrition. Malnutrition, defined by the World Health Organisation (WHO) as obesity or undernutrition, can affect treatment complications and outcomes. Therefore, we aimed to analyse the change in the body mass index (BMI) z-score during induction, as well as evaluate the impact of childhood malnutrition on fevers at an ALL presentation and early response to therapy. Methods: An observational cohort study of 50 consecutive children with ALL, diagnosed in 2019-2022, was performed. Patients were divided into age groups of 0-5, 6-11, and 12-17 years. BMI-for-age z-scores were used to define undernutrition and overnutrition according to WHO growth standards. Results: The number of patients with an abnormal BMI increased from 3 (6%) at diagnosis to 10 (20%) at the end of induction (from 2 (4%) to 6 (12%) in overweight/obese, and from 1 (2%) to 4 (8%) in underweight patients). At the end of induction, all overweight/obese patients were 0-5 years old. On the other hand, a statistically significant decrease in the mean BMI z-score among patients aged 12-17 was observed (p = 0.005). The mean BMI z-score differed statistically significantly among children aged 0-5 presenting with and without fever (p = 0.001). The minimal residual disease (MRD) level at the end of induction was not related to BMI at diagnosis. Conclusions: Despite the use of steroids, adolescents are prone to losing weight during an ALL induction, in contrast to preschool children, who tend to gain weight under the same treatment. BMI at diagnosis was related to a fever of ≥38 °C (at ALL presentation) in the 0-5 age group. The results emphasise the importance of careful nutritional status monitoring, with younger and older children as important target groups for weight gain and weight loss interventions, respectively.

Challenges of detecting measurable/minimal disease in acute leukemia.

Measurable/minimal residual disease (MRD) tracking has emerged as a powerful tool for assessing treatment response and predicting outcomes in acute leukemia. However, the clinical and technological challenges associated with MRD tracking must be addressed to improve its utility in routine patient care. This review article aims to provide a summary of the different MRD methodologies used in acute leukemia. It highlights the strengths, diagnostic pitfalls, and clinical utility associated with MRD tracking in this rapidly evolving field.

Determining the Association Between Melanomas and Fields of Melanocytic Dysplasia.

ABSTRACT: Some have proposed that melanomas in situ may be associated with fields of melanocytic dysplasia, particularly on sun-damaged skin, whereas others maintain that the atypical junctional melanocytic hyperplasia (MH) at the periphery of melanomas is simply background junctional MH of sun-damaged skin. The biological potential of atypical junctional MH at the periphery of melanomas is uncertain. We examined whether atypical junctional MH was intrinsic to the melanoma itself (ie, melanoma-associated field of melanocytic dysplasia) or was simply the predictable junctional MH associated with long-standing sun exposure. We retrospectively compared 106 cutaneous melanoma excisions without residual tumor with 105 nonmelanoma cutaneous tumor excisions (ie, basal cell or squamous cell carcinomas) without residual tumor. MH with atypia occurred significantly more frequently in melanoma than in nonmelanoma cutaneous tumor excisions (55.7% vs. 24.8%, P < 0.001). Solar elastosis occurred significantly less frequently in melanoma than in nonmelanoma cutaneous tumor excisions; 33.0% of melanoma excisions and 8.6% of nonmelanoma excision samples exhibited no solar elastosis, respectively (P < 0.001). After controlling for solar elastosis using multivariable linear regression, the association between MH with atypia and melanoma excisions remained significant (P < 0.001). Our results, therefore, demonstrate that melanomas were associated with atypical junctional MH that could not solely be accounted for by the extent of sun damage as measured by solar elastosis.

Outcomes Are Similar After Allogeneic Hematopoietic Stem Cell Transplant for Newly Diagnosed Acute Myeloid Leukemia Patients who Received Venetoclax + Azacitidine Versus Intensive Chemotherapy.

Allogeneic hematopoietic stem cell transplantation (SCT) after a patient with acute myeloid leukemia (AML) achieves a remission from intensive chemotherapy (IC) is given with curative intent. Recently, venetoclax-based regimens have become the standard of care for patients with newly diagnosed AML who are unfit for IC. If these patients achieve remission, they may also be considered for potentially curative consolidation with SCT. There are limited data comparing outcomes after SCT with these different induction strategies. The purpose of the current study was to evaluate depth of remission before SCT and outcomes after SCT in adults with nonrelapsed/refractory AML receiving pre-SCT therapy with either venetoclax/azacitidine (ven/aza) or IC. This was a retrospective, single-institution analysis of 169 patients receiving SCT in first remission after IC or ven/aza. Patient demographics and AML risk features were collected, as well as pre-SCT measurable residual disease (MRD) assessed by flow cytometry and molecular methods. Relapse, transplantation-related mortality, incidence of acute and chronic graft-versus-host-disease (GVHD), and death from any cause were also recorded. Descriptive and survival statistics were applied to these data to compare IC and ven/aza groups. Cox proportional hazard models were used for univariate and multivariate analyses. We demonstrate that despite differences in baseline factors between these groups, outcomes were similar. Relapse-free and overall survival, as well as cumulative incidences of transplantation-related mortality, relapse, and acute and chronic GVHD were comparable between groups. Exploring survival in younger (<65 years) versus older (≥65 years) patients by treatment group did not alter these results. Finally, although pre-SCT MRD by flow cytometry was significantly predictive of post-SCT relapse and survival in the IC + SCT patients, it was not significantly predictive of relapse and survival in the ven/aza + SCT patients. Although these findings require prospective validation in a larger cohort of patients, they suggest that ven/aza followed by SCT is a reasonable management strategy for transplantation candidates at any age.

Association of minimal residual disease with clinical outcomes in Philadelphia chromosome positive acute lymphoblastic leukemia in the tyrosine kinase inhibitor era: A systemic literature review and meta-analysis.

Minimal residual disease (MRD) appeared to be a potent prognostic indicator in patients with Philadelphia chromosome positive acute lymphoblastic leukemia (Ph+ ALL), with potential value in informing individualized treatment decisions. Hence, we performed herein a systemic literature review and meta-analysis to comprehensively address the prognostic value of MRD in Ph+ ALL. Systematic literature review was conducted in PubMed, Embase, and Cochrane databases with the data access date up to September 23, 2020. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated with fixed-effects or random-effects models. Furthermore, subgroup analyses were performed to assess the robustness of the associations. 27 studies with a total number of 3289 patients were eligible for this meta-analysis. Combined HRs suggested that MRD positivity was associated with inferior event-free survival (EFS) (HR = 2.00, 95% CI 1.77-2.26) and overall survival (OS) (HR = 2.34, 95% CI 1.86-2.95). The associations remained statistically significant in subgroup analyses including age group, MRD timing, disease status at MRD, MRD cutoff level, et al. Our findings suggested MRD as a potent clinical tool for assessing the prognosis of Ph+ ALL. Further studies using MRD-based risk stratification might help optimize individualized treatment strategies for Ph+ ALL patients.

Chylopericardium Due to Residual Lymphangiomyoma Detected on 99mTc-Sulfur Colloid Lymphoscintigraphy.

ABSTRACT: Lymphangiomyomas are relatively rare, benign neoplasms. Many patients present with symptoms including effusions, and some cases are incidentally detected. Surgical excision is the treatment of choice, but because of its location, complete surgical resection of a lymphangioma can be technically difficult, and recurrent cases can present with symptoms including effusions. 99mTc-sulfur colloid scan can be used to confirm the leak and nature of the effusion fluid. Here, we present an 8-year-old girl with recurrent pleural and pericardial effusions after lymphocele excision and total pericardiectomy. 99mTc-sulfur colloid lymphoscintigraphy was done to rule out secondary chylopericardium.

Next generation flow cytometry for MRD detection in patients with AL amyloidosis.

The treatment of AL amyloidosis aims to eradicate the plasma cell clone and eliminate toxic free light chain production. Only in a minority of patients the plasma cell clone is completely eradicated; residual light chain production may still exist while clonal relapse may occur. We used sensitive next-generation flow cytometry (NGF) to detect minimal residual disease (MRD) in AL amyloidosis patients at complete haematologic response. MRD evaluation was feasible in 51 of 52 (98%) tested patients and at a median sensitivity of 2.3 × 10-6 MRD was undetectable in 23 (45%). An organ response occurred in 86% of MRDneg vs 77% in MRDpos; renal response in 15/17(88%) of MRDneg vs in 14/16(87.5%) of MRDpos and cardiac response in 10/10(100%) of MRDneg vs 11/15(73%) of MRDpos patients. After a median follow-up of 24 months post MRD testing, no MRDneg patient had a haematologic relapse vs 6/28(21%) MRDpos (p = .029). Pooling haematologic and organ progressions, 9 (32%) MRDpos patients had disease progression vs only 1 (4%) MRDneg patient (p = .026). In conclusion, MRD detection using NGF has profound clinical implications, so that AL patients with undetectable MRD have a very high probability of organ response and a very low probability of haematologic relapse.

Validation of a modified pre-lysis sample preparation technique for flow cytometric minimal residual disease assessment in multiple myeloma, chronic lymphocytic leukemia, and B-non Hodgkin lymphoma.

BACKGROUND: Minimal residual disease (MRD) assessment of hematopoietic neoplasia below 10-4 requires more leukocytes than is usually attainable by post-lysis preparation. However, not all laboratories are resourced for consensus Euroflow pre-lysis methodology. Our study aim was to validate a modified pre-lysis protocol against our standard post-lysis method for MRD detection of multiple myeloma (MM), chronic lymphocytic leukemia (CLL), and B-non Hodgkin lymphoma (B-NHL), to meet demand for deeper MRD assessment by flow cytometry. METHOD: Clinical samples for MRD assessment of MM, CLL, and B-NHL (50, 30, and 30 cases, respectively) were prepared in parallel by pre and post-lysis methods for the initial validation. Total leukocytes, MRD, and median fluorescence intensity of antigen expression were compared as measures of sensitivity and antigen stability. Lymphocyte and granulocyte composition were compared, assessing relative sample processing stability. Sensitivity of the pre-lysis assay was monitored post validation for a further 18 months. RESULTS: Pre-lysis achieved at least 10-4 sensitivity in 85% MM, 81% CLL, and 90% B-NHL samples versus 24%, 48%, and 26% by post-lysis, respectively, with stable antigen expression and leukocyte composition. Post validation over 18 months with technical expertise improving, pre-lysis permitted 10-5 MRD assessment in 69%, 86%, and 82% of the respective patient groups. CONCLUSION: This modified pre-lysis procedure provides a sensitive, robust, time efficient, and relatively cost-effective alternative for MRD testing by MFC at 10-5 , facilitating clinically meaningful deeper response assessment for MM, CLL, and B-NHL. This method adaptation may facilitate more widespread adoption of highly sensitive flow cytometry-based MRD assessment.

MRD May Predict Relapse in NSCLC.

Circulating tumor DNA (ctDNA) may be a useful biomarker for minimal residual disease (MRD) in patients with early-stage non-small cell lung cancer-and MRD may be a good predictor of relapse. In the TRACERx study, a ctDNA assay confirmed MRD negativity in more than 99% of patients-and detected MRD in patients who relapsed before their disease was picked up by standard imaging.

Performance of eight-color dry antibody reagent in the detection of minimal residual disease in chronic lymphocytic leukemia samples.

BACKGROUND: Minimal residual disease (MRD) in chronic lymphocytic leukemia (CLL) has prognostic and predictive significance. One of the approaches to detect MRD by flow cytometry (FC) is the use of dry antibody reagents such as DuraClone® RE CLB (Beckman Coulter-BC). The aim of this study was to evaluate the performance of the DuraClone® RE CLB in detecting MRD in CLL compared to liquid reagents. METHODS: DuraClone® RE CLB is composed by CD81FITC, ROR1PE, CD79bPC5.5, CD19PC7, CD5APC, CD43APCA750, CD20PB, and CD45KrO. For the liquid reagent assay, we used CD43FITC, ROR1PE, CD3ECD, CD5PC5.5, CD20PC7, CD79bAPC, CD19APC750, CD81 APCH7, and CD45KrO. The liquid and dry tubes were used to detect 20 MRD-positive CLL samples. The samples were analyzed using Radar Plots Kaluza Software (BC). RESULTS: The statistical correlation between the liquid and dry reagents was acceptable (R2 = .9583) and no discrepancy was observed in MRD percentages. The average of the total number of acquired events in DuraClone® RE CLB was 758.583 (362.632-2.290.387), which allowed accurate sensitivity for the FC assay. The lowest MRD frequency detected by DuraClone® RE CLB was 0.01%, corresponding to a cluster with 106 events in a total of 737.030. The radar plots allowed the discrimination between normal B-cell population and CLL cells. CONCLUSION: The DuraClone® RE CLB method allowed the accurate detection of MRD in clinical and interlaboratorial CLL samples, thereby supporting the use of this method to potentially increase productivity, reduce pipetting-associated errors and cost, and allow better standardization.

Changing paradigms in the treatment of residual/recurrent head and neck cancer: implications for dysphagia management.

PURPOSE OF REVIEW: Despite advances in head and neck cancer treatment provision, recurrence rates remain high with the added risk of successfully treated patients developing a second primary. We report on the management of dysphagia in the context of residual/recurrent or new disease in a preirradiated field and make suggestions for future research. RECENT FINDINGS: There have been numerous developments in treatment options for people with residual/recurrent head and neck cancer. This is because of improved surgical interventions including microvascular reconstruction techniques and transoral robotic surgery. In the era of highly conformal radiotherapy techniques, such as intensity-modulated radiotherapy (IMRT), there may be opportunities for re-irradiation. These advancements are now increasingly employed in the context of locoregionally recurrent disease. With results being reported from an increasing number of clinical trials, systemic therapies, including treatment with immunotherapy, offer the potential for increased survival with less treatment-related toxicity. SUMMARY: Dysphagia is recognized as a significant toxicity following radical surgical and radiation-based approaches, particularly when multimodal treatment is required. Increasingly, late radiation-associated dysphagia is gaining greater attention in the literature. Many patients presenting with residual and recurrent disease do so against a background of comorbidities as well as persistent and late treatment-related toxicity.

Impact of graft-versus-host disease and graft-versus-leukemia effect based on minimal residual disease in Philadelphia chromosome-positive acute lymphoblastic leukemia.

The impacts of graft-versus-host disease (GVHD) and graft-versus-leukemia (GVL) effect might differ depending on minimal residual disease (MRD). Therefore, we examined 1,022 recipients who underwent their first allogeneic hematopoietic stem cell transplantation (HSCT) for Philadelphia chromosome-positive acute lymphoblastic leukemia (Ph-positive ALL) in first complete remission. MRD status at HSCT was negative in 791 (77·4%) and positive in 231 (22·6%). The impact of GVHD as a time-dependent covariate on transplant outcomes were analyzed while adjusting for other possible variables. Mild acute GVHD [hazard ratio (HR), 0·90; 95% confidence interval (CI), 0·70-1·16; P = 0·901] and chronic GVHD (HR, 0·82, 95% CI, 0·58-1·14; P = 0·238) were not significantly associated with overall mortality, whereas severe acute GVHD (HR, 2·26, 95% CI, 1·64-3·11; P < 0·001) resulted in inferior overall survival due to high non-relapse mortality. Moreover, even in the subgroup analyses stratified according to MRD status, acute and chronic GVHD were not significantly associated with better overall survival. Therefore, less intensive GVHD prophylaxis to achieve a GVL effect is not recommended for Ph-positive ALL.

Extent of Resection and Residual Tumor Thresholds for Postoperative Total Seizure Freedom in Epileptic Adult Patients Harboring a Supratentorial Diffuse Low-Grade Glioma.

BACKGROUND: Epileptic seizures impair quality of life in diffuse low-grade glioma (DLGG) patients. Tumor resection significantly impacts postoperative seizure control, but the precise extent of resection (EOR) required for optimal seizure control is not clear yet. OBJECTIVE: To identify the EOR and residual tumor volume that correlated to postoperative seizure control, defined as a total seizure freedom (Class 1A in reference to Engel classification system) with and without antiepileptic drugs in patients undergoing surgical resection of supratentorial DLGG. METHODS: A retrospective review was conducted of all patients who underwent first-line surgical resection of supratentorial DLGG who presented with preoperative seizures without adjuvant oncological treatment. EOR and residual tumor volume were quantified from pre- and post-operative magnetic resonance imagings. Receiver operating characteristic curves were plotted to determine the EOR and residual tumor volume that corresponded to optimal postoperative seizure control. RESULTS: Of the 346 included patients, 65.5% had controlled seizures postoperatively, with higher age at resection (adjusted OR per unit, 1.03 [95% confidence interval:1.01-1.06], P = .043) and higher percentage of resection (adjusted OR per unit, 1.02 [95% confidence interval:1.00-1.03], P < .001) found as independent predictors of postoperative seizure control. Optimal EOR was ≥91% and optimal residual tumor volume was ≤19 cc to improve postoperative seizure control. CONCLUSION: Postoperative seizure control is more likely when EOR is ≥91% and/or when residual tumor volume is ≤19 cc in supratentorial DLGG gliomas who present with seizures. Resected peritumoral cortex should, however, be taken into account in future studies.

[Methods and clinical values for minimal residual disease detection in patients with multiple myeloma].

The complete response (CR) rates in patients with multiple myeloma (MM) have been rapidly increasing after the approval of novel agents such as proteasome inhibitors, immunomodulatory drugs, histone deacetylase inhibitors, and monoclonal antibodies. Recently, patients administered with a combination of novel agents with autologous stem-cell transplantation achieved a 70% CR rate. The assessment of minimal residual disease (MRD) is necessary for effective stratification of the CR cases and the generation of accurate prognoses. This review summarizes recent topics pertaining to MRD detection methods (multiparameter flow cytometry, allele-specific oligonucleotide real-time quantitative polymerase chain reaction, droplet digital PCR, and next-generation sequencing) and the prognostic value of MRD assessment in patients with MM.

Philadelphia-Like Acute Lymphoblastic Leukemia in Adults.

PURPOSE OF REVIEW: This study aims to provide an overview of the classification, incidence, genomic alterations, and clinical implications of Philadelphia-like Acute Lymphoblastic Leukemia (Ph-like ALL) in adults. RECENT FINDINGS: Ph-like ALL is a high-risk subtype of B cell precursor ALL with characteristic genomic alterations in children and adults. A standard approach for diagnosis is missing and currently mainly based on gene expression analysis. The incidence is age depended and highest in adolescents and younger adults (age 16-39) where 19-28% of patients belong to this subtype. Ph-like ALL is associated with persistence of minimal residual disease (MRD) and inferior prognosis. Some genomic alterations respond to specific treatment approaches and provide hope for tailored therapies. Ph-like ALL in adults is an aggressive and high-risk subtype of B cell precursor ALL. Without consensus definition, diagnosis is difficult and current publications highlight the importance of stringent MRD monitoring to guide risk-adapted treatment strategies.

The acidic microenvironment as a possible niche of dormant tumor cells.

Although surgical excision, chemo-, and radio-therapy are clearly advanced, tumors may relapse due to cells of the so-called "minimal residual disease". Indeed, small clusters of tumor cells persist in host tissues after treatment of the primary tumor elaborating strategies to survive and escape from immunological attacks before their relapse: this variable period of remission is known as "cancer dormancy". Therefore, it is crucial to understand and consider the major concepts addressing dormancy, to identify new targets and disclose potential clinical strategies. Here, we have particularly focused the relationships between tumor microenvironment and cancer dormancy, looking at a re-appreciated aspect of this compartment that is the low extracellular pH. Accumulating evidences indicate that acidity of tumor microenvironment is associated with a poor prognosis of tumor-bearing patients, stimulates a chemo- and radio-therapy resistant phenotype, and suppresses the tumoricidal activity of cytotoxic lymphocytes and natural killer cells, and all these aspects are useful for dormancy. Therefore, this review discusses the possibility that acidity of tumor microenvironment may provide a new, not previously suggested, adequate milieu for "dormancy" of tumor cells.

Minimal Residual Disease in Acute Lymphoblastic Leukemia: How to Recognize and Treat It.

In recent years, the identification of minimal residual disease (MRD) that persists after chemotherapy has emerged as the most powerful tool in determining the prognosis of patients with ALL, often superseding historically relevant prognostic factors. Multiple methods to detect MRD exist, each with their own advantages and disadvantages. Multiparameter flow cytometry and quantitative polymerase chain reaction are the most commonly used methods of MRD detection in clinical practice, although there is promise in the use of more sensitive assays utilizing next-generation sequencing that may be able to further refine MRD-based risk stratification. By accurately identifying patients with persistent MRD who are at highest risk for relapse, we may be able to better design rational post-remission therapies using novel agents, such as inotuzumab ozogamicin, blinatumomab, and CD19-directed chimeric antigen receptor T cells, all of which have been shown to be effective in achieving MRD negativity, even in patients with relapsed or refractory disease. Future studies will be required to determine whether these post-remission strategies can obviate the need for allogeneic stem cell transplantation for patients with ALL in whom MRD can be eradicated.

Next-Generation Sequencing for Minimal Residual Disease Surveillance in Acute Lymphoblastic Leukemia: An Update.

Monitoring minimal residual disease (MRD) is an important predictor of outcome in acute lymphoblastic leukemia (ALL) and is used in risk stratification, prognosis determination, and therapy guidance. Several laboratory techniques have proven utility for characterizing leukemic cells and following MRD through diagnosis, remission and possible recurrence. Methods for determining MRD are based on the detection of leukemia-specific aberrant immunophenotypes by mulitparameter flow cytometry or the evaluation of leukemia-specific rearranged immunoglobulin or T-cell receptor sequences by quantitative real-time PCR. Next-generation sequencing (NGS) is emerging as a new flexible and sensitive tool to detect MRD, which allows identification of clonal composition and scalable sensitivity depending on sequence coverage. As NGS becomes more accessible and affordable, guidelines should be established for its application to MRD surveillance.

Factores pronósticos clínico-biológicos en pacientes con leucemia aguda mieloblástica en recaída / Clinical and biological prognostic factors in relapsed acute myeloid leukemia patients

Fundamentos y objetivo: La leucemia aguda mieloblástica (LAM) constituye la leucemia más frecuente en adultos. A pesar de los avances en el conocimiento de su patogenia, las tasas de curación no superan el 40%, siendo la recaída de la enfermedad la causa más frecuente de fallo de tratamiento. La recaída ocurre por fenómenos de evolución clonal. En este estudio analizamos los factores pronósticos clínicos y biológicos en pacientes adultos con LAM en recaída. Pacientes y métodos: Analizamos un total de 75 pacientes que presentaron recaída leucémica tras haber alcanzado la remisión completa. Se realizó un estudio inmunofenotípico mediante citometría de flujo y estudio citogenético mediante cariotipo convencional en muestras de médula ósea obtenidas en el momento del diagnóstico y de la recaída. Resultados: La supervivencia global (SG) de la serie fue del 3,7%±2,3, siendo la principal causa de muerte la progresión leucémica (83,3%). Los pacientes con recaídas precoces -antes de 12 meses- y aquellos con riesgo citogenético-molecular adverso presentaron SG significativamente inferiores. En el momento de la recaída el 52,5% de los pacientes mostraron cambios fenotípicos, y el 50%, cambios citogenéticos, sin observarse factores clínicos predictivos de dicha evolución clonal. La evolución clonal fenotípica o citogenética no mostró ningún impacto significativo en la SG. Conclusiones: Los pacientes con recaída de LAM presentan un pronóstico infausto, especialmente aquellos con recidiva precoz y riesgo citogenético-molecular adverso. La evolución clonal fenotípica y/o citogenética ocurre en la mitad de los casos sin factores clínicos predictivos ni impacto pronóstico (AU)

Background and objective: Acute myeloid leukemia (AML) is the most frequent type of acute leukemia in adults. Despite recent advances in the characterization of pathogenesis of AML, the cure rates are under 40%, being leukemia relapse the most common cause of treatment failure. Leukaemia relapse occurs due to clonal evolution or clonal escape. In this study, we aimed to analyze the clinical and biological factors influencing outcomes in patients with AML relapse. Patients and methods: We included a total of 75 AML patients who experienced leukaemia relapse after achieving complete remission. We performed complete immunophenotyping and conventional karyotyping in bone marrow aspirates obtained at diagnosis and at leukemia relapse. Results: Overall survival (OS) of the series was 3.7%±2.3, leukaemia progression being the most common cause of death. Patients relapsing before 12 months and those with adverse cytogenetic-molecular risk had statistically significant worse outcomes. A percentage of 52.5 of patients showed phenotypic changes and 50% cytogenetic changes at relapse. We did not find significant clinical factors predicting clonal evolution. The presence of clonal evolution at relapse did not have a significant impact on outcome. Conclusions: Patients with relapsed AML have a dismal prognosis, especially those with early relapse and adverse cytogenetic-molecular risk. Clonal evolution with phenotypic and cytogenetic changes occurred in half of the patients without predictive clinical factors or impact on outcome (AU)