Additional chromosomal abnormalities in Philadelphia-positive clone: adverse prognostic influence on frontline imatinib therapy: a GIMEMA Working Party on CML analysis. Blood. 2012;120:761-767. [PMID: 22692507 DOI: 10.1182/blood-2011-10-384651]

Prognosis in Chronic Myeloid Leukemia: Baseline Factors, Dynamic Risk Assessment and Novel Insights

The introduction of tyrosine kinase inhibitors (TKIs) has changed the treatment paradigm of chronic myeloid leukemia (CML), leading to a dramatic improvement of the outcome of CML patients, who now have a nearly normal life expectancy and, in some selected cases, the possibility of aiming for the more ambitious goal of treatment-free remission (TFR). However, the minority of patients who fail treatment and progress from chronic phase (CP) to accelerated phase (AP) and blast phase (BP) still have a relatively poor prognosis. The identification of predictive elements enabling a prompt recognition of patients at higher risk of progression still remains among the priorities in the field of CML management. Currently, the baseline risk is assessed using simple clinical and hematologic parameters, other than evaluating the presence of additional chromosomal abnormalities (ACAs), especially those at "high-risk". Beyond the onset, a re-evaluation of the risk status is mandatory, monitoring the response to TKI treatment. Moreover, novel critical insights are emerging into the role of genomic factors, present at diagnosis or evolving on therapy. This review presents the current knowledge regarding prognostic factors in CML and their potential role for an improved risk classification and a subsequent enhancement of therapeutic decisions and disease management.

Differential prognostic impact of stratified additional chromosome abnormalities on disease progression among Malaysian chronic myeloid leukemia patients undergoing treatment with imatinib mesylate

The emergence of additional chromosome abnormalities (ACAs) in chronic myeloid leukemia (CML) patients during treatment with a tyrosine kinase inhibitor (TKI) regime is generally associated with resistance to treatment and a sign of disease progression to accelerated phase or blast phase. We report the type, frequency, and differential prognostic impact of stratified ACAs with treatment response in 251 Malaysian CML patients undergoing TKI therapy. ACAs were observed in 40 patients (15.9%) of which 7 patients (17.5%) showed ACAs at time of initial diagnosis whereas 33 patients (82.5%) showed ACAs during the course of IM treatment. In order to assess the prognostic significance, we stratified the CML patients with ACAs into four groups, group 1 (+8/+Ph), group 2 (hypodiploidy), group 3 (structural/complex abnormalities); group 4 (high-risk complex abnormalities), and followed up the disease outcome of patients. Group 1 and group 2 relatively showed good prognosis while patients in group 3 and group 4 had progressed or transformed to AP or blast phase with a median survival rate of 12 months after progression. Novel ACAs consisting of rearrangements involving chromosome 11 and chromosome 12 were found to lead to myeloid BP while ACAs involving the deletion of 7q or monosomy 7 led toward a lymphoid blast phase. There was no evidence of group 2 abnormalities (hypodiploidy) contributing to disease progression. Compared to group 1 abnormalities, CML patients with group 3 and group 4 abnormalities showed a higher risk for disease progression. We conclude that the stratification based on individual ACAs has a differential prognostic impact and might be a potential novel risk predictive system to prognosticate and guide the treatment of CML patients at diagnosis and during treatment.

Outcome prediction of chronic myeloid leukemia (CML) in children

We evaluated the feasibility of existing risk assessment tools for chronic myeloid leukemia (CML) in children. Fifty-five patients with newly diagnosed CML between 1996 and 2019 were included. Forty-nine patients presented in chronic phase, thirty-six of whom were treated with upfront tyrosine kinase inhibitor (CP-TKI group); one presented in accelerated phase and four in blastic phase. Treatment, survival, responses, and tolerance were evaluated. All patients in the CP-TKI group received imatinib as their first TKI treatment. The 10-year overall survival (OS), progression-free survival (PFS), and event-free survival (EFS) of TKI-treated group was 97%, 91.4%, and 72.3%, respectively. At 60 months, the rates of major molecular response were 81.2% and deep molecular response was 67.5%. The EUTOS long-term survival (ELTS) risk grouping did not predict OS, PFS, or EFS. The IMAFAIL risk groups were correlated with the risk of imatinib failure. Further studies are required to modify the existing risk assessment tools for children.

Effects of tyrosine kinase inhibitors for controlling Ph+ clone and additional clonal abnormalities in a chronic myeloid leukemia

Purpose

The chronic myeloid leukemia (CML) is characterized by the presence of t(9;22)(q34;q11) that results in chimerization of BCR and ABL genes on the rearranged chromosome 22 or Philadelphia chromosome (Ph). Imatinib has been established as the first line of therapy for CML; in case of Imatinib failure or resistance, other second or third generation tyrosine kinase inhibitors (TKIs) are considered. However, acquisition of additional clonal abnormalities (ACAs) interferes in management of CML. We described a complex scenario of cytogenetic remission, relapse, response to TKIs and behavior of ACAs in a case of CML.

Materials and Methods

Conventional G-banding and FISH cytogenetics, and quantitative PCR studies were conducted in the bone marrow for diagnosis and follow up (FU) of the changes of BCR-ABL gene and ACAs at different time intervals.

Results

Ph- chromosome disappeared within 6 months of Imatinib therapy, and re-appeared within a year. Subsequent change of TKI to dasatinib eliminated the Ph+ clone, but established an ACA with trisomy 8 (+8). Further change to Nilotinib, eliminated +8 clone, but re-emergence of Ph+ clone occurred with an ACA with monosomy 7 (-7). Reinstate of Dasatinib eliminated Ph+ and -7 clones, but with gradual reappearance of Ph+ and +8 clones. The patient discontinued FU, though participated in a long term examination.

Conclusion

The complexity of ACAs and Ph+ clones needs frequent monitoring with changes of TKI and technologies.

The Cytogenetic Landscape of Pediatric Chronic Myeloid Leukemia Diagnosed in Chronic Phase

Simple Summary

Philadelphia chromosome-positive chronic myeloid leukemia (CML) is characterized by the translocation of the chromosomes 9 and 22. Additional non-Philadelphia aberrations of chromosomes (nPhAs) and their prognostic relevance for the disease course are comparably well known in adult patients with CML. However, due to the rarity of CML in children and adolescents, nPhAs have hardly been determined systematically in these age groups. Here, we present a large analysis of nPhAs detected in a cohort of 161 patients younger than 18 years who had been diagnosed with CML in chronic phase and enrolled in the German national CML-PAED-II registry. We found a distinct distribution of nPhAs in this pediatric cohort with possible impact on treatment response whereas the survival remained unaffected. Our findings emphasize differences in the disease biology between pediatric and adult patients and prompt further joint international efforts to acquire more data on the disease in this age group.

Abstract

Philadelphia chromosome-positive chronic myeloid leukemia (CML) is cytogenetically characterized by the classic translocation t(9;22)(q34;q11), whereas additional non-Philadelphia aberrations (nPhAs) have been studied extensively in adult patients with CML, knowledge on nPhAs in pediatric patients with CML is still sparse. Here, we have determined nPhAs in a cohort of 161 patients younger than 18 years diagnosed with chronic phase CML and consecutively enrolled in the German national CML-PAED-II registry. In 150 cases (93%), an informative cytogenetic analysis had been performed at diagnosis. In total, 21 individuals (13%) showed nPhAs. Of these, 12 (8%) had a variant translocation, 4 (3%) additional chromosomal aberrations (ACAs) and 5 (3%) harbored a complex karyotype. Chromosome 15 was recurrently involved in variant translocations. No significant impact of the cytogenetic subgroup on the time point of cytogenetic response was observed. Patients with a complex karyotype showed an inferior molecular response compared to patients carrying the classic translocation t(9;22)(q34;q11), variant translocations or ACAs. No significant differences in the probability of progression-free survival and overall survival was found between patients with nPhAs and patients with the classic Philadelphia translocation only. Our results highlight the distinct biology of pediatric CML and underline the need for joint international efforts to acquire more data on the disease pathogenesis in this age group.

High incidence of minor and micro breakpoints in Chronic Myeloid Leukaemia with additional cytogenetic abnormalities at diagnosis – the Western Australian series

Introduction and objective

Chronic Myeloid Leukaemia (CML) is defined by the presence of the Philadelphia chromosome, a balanced translocation between chromosomes 9 and 22 that results in the constitutively active tyrosine kinase, BCR-ABL1. Additional chromosomal abnormalities (ACAs) at diagnosis occur in 5–10% of CML patients, and are important for prognosis. They are classified as major or minor route. The purpose of our study was to determine the frequency and type of ACAs in 193 newly diagnosed CML patients, and to evaluate patient characteristics, treatment response, and survival.

Methods

Medical records, in conjunction with data from the PathWest cytogenetics and molecular laboratories, were analysed.

Results

ACAs were present in 14 (7.3%) of patients at diagnosis. Seven patients had major-route abnormalities, with additional chromosome 8 (+8) the most common. All patients were treated with tyrosine kinase inhibitors (TKIs). Three patients presented in blast crisis; two patients have died. Of note, there was a high incidence of the rare minor and micro BCR-ABL1 fusion transcripts.

Conclusions

Frequency of ACAs at diagnosis was similar to that of previous reports. These patients consist a higher-risk cohort, and require individualised treatment, with consideration of frontline and secondary TKIs, adjunct chemotherapy, novel agents, and allogeneic stem cell transplant.

Genomic Copy Number Variants in CML Patients With the Philadelphia Chromosome (Ph+): An Update

Background

Submicroscopic segmental imbalances detected by array-comparative genomic hybridization (array-CGH) were discovered to be common in chronic myeloid leukemia (CML) patients with t(9;22) as the sole chromosomal anomaly. To confirm the findings of the previous study and expand the investigation, additional CML patients with t(9;22) as the sole chromosomal anomaly were recruited and copy number variants (CNVs) were searched for.

Methods

Karyotyping tests were performed on 106 CML patients during January 2010-September 2019 in our Genetics Laboratory. Eighty-four (79.2%) patients had the Philadelphia (Ph) chromosome as the sole chromosomal anomaly. Only 49(58.3%) of these 84 patients had sufficient marrow or leukemia blood materials to additionally be included in the array-CGH analysis. Fluorescence in situ hybridization (FISH) was carried out to confirm the genes covered by the deleted or duplicated regions of the CNVs.

Results

11(22.4%) out of the 49 patients were found to have one to three somatic segmental somatic segmental (CNVs), including fourteen deletions and three duplications. The common region associated with deletions was on 9q33.3-34.12. Identified in five (45.5%) of the 11 positive patients with segmental CNVs, the deletions ranged from 106 kb to 4.1 Mb in size. Two (18.2%) cases had a deletion in the ABL1-BCR fusion gene on der (9), while three (27.3%) cases had a deletion in the ASS1 gene. The remaining CNVs were randomly distributed on different autosomes.

Conclusion

Subtle genomic CNVs are relatively common in CML patients without cytogenetically visible additional chromosomal aberrations (ACAs). Long-term studies investigating the potential impact on patient prognosis and treatment outcome is underway.

[Analysis of clinical features and prognosis of patients with chronic myelogenous leukemia harboring additional chromosomal abnormalities in Ph-positive cells]

目的

探讨Ph阳性附加染色体异常（ACA/Ph⁺）对初诊慢性期（CP）和治疗中进展为加速期和急变期慢性髓性白血病（CML-AP/BP）患者生物学特征、疗效和预后的影响。

方法

回顾性分析2013年1月至2020年6月河南省人民医院收治的410例Ph⁺ CML[初诊CML-CP 348例，治疗中进展为AP/BP（进展期CML）62例]患者的临床资料，根据ELN2020标准将其分为高危、非高危和无ACA/Ph⁺三组，并比较分析高危/非高危ACA/Ph⁺对其生物学特征、疗效和预后的影响。

结果

①348例初诊CML-CP患者，合并ACA/Ph⁺者20例（5.75%），其中高危ACA/Ph⁺组3例，非高危ACA/Ph⁺组17例；无ACA/Ph⁺组328例。伴ACA/Ph⁺和无ACA/Ph⁺组患者的基本临床特征差异无统计学意义（P值均>0.05）；非高危ACA/Ph⁺组和无ACA/Ph⁺组间完全血液学缓解（CHR）率、完全细胞遗传学反应（CCyR）率、主要分子学反应（MMR）率和5年总生存（OS）率差异均无统计学意义（P值均>0.05）；非高危ACA/Ph⁺组5年无进展生存（PFS）率显著低于无ACA/Ph⁺组（42.0%对74.5%，χ²＝4.766，P＝0.029）。②62例进展期CML患者，合并ACA/Ph⁺者41例（66.13%），其中高危ACA/Ph⁺组28例，非高危ACA/Ph⁺组13例；无ACA/Ph⁺组21例。高危ACA/Ph⁺组患者中位PLT水平（42.5×10⁹/L）低于非高危（141×10⁹/L）和无ACA/Ph⁺组（109×10⁹/L）（χ²＝4.968，P＝0.083）；三组间ABL激酶区点突变发生率差异无统计学意义（P＝0.652）。高危ACA/Ph⁺组CCyR率显著低于无ACA/Ph⁺组（5.3%对46.7%，χ²＝5.851，P＝0.016）。高危ACA/Ph⁺组5年OS率为46.2%，非高危ACA/Ph⁺组为64.3%，无ACA/Ph⁺组为77.8%，其中高危ACA/Ph⁺组患者5年OS率明显低于无ACA/Ph⁺组（χ²＝3.878，P＝0.049）。亚组分析显示高危Ⅰ组（+8，+Ph或含+8/+Ph的复杂ACA）CML患者的5年OS率为54.5%，与无ACA/Ph⁺组相比差异无统计学意义（χ²＝1.514，P＝0.219）；高危Ⅱ组[含−7/7q−或i（17q）或含2个及以上高危ACA的复杂核型]为28.6%，显著低于无ACA/Ph⁺组（χ²＝8.035，P＝0.005）。

结论

因ACA类型和疾病分期不同，伴ACA/Ph⁺ CML患者的治疗反应和预后存在差异，治疗过程中高危ACA的出现意味着更差的治疗反应和预后，严格、规范的细胞遗传学监测对此类患者的早期发现和精准诊疗具有重要意义。

Measuring prognosis in chronic myeloid leukemia: what's new?

Introduction: The outcome of chronic myeloid leukemia (CML) patients in chronic phase has changed after the introduction of tyrosine kinase inhibitors (TKIs). The life expectancy is actually similar to that of the general population. Prognostic stratification at baseline is part of a patient-centered approach to decide the best therapeutic approach.Areas covered: In this review, the current prognostic factors examined at baseline are detailed and the meaning is explained. A broad research on Medline, Embase and archives from EHA and ASH congresses, was performed. Prognostic factors have been divided into patient-related (age, gender, comorbidities, etc.) and disease-related (additional cytogenetic abnormalities, type of transcript, etc). New information about genomic data and the potential role of patient-reported outcomes is also discussed.Expert Opinion: Prognostic factors at baseline should be considered to evaluate the long-term probability of disease-related death, the possible toxicity, and the projected long-term overall survival. The genomic assessment would provide the basis for a genomic-based risk and help in oriented decision-making process.

Chronic Myeloid Leukemia: Modern therapies, current challenges and future directions

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm caused by a reciprocal translocation [t(9;22)(q34;q11.2)] that leads to the fusion of ABL1 gene sequences (9q34) downstream of BCR gene sequences (22q11) and is cytogenetically visible as Philadelphia chromosome (Ph). The resulting BCR/ABL1 chimeric protein is a constitutively active tyrosine kinase that activates multiple signaling pathways, which collectively lead to malignant transformation. During the early (chronic) phase of CML (CP-CML), the myeloid cell compartment is expanded, but differentiation is maintained. Without effective therapy, CP-CML invariably progresses to blast phase (BP-CML), an acute leukemia of myeloid or lymphoid phenotype. The development of BCR-AB1 tyrosine kinase inhibitors (TKIs) revolutionized the treatment of CML and ignited the start of a new era in oncology. With three generations of BCR/ABL1 TKIs approved today, the majority of CML patients enjoy long term remissions and near normal life expectancy. However, only a minority of patients maintain remission after TKI discontinuation, a status termed treatment free remission (TFR). Unfortunately, 5-10% of patients fail TKIs due to resistance and are at risk of progression to BP-CML, which is curable only with hematopoietic stem cell transplantation. Overcoming TKI resistance, improving the prognosis of BP-CML and improving the rates of TFR are areas of active research in CML.

Rare monosomy 7 and deletion 7p at diagnosis of chronic myeloid leukemia in accelerated phase

Clonal cytogenic evolution with the development of additional chromosomal abnormalities (ACAs) in chronic myelogenous leukemia (CML) is a marker for disease progression and is known to impact therapy and survival. The presence of ACAs has been shown to affect the responses to tyrosine kinase inhibitors (TKI) in patients with newly diagnosed CML in accelerated phase (CML-AP). We report a rare case of a CML patient who presented in CML-AP and was found to have multiple ACAs including monosomy 7, deletion 7p, trisomy 8, and an extra Philadelphia chromosome (Ph) in separate Ph-positive cell line, respectively. Six months after combined chemotherapy with TKI, the patient achieved a major cytogenetic response with disappearance of monosomy 7/deletion 7p with no major molecular response.

The EUTOS long-term survival score predicts disease-specific mortality and molecular responses among patients with chronic myeloid leukemia in a practice-based cohort

The European Treatment and Outcome Study (EUTOS) long‐term survival (ELTS) score predicts disease‐specific death in patients with chronic myeloid leukemia (CML) being treated with imatinib during the chronic phase (CP) of the disease. However, it is unclear whether the ELTS score predicts CML‐related events or treatment responses. This study evaluated the predictive value of the ELTS score regarding prognosis and treatment response in patients with CML‐CP. Clinical data were retrospectively obtained from patients enrolled in the CML Cooperative Study Group (CML‐CSG), which included patients diagnosed with CML‐CP from April 2001 to January 2016, and treated with any tyrosine kinase inhibitor (TKI) as first‐line therapy. Among 342 eligible patients, the ELTS scores indicated low‐, intermediate‐, and high‐risk in 74%, 21%, and 5% of patients, respectively. Patients with high ELTS scores had significantly higher disease‐specific mortality and worse event‐free survival, progression‐free survival, and overall survival. Among four risk scores, including the Sokal, Hasford, EUTOS, and ELTS scores, risk stratification by the ELTS score had the highest predictive value in assessing patient prognosis, and also in treatment responses. In fact, the EUTOS and ELTS scores were able to predict the major molecular response within 12 months. Most importantly, the ELTS score was the only scoring system that predicted deep molecular response at any time, regardless of risk level (65.0%, 43.7%, and 23.5% in low‐, intermediate‐, and high‐risk groups, respectively). Compared to other risk scores, the ELTS score was the most sensitive risk classification tool for the four endpoints of interest in this study, as well as molecular responses in patients with CML‐CP.

Efficacy and safety profile of generic imatinib in patients with newly diagnosed chronic myeloid leukemia-chronic phase: sharing experience of a hemato-oncology center from eastern India

In India, CML is the commonest adult leukemia. Imatinib is the gold standard for frontline treatment of newly diagnosed CML-CP patients. The present study was conducted to assess the efficacy and safety of generic imatinib in newly diagnosed CML-CP patients. In this prospective study, 76 newly diagnosed CML-CP patients received generic imatinib. They were monitored as per the ELN2013 recommendation. Karyotyping and BCR-ABL transcript level were done at specified time points. Adverse effects, if any, were documented as per the NCI-CTCAE criteria v4.03. Statistical analysis was done using standard methods. A total of 76 patients included in the study; median age was 36 years. The most common (71%) presenting symptom was fatigue; splenomegaly was found in all patients. CHR was achieved in 97% cases. At 3 months, 64.5% patients achieved ERM. At 6 months, CCyR and MCyR had seen in 65% and 68% cases, respectively. MMR achieved at 12 months in 44% cases. Most common hematological and non-hematological toxicity were anemia and skin changes seen in 89.5% and 71% cases, respectively. With generic imatinib therapy, the results of treatment outcome and safety profile were comparable with original imatinib. The added advantage was gross reduction in cost of therapy meeting unmet needs in CML patients in countries with resource constraints.

Managing chronic myeloid leukemia for treatment-free remission: a proposal from the GIMEMA CML WP

Several papers authored by international experts have proposed recommendations on the management of BCR-ABL1+ chronic myeloid leukemia (CML). Following these recommendations, survival of CML patients has become very close to normal. The next, ambitious, step is to bring as many patients as possible into a condition of treatment-free remission (TFR). The Gruppo Italiano Malattie EMatologiche dell'Adulto (GIMEMA; Italian Group for Hematologic Diseases of the Adult) CML Working Party (WP) has developed a project aimed at selecting the treatment policies that may increase the probability of TFR, taking into account 4 variables: the need for TFR, the tyrosine kinase inhibitors (TKIs), the characteristics of leukemia, and the patient. A Delphi-like method was used to reach a consensus among the representatives of 50 centers of the CML WP. A consensus was reached on the assessment of disease risk (EUTOS Long Term Survival [ELTS] score), on the definition of the most appropriate age boundaries for the choice of first-line treatment, on the choice of the TKI for first-line treatment, and on the definition of the responses that do not require a change of the TKI (BCR-ABL1 ≤10% at 3 months, ≤1% at 6 months, ≤0.1% at 12 months, ≤0.01% at 24 months), and of the responses that require a change of the TKI, when the goal is TFR (BCR-ABL1 >10% at 3 and 6 months, >1% at 12 months, and >0.1% at 24 months). These suggestions may help optimize the treatment strategy for TFR.

The Hidden Pathogenesis of CML: Is BCR-ABL1 the First Event?

PURPOSE OF REVIEW

Identification of the BCR-ABL1 fusion oncogene in patients diagnosed with chronic myeloid leukemia (CML) led to the development of targeted therapy responsible for the dramatic survival benefits observed in the past two decades. However, despite these revolutionary findings, there remains marked disparity in patient outcomes. Why do some patients present de novo while others evolve to the more aggressive stages of CML? Why can select patients successfully discontinue therapy as part of a treatment-free remission attempt whereas others fail to meet specific molecular milestones?

RECENT FINDINGS

BCR-ABL1 kinase mutations are only identified in approximately 50% of patients with poor responses and disease progression, suggesting the presence of alternative resistance mechanisms. Numerous institutions have identified the presence of additional genomic events in addition to BCR-ABL1 with the increasing availability of next-generation sequencing. We explore the potential pathways and events that may cooperate with BCR-ABL1 to answer these questions but also challenge the fundamental tenet that BCR-ABL1 is always the sole event initiating CML.

Additional chromosomal abnormalities in Philadelphia positive chronic myeloid leukemia

Objective

To determine the frequency of additional chromosomal abnormalities in Philadelphia chromosome positive Chronic Myeloid Leukemia (CML) by conventional cytogenetic analysis.

Methods

This descriptive cross sectional study was conducted at Armed Forces Institute of Pathology (AFIP), Rawalpindi, from January 2012 to December 2016. A total number of 528 newly diagnosed CML patients were included in the study. The subjects were tested for the presence of Philadelphia (Ph) chromosome and other additional cytogenetic abnormalities by conventional cytogenetic analysis interpreted according to International System of Human Cytogenetic Nomenclature (ISCN) criteria. Molecular analysis for BCR-ABL was also performed for each patient. The additional cytogenetic abnormalities were then classified into major route abnormalities and minor route abnormalities.

Results

Out of the 528 newly diagnosed CML patients, 378 (71.6%) were males and 150 (28.4%) were females. The age of patients ranged between 18 to 74 years. Four hundred and ninety-eight (94.3%) patients showed Philadelphia chromosome on karyotyping while 30 (5.7%) were negative for the Philadelphia chromosome. On analysis of these 498 Philadelphia positive patients, additional cytogenetic aberrations were detected in 26 (4.9%) patients. Of these, 7 (1.3%) had major route abnormalities while 19 (3.6%) had minor route abnormalities.

Conclusion

The frequency of additional chromosomal abnormalities in our study were not in accordance with previous local and international studies.

Mechanisms of Disease Progression and Resistance to Tyrosine Kinase Inhibitor Therapy in Chronic Myeloid Leukemia: An Update

Chronic myeloid leukemia (CML) is characterized by the presence of the BCR-ABL1 fusion gene, which encodes a constitutive active tyrosine kinase considered to be the pathogenic driver capable of initiating and maintaining the disease. Despite the remarkable efficacy of tyrosine kinase inhibitors (TKIs) targeting BCR-ABL1, some patients may not respond (primary resistance) or may relapse after an initial response (secondary resistance). In a small proportion of cases, development of resistance is accompanied or shortly followed by progression from chronic to blastic phase (BP), characterized by a dismal prognosis. Evolution from CP into BP is a multifactorial and probably multistep phenomenon. Increase in BCR-ABL1 transcript levels is thought to promote the onset of secondary chromosomal or genetic defects, induce differentiation arrest, perturb RNA transcription, editing and translation that together with epigenetic and metabolic changes may ultimately lead to the expansion of highly proliferating, differentiation-arrested malignant cells. A multitude of studies over the past two decades have investigated the mechanisms underlying the closely intertwined phenomena of drug resistance and disease progression. Here, we provide an update on what is currently known on the mechanisms underlying progression and present the latest acquisitions on BCR-ABL1-independent resistance and leukemia stem cell persistence.

Impact of Additional Chromosomal Aberrations Present at Diagnosis on Outcome of Adolescent and Young Adult Chronic Myeloid Leukemia Patients: A Single Center Experience

Studying the influence of additional chromosomal aberrations (ACAs) present at diagnosis on the outcome of adolescent and young adult (AYA) chronic myeloid leukemia (CML) patients as it has not been addressed previously. Eighty-six AYA CML patients have been analyzed for occurrence of ACAs at diagnosis through performing bone marrow karyotyping. All patients received imatinib mesylate upon diagnosis of CML. Overall response, molecular response, survival status, progression and occurrence of events were monitored during the follow up period. There was a statistically significant difference between patients with and without ACAs regarding overall response (P = 0.049). There was insignificant difference between the two groups regarding achievement of major molecular response (MMR) (P = 0.594), MR⁴ (P = 0.282) and MR^4.5 (P = 0.704). There was a significant difference between patients with and without ACAs regarding time to MMR (P = 0.042) and time to MR⁴ (P = 0.048) but not regarding time to MR^4.5 (P = 0.065). There was insignificant impact of ACAs at diagnosis on overall survival (P = 0.152), progression free survival (P = 0.112), failure free survival (P = 0.114), event free survival (P = 0.194) and alternative treatment free survival (P = 0.731). The presence of ACAs at diagnosis does not signal worse prognosis in AYA CML patients but it may delay molecular response to imatinib mesylate.

Early Management of CML

PURPOSE OF REVIEW

The marked improvement in clinical outcomes for patients with chronic myeloid leukaemia (CML) can be solely attributed to the introduction of targeted therapies against the fusion oncoprotein, BCR-ABL1. However, patient responses, although generally positive, remain heterogenous. Careful drug selection, ensuring the optimal TKI, is chosen for each patient and involves a complex decision process which incorporates consideration of numerous factors.

RECENT FINDINGS

For some patients, with disease characteristics that indicate adverse intrinsic disease biology, more potent BCR-ABL1 inhibition is often appropriate, whereas other patients with major co-morbidities will benefit from a less aggressive approach to avoid life-shortening toxicities. For the vast majority of patients, the long-term goal of therapy will be the achievement of a deep molecular response and subsequent treatment-free remission and this consideration will play a large part in the drug selection process. We explore early management of CML, from the first presentation through to frontline therapy selection.

Management of Chronic Myeloid Leukemia in Advanced Phase

Management of chronic myeloid leukemia (CML) in advanced phases remains a challenge also in the era of tyrosine kinase inhibitors (TKIs) treatment. Cytogenetic clonal evolution and development of resistant mutations represent crucial events that limit the benefit of subsequent therapies in these patients. CML is diagnosed in accelerated (AP) or blast phase (BP) in <5% of patients, and the availability of effective treatments for chronic phase (CP) has dramatically reduced progressions on therapy. Due to smaller number of patients, few randomized studies are available in this setting and evidences are limited. Nevertheless, three main scenarios may be drawn: (a) patients diagnosed in AP are at higher risk of failure as compared to CP patients, but if they achieve optimal responses with frontline TKI treatment their outcome may be similarly favorable; (b) patients diagnosed in BP may be treated with TKI alone or with TKI together with conventional chemotherapy regimens, and subsequent transplant decisions should rely on kinetics of response and individual transplant risk; (c) patients in CP progressing under TKI treatment represent the most challenging population and they should be treated with alternative TKI according to the mutational profile, optional chemotherapy in BP patients, and transplant should be considered in suitable cases after return to second CP. Due to lack of validated and reliable markers to predict blast crisis and the still unsatisfactory results of treatments in this setting, prevention of progression by careful selection of frontline treatment in CP and early treatment intensification in non-optimal responders remains the main goal. Personalized evaluation of response kinetics could help in identifying patients at risk for progression.

Heterogeneous BCR-ABL1 signal patterns identified by fluorescence in situ hybridization are associated with leukemic clonal evolution and poorer prognosis in BCR-ABL1 positive leukemia

Background

Although extensive use of tyrosine kinase inhibitors has resulted in high and durable response rate and prolonged survival time in patients with BCR-ABL1 positive chronic myeloid leukemia (CML) and acute leukemia, relapse and drug resistance still remain big challenges for clinicians. Monitoring the expression of BCR-ABL1 fusion gene and identifying ABL kinase mutations are effective means to predict disease relapse and resistance. However, the prognostic impact of BCR-ABL1 signal patterns detected by fluorescence in situ hybridization (FISH) remains largely unaddressed.

Methods

BCR-ABL1 signal patterns were analyzed using FISH in 243 CML-chronic phase (CML-CP), 17 CML-blast phase (CML-BP) and 52 BCR-ABL1 positive acute lymphoblastic leukemia (ALL) patients.

Results

The patterns of BCR-ABL1 signals presented complexity and diversity. A total of 12 BCR-ABL1 signals were observed in this cohort, including 1R1G2F, 1R1G1F, 2R1G1F, 1R2G1F, 2R2G1F, 1R2G2F, 1R1G3F, 1G3F, 2G3F, 1G4F, 1R1G4F and 1R4F. Complex BCR-ABL1 signal patterns (≥ two types of signal patterns) were observed in 52.9% (n = 9) of the CML-BP patients, followed by 30.8% (n = 16) of the ALL patients and only 2.1% (n = 5) of the CML-CP patients. More importantly, five clonal evolution patterns related to disease progression and relapse were observed, and patients with complex BCR-ABL1 signal patterns had a poorer overall survival (OS) time compared with those with single patterns (5.0 vs.15.0 months, p = 0.006).

Conclusions

Our data showed that complex BCR-ABL1 signal patterns were associated with leukemic clonal evolution and poorer prognosis in BCR-ABL1 positive leukemia. Monitoring BCR-ABL1 signal patterns might be an effective means to provide prognostic guidance and treatment choices for these patients.

SIGNIFICANCE OF ADDITIONAL CHROMOSOMAL ABNORMALITIES FOR THE OUTCOMES AFTER THE SECOND LINE NILOTINIB THERAPY IN THE CHRONIC MYELOID LEUKEMIA PATIENTS

Background. There is limited information about impact of additional chromosome aberrations (ACA) on the efficacy of the 2nd line nilotinib therapy. Objective. The aim of the study was to analyze significance of ACAs for the outcome after second line tyrosine kinase inhibitors (TKI) therapy with nilotinib in the chronic myeloid leukemia (CML) patients, who experienced previous imatinib therapy failure. Methods. The CML patients in chronic phase treated with nilotinib after imatinib failure were analyzed for outcomes. Results. Among a total of 114 patients, 18 patients (15.8%) had ACAs at the beginning of the 2nd line therapy with nilotinib. Seven patients (38.9%) of 18 had variant translocations and 11 patients (61.1%) had other chromosomal abnormalities in addition to t(9;22), known as clonal evolution. Complete cytogenetic response (CCR) at 12 months was achieved in 37.5%, 42.8% and 45.5% (p=0.842) of patients with classic t(9;22) translocation, variant translocations and ACAs respectively. In the patients with variant translocations t(9;V;22) or clonal evolution treated with nilotinib after the imatinib failure, the CCR and major molecular response (MMR), event free survival (EFS), progression free survival (PFS) and overall survival (OS) rates did not differ from those in the CML patients with t(9;22) only. At the same time quantitative characteristics of leukemic and ACA clones had prognostic value for CCR. The increased number of Ph-positive cells and the number of cells with the ACA at the start of nilotinib therapy reduced the probability of CCR. Conclusions. Higher nilotinib inhibitory activity compare with imatinib allows us to overcome imatinib resistance in the CML patients regardless of the ACA presence at the beginning of nilotinib therapy.

[Pre-therapeutic and evolutive characteristics of patients suffering from chronic myeloid leukemia, in Abidjan, Ivory Coast]

INTRODUCTION

The diagnosis of chronic myeloid leukemia is based on the presence of translocation t(9,22). Additional cytogenetic abnormalities may exist at diagnosis and have prognostic value. The authors evaluated the relationship between these additional chromosomal abnormalities, clinical presentation, and therapeutic response.

METHOD

In a retrospective and comparative study from 2005 to 2015, at Yopougon university hospital, 51 cases of myeloid leukemia were selected, including 22 cases with additional chromosomal abnormalities.

RESULTS

Thirteen types of additional Ph1 abnormalities were detected in one group, with a median age of 39years (13-73); a sex ratio of 1.4 and a low social class (49%). The median consultation time is 13months (2-29). Hepatomegaly (54%, P=0.05); fever (81.8%, P=0.0017); bone pain (63.6%, P=0.0001); lymphadenopathies (27.3% P=0.014); poor general condition [WHO>1 (77.3%, P=0.001)], high Sokal index (63.6%, P=0.0019), eosinophilia>5% (72.7, P=0.02) and circulating blastosis were found more frequent in the group with additional abnormalities treated with imatinib mesylate. We obtained 13.6% hematologic remission and 22.7% cytogenetic remission (P=0.02). The average survival was relatively short (20months vs. 76.4months, Log-rank<0.0001). We deplored a high death rate (59.1%).

CONCLUSION

The presence of an additional anomaly constitutes a pejorative element refractory to imatinib.

Impact of Additional Chromosomal Aberrations on the Disease Progression of Chronic Myelogenous Leukemia

The emergence of additional chromosomal abnormalities (ACAs) in Philadelphia chromosome/BCR-ABL1 positive chronic myeloid leukemia (CML), is considered to be a feature of disease evolution. However, their frequency of incidence, impact on prognosis and treatment response effect in CML is not conclusive. In the present study, we performed a chromosome analysis of 489 patients in different clinical stages of CML, using conventional GTG-banding, Fluorescent in situ Hybridization and Spectral Karyotyping. Among the de novo CP cases, ACAs were observed in 30 patients (10.20%) with lowest incidence, followed by IM resistant CP (16.66%) whereas in AP and BC, the occurrence of ACAs were higher, and was about 40.63 and 50.98%, respectively. The frequency of occurrence of ACAs were compared between the study groups and it was found that the incidence of ACAs was higher in BC compared to de novo and IM resistant CP cases. Likewise, it was higher in AP patients when compared between de novo and IM resistant CP cases, mirroring the fact of cytogenetic evolution with disease progression in CML. In addition, we observed 10 novel and 10 rare chromosomal aberrations among the study subjects. This study pinpoints the fact that the genome of advanced phase patients was highly unstable, and this environment of genomic instability is responsible for the high occurrence of ACAs. Treatment response analysis revealed that compared to initial phases, ACAs were associated with an adverse prognostic effect during the progressive stages of CML. This study further portrayed the cytogenetic mechanism of disease evolution in CML.

Comparative analysis of the Sokal, Euro and European Treatment and Outcome Study score in prognostication of Indian chronic myeloid leukemia-chronic phase patients on imatinib

Introduction:

The ultimate goal for CML management is risk stratification of the patients to design the appropriate treatment approach. The Sokal, Euro and EUTOS risk scores were established to prognosticate the patients on therapy.

Aim:

To perform a comparative assessment of the Sokal, Euro and EUTOS prognostic score in Indian CML-CP patients on imatinib.

Methods:

This is a retrospective study performed in 260 Ph+ CML-CP patients who were administered oral imatinib (400 mg/day).

Results:

166/260 were males and 94/260 were females (M: F::1.6:1) with median age 35 years (range 20-70). 92 (35.38%), 125 (48.07%) and 43 (16.5%) patients were divided into low, intermediate and high risk Sokal score respectively. 102 (39.23%), 106 (40.76%) and 52 (20%) patients were discriminated into low, intermediate and high risk Euro score respectively. 210 (80.7%) and 50 (19.2%) patients were divided into low and high risk EUTOS score. Cumulative incidence of MMR for low, intermediate and high-risk Sokal score was 87%, 76% and 84% respectively (P = 0.016). Incidence of MMR in low, intermediate and high-risk Euro score was 93%, 85% and 68% respectively (P = 0.001). Incidence of MMR was 80 % and 81% for low and high risk EUTOS score (P = 0.764). Both EFS and OS are significantly correlated with Sokal score (P = 0.004, P = 0.007) and Euro score (P = 0.009, P = 0.001) but not with EUTOS score (P = 0.581, P = 0.927).

Conclusion:

The present study highlights the significant prognostic role of Sokal and Euro score in predicting the treatment outcome of the CML- CP patients on imatinib.

Chronic myeloid leukemia with complex karyotypes: Prognosis and therapeutic approaches

OBJECTIVE AND BACKGROUND

Chronic myeloid leukemia (CML) is a neoplastic disease whose genetic and cytogenetic changes play important roles in prognosis and treatment strategies. Philadelphia (Ph) translocation t(9;22)(q34;q11) is a diagnostic and prognostic biomarker in CML.

METHODS

Pubmed and Google Scholar databases were searched for English language articles from 1975 to 2017 containing the terms CML; Additional chromosomal abnormalities; Philadelphia translocation; Prognosis; and Treatment.

DISCUSSION

Approximately 10-12% of CML patients exhibit additional chromosomal aberrations (ACAs) in chronic phase and blast crisis. ACAs emergence may cause different features in CML patients according to Ph pattern. For instance, deletion of chromosome 9 derivation is associated to patient's bad survival, whereas monosomy 7 develops myeloid dysplastic syndrome (MDS) or acute myeloid leukemia (AML) in CML patients with Ph-negative pattern. And ACAs in Ph-positive CML is considered as a failure in the management of CML with imatinib.

CONCLUSION

CML classification using different features such as Ph and ACAs can play a decisive role in the evaluation of treatment responses in patients, for example, CML patients with Ph negative and monosomy 7 develop MDS or CML patient -Y and extra copy of Ph have a good response to tyrosine kinase inhibitors, therefore, classifications according to Ph and ACAs play an important role in choosing better treatment protocols and therapeutic strategies. Karyotype analysis in CML patients with complex karyotype shows unrandom pattern so ACAs can be great clue in medical guidelines.

Recurrent chronic myeloid leukemia with t (9;22;16) (q34; q11; p13) treated by nilotinib: A case report

RATIONALE

Variant Philadelphia chromosome translocations involving chromosomes other than chromosomes 9 and 22 have been reported in 5% to 10% of patients with chronic myeloid leukemia (CML). Here, a case of CML with a t (9, 22, 16) (q34; q11; p13) translocation, which has never been described, is reported.

PATIENT CONCERNS

A 59-year-old female with dry cough, referred to our hospital, exhibited hepatosplenomegaly, high basophil count, and high platelet count at admission without any other known chronic diseases.

DIAGNOSES

The patient was diagnosed with CML with the translocation t (9;22;16) (q34; q11; p13). The patient was treated with imatinib, a first-generation tyrosine kinase inhibitor (TKI), discontinuously, achieving a complete hematological response for 7 years. Since November 8, 2017, the patient had recurrent fever, and her platelet count rose to 1422 × 10/L. Subsequently, the E279K mutation in the BCR-ABL kinase region was detected.

OUTCOMES

According to a previous report, this mutation confers sensitivity to nilotinib, a second-generation TKI. In the end, the patient received treatment with nilotinib and showed a complete hematological response.

LESSONS

The present study reports a rare case of CML with Ph chromosome and a t (9;22;16) (q34; q11; p13) translocation. For such cases about CML with variant Philadelphia chromosome translocations or BCR-ABL kinase region mutation, TKI may still be valuable.

Additional cytogenetic aberrations in chronic myeloid leukemia: a single-center experience in the Middle East

Background

Additional cytogenetic aberrations are associated with disease progression in chronic myeloid leukemia (CML). This study was conducted to determine the type and frequency of these aberrations and their relationship with hematologic and molecular findings in the Middle East.

Methods

In this retrospective study, 134 well-established cases of CML were selected from 2010 to 2016. Their hematologic phase and type of fusion gene were determined. Finally, their karyotypes were analyzed and reported according to ISCN 2013.

Results

Patients had a mean age of 44 years. Twenty-two patients (16.4%) showed additional cytogenetic aberrations. Nine patients (6.7%) harbored a variant Philadelphia chromosome, and most were in the chronic phase. Seventeen patients (12.7%) had major and minor route abnormalities. There was a significant relationship between additional cytogenetic aberrations and major molecular response (P=0.032). Patient survival in the group with additional cytogenetic aberrations was significantly lower (49.7±11.1 mo) than that in the group without additional cytogenetic aberrations (77.3±3.1 mo) (P=0.031).

Conclusion

This study revealed the same frequency of additional cytogenetic aberrations in CML as found in previous studies. Additional chromosomal aberrations led to shorter survival and lower rates of achievement of a major molecular response.

Cryptic BCR-ABL fusion gene as variant rearrangement in chronic myeloid leukemia: molecular cytogenetic characterization and influence on TKIs therapy

At diagnosis, about 5% of Chronic Myeloid Leukemia (CML) patients lacks Philadelphia chromosome (Ph), despite the presence of the BCR/ABL rearrangement. Two mechanisms have been proposed about the occurrence of this rearrangement: the first one is a cryptic insertion between chromosomes 9 and 22; the second one involves two sequential translocations: a classic t(9;22) followed by a reverse translocation, which reconstitutes the normal morphology of the partner chromosomes. Out of 398 newly diagnosed CML patients, we selected 12 Ph-negative cases. Six Ph-negative patients treated with tyrosine kinase inhibitors (TKIs) were characterized, in order to study the mechanisms leading to the rearrangement and the eventual correlation with prognosis in treatment with TKIs. FISH analysis revealed cryptic insertion in 5 patients and classic translocation in the last one. In more detail, we observed 4 different patterns of rearrangement, suggesting high genetic heterogeneity of these patients. In our cases, the BCR/ABL rearrangement mapped more frequently on 9q34 region than on 22q11 region, in contrast to previous reports. Four patients, with low Sokal risk, achieved Complete Cytogenetic Response and/or Major Molecular Response after TKIs therapy. Therapy resistance was observed in one patient with duplication of BCR/ABL rearrangement and in another one with high risk. Even if the number patient is inevitably low, we can confirm that the rare Ph-negative CML patients do not constitute a “warning” category, meanwhile the presence of further cytogenetic abnormalities remains an adverse prognostic factor even in TKI era.

Emerging alternatives to tyrosine kinase inhibitors for treating chronic myeloid leukemia

INTRODUCTION

BCR-ABL-directed tyrosine kinase inhibitors (TKIs) have revolutionised therapy for chronic myeloid leukemia. However, despite the availability and efficacy of this class of agents, lifelong treatment is still required in a significant proportion of patients Areas covered: We give an overview of the currently available BCR-ABL-directed TKIs and other conventional therapies for CML. We proceed to review the current market and some of the scientific rationale for new drug development before outlining a number of novel therapies, considered broadly as immunotherapies and targeted agents. Published English-language literature was reviewed regarding currently available TKIs; clinical trials repositories were reviewed to identify novel agents recently investigated or under active study. Expert opinion: We recommend discussion with patients and enrolment on an appropriate clinical trial where feasible. In situations where no trials are available, or if patients decline enrolment, we recommend use of an appropriate BCR-ABL directed TKI, selected on the basis of an evaluation of patient risk factors and side effect profile. Allogeneic stem cell transplant continues to have a role though this is generally limited to cases with advanced phases of disease or in cases with resistance-conferring mutations.

Therapeutic effects of tyrosine kinase inhibitors and subtypes of BCR-ABL1 transcripts in Japanese chronic myeloid leukemia patients with three-way chromosomal translocations

We analyzed the clinical responses to thyrosine kinase inhibitors (TKIs) and the molecular and cytogenetic characteristics of 18 chronic myeloid leukemia (CML) patients with 3-way chromosomal translocations. The patients were 14 men and 4 women, aged 23-75 years (median 57 years). The Sokal risk was low in 12 patients, intermediate in 4 patients, and high in 2 patients. Newly identified translocation breakpoints were seen in 7 of the 18 patients. Three patients had the same breakpoints of t(9;22;11)(q34;q11.2;q23). The best responses to TKIs were partial cytogenic response (PCyR) in 2 patients, complete cytogenic response (CCyR) in 3 patients, molecular response (MR) 3.0 in 7 patients, MR 4.0 in 3 patients, and MR 4.5 or higher in 3 patients. A total of 66.7% of patients did not achieve MR 4.0 or higher. In 3 patients in whom TKIs resulted in MR 4.5 or higher for more than 2 years, TKI treatment was discontinued. However, all of them exhibited a loss of MR3.0, at 2, 6, and 20 months after the discontinuation of treatment, respectively, and TKI treatment needed to be restarted. According to Kaplan-Meier survival curve analysis, the overall survival (OS) was 100 months in 56% of the patients. The 60-months cumulative incidences of CCyR, MR3.0, MR4.0 and MR4.5 were 88.9%, 72.2%, 33.3%, and 16.7%, respectively. In the 11 analyzable patients, the BCR-ABL1 mRNA subtype was e14a2 type in 4 patients and e13a2 type in 7 patients.

Prognostic significance of additional chromosomal abnormalities at the time of diagnosis in patients with chronic myeloid leukemia treated with frontline tyrosine kinase inhibitors

Additional cytogenetic abnormalities (ACA) are considered a high risk feature in chronic myeloid leukemia (CML). However, its prognostic significance at the time of diagnosis in the setting of new tyrosine kinase inhibitors (TKIs) is less well understood. Patients with CML in CP with or without ACA at diagnosis treated with frontline TKIs in prospective clinical trials were analyzed for outcomes. Among 603 patients treated, 29 (5%) had ACA. Patients with ACA included 2 of 72 (2.8%) treated with imatinib 400 mg, 9 of 207 (4.3%) with imatinib 800 mg, 10 of 148 (6.7%) with dasatinib, 6 of 126 (4.7%) with nilotinib, and 2 of 50 (4%) with ponatinib. There was a significantly higher rate of complete cytogenetic response (CCyR) at 6 months in patients without ACA (P = .02). However cumulative CCyR and major molecular response (MMR) rates were not different. Similarly, MR4.0 and MR4.5 rates were similar for both groups; two CML-ACA patients maintained MR 4.5 for at least 2 years. At 5 years, ACA at diagnosis did not significantly impact transformation-free, failure-free, event-free, or overall survival expectations. Acknowledging small sample size estimates, response rates and survival outcomes were comparable in CP with ACA irrespective of whether chromosomal abnormalities were "major route" or other. The presence of ACA at diagnosis does not confer worse prognosis for patients with CML treated with TKI. Thus, the presence of ACA at diagnosis should not alter treatment strategies in these patients.

Cytogenetics-based risk prediction of blastic transformation of chronic myeloid leukemia in the era of TKI therapy

The high fatality of patients with blast phase (BP) chronic myeloid leukemia (CML) necessitates identification of high-risk (HR) patients to prevent onset of BP. Here, we investigated the risk of BP based on additional chromosomal abnormality (ACA) profiles in a cohort of 2326 CML patients treated with tyrosine kinase inhibitors (TKIs). We examined the time intervals from initial diagnosis to ACA emergence (interval 1), from ACA emergence to onset of BP (interval 2), and survival after onset of BP (interval 3). Based on BP risk associated with each ACA, patients were stratified into intermediate-1, intermediate-2, and HR groups, with a median duration of interval 2 of unreached, 19.2 months, and 1.9 months, respectively. There was no difference in durations of intervals 1 or 3 among 3 groups. Including patients without ACAs who formed the standard-risk group, the overall 5-year cumulative probability of BP was 9.8%, 28.0%, 41.7%, and 67.4% for these 4 groups, respectively. The pre-BP disease course in those who developed BP was similar regardless of cytogenetic alterations, and 84.4% of BP patients developed BP within the first 5 years of diagnosis. In summary, interval 2 is the predominant determinant of BP risk and patient outcome. By prolonging the duration of interval 2, TKI therapy mitigates BP risk associated with low-risk ACAs or no ACAs but does not alter the natural course of CML with HR ACAs. Thus, we have identified a group of patients who have HR of BP and may benefit from timely alternative treatment to prevent onset of BP.

Dasatinib and Azacitidine Followed by Haploidentical Stem Cell Transplant for Chronic Myeloid Leukemia with Evolving Myelodysplasia: A Case Report and Review of Treatment Options

BACKGROUND CML presenting with a variant Philadelphia translocation, atypical BCR-ABL transcript, additional chromosomal aberrations, and evolving MDS is uncommon and therapeutically challenging. The prognostic significance of these genetic findings is uncertain, even as singular aberrations, with nearly no data on management and outcome when they coexist. MDS evolving during the course of CML may be either treatment-associated or an independently coexisting disease, and is generally considered to have an inferior prognosis. Tyrosine kinase inhibitors (TKI) directed against BCR-ABL are the mainstay of treatment for CML, whereas treatment modalities that may be utilized for MDS and CML include allogeneic stem cell transplant and - at least conceptually - hypomethylating agents. CASE REPORT Here, we describe the clinical course of such a patient, demonstrating that long-term combined treatment with dasatinib and azacitidine for coexisting CML and MDS is feasible and well tolerated, and may be capable of slowing disease progression. This combination therapy had no deleterious effect on subsequent potentially curative haploidentical bone marrow transplantation. CONCLUSIONS The different prognostic implications of this unusual case and new therapeutic options in CML are discussed, together with a review of the current literature on CML presenting with different types of genomic aberrations and the coincident development of MDS. Additionally, this case gives an example of long-term combined treatment of tyrosine kinase inhibitors and hypomethylating agents, which could be pioneering in CML treatment.

Moderate anemia at diagnosis is an independent prognostic marker of the EUTOS, Sokal, and Hasford scores for survival and treatment response in chronic-phase, chronic myeloid leukemia patients with frontline imatinib

OBJECTIVES

This study aimed to examine the prognostic value of anemia for the diagnosis of chronic myeloid leukemia in the chronic phase (CML-CP) receiving imatinib.

METHODS

One hundred and fifty-four CML-CP patients were enrolled. The influences of moderate anemia with hemoglobin (Hb) < 10 g/dl, four scoring systems, and the early molecular response at 3 months (BCR-ABL ≤10%; 3M-EMR) on the achievement of a deep molecular response (DMR, MR4.5), progression-free survival (PFS), event-free survival (EFS), and overall survival (OS) were compared.

RESULTS

Moderate anemia was identified in 44 (28.6%) patients. These patients had more aggressive baseline features and higher risks, as assessed by scoring systems, and less favorable treatment responses vs those without anemia, including 3M-EMR (50.0% vs 69.1%), a complete cytogenetic response at 6 months (20.5% vs 50.9%), and a major molecular response at 12 months (22.5% vs 45.2%), with a median follow-up of 54.0 months. Furthermore, an Hb of 10 g/dl better distinguished DMR, EFS, PFS, and OS than the EUTOS, Sokal, and Hasford scores, and better predicted the responses and survivals in combination with 3M-EMR than 3M-EMR alone.

CONCLUSIONS

This finding highlights the significance of anemia in CML-CP, and suggests that patients with anemia at diagnosis should be carefully monitored and might benefit from more potent TKIs if not achieving 3M-EMR.

Epigenetic dysregulation in chronic myeloid leukaemia: A myriad of mechanisms and therapeutic options

The onset of global epigenetic changes in chromatin that drive tumor proliferation and heterogeneity is a hallmark of many forms of cancer. Identifying the epigenetic mechanisms that govern these changes and developing therapeutic approaches to modulate them, is a well-established avenue pursued in translational cancer medicine. Chronic myeloid leukemia (CML) arises clonally when a hematopoietic stem cell (HSC) acquires the capacity to produce the constitutively active tyrosine kinase BCR-ABL1 fusion protein which drives tumor development. Treatment with tyrosine kinase inhibitors (TKI) that target BCR-ABL1 has been transformative in CML management but it does not lead to cure in the vast majority of patients. Thus novel therapeutic approaches are required and these must target changes to biological pathways that are aberrant in CML - including those that occur when epigenetic mechanisms are altered. These changes may be due to alterations in DNA or histones, their biochemical modifications and requisite 'writer' proteins, or to dysregulation of various types of non-coding RNAs that collectively function as modulators of transcriptional control and DNA integrity. Here, we review the evidence for subverted epigenetic mechanisms in CML and how these impact on a diverse set of biological pathways, on disease progression, prognosis and drug resistance. We will also discuss recent progress towards developing epigenetic therapies that show promise to improve CML patient care and may lead to improved cure rates.

Onset of chronic myeloid leukemia with complex karyotype in a pregnant patient: case report and revision of literature

Approximately 10%–12% of patients in chronic-phase chronic myeloid leukemia (CP-CML) have additional chromosomal aberrations at diagnosis; moreover, CML occurs in up to 10% of pregnancy-associated leukemias, with an annual incidence of 1 per 100,000 pregnancies. In this report we describe the case of a 36-year-old female with CP-CML diagnosed in the 18th week of pregnancy and with a new complex variant translocation t(4;9;22;21)(q24;q34;q11;q22) and an additional chromosomal aberration t(1;20)(p36;p11). In consideration of her pregnancy, the patient strictly monitored her blood cell count without any specific treatment. At 32 weeks of pregnancy, the patient delivered via cesarean section a healthy baby girl. After 10 days from childbirth, dasatinib was started at a standard dosage of 100 mg/day and 3 months later complete cytogenetic response and major molecular response were obtained, with the achievement of an optimal response according to European Leukemia Net recommendations and showing efficacy of this tyrosine kinase inhibitor (TKI) in the presence of a complex karyotype.

An unusual translocation, t(1;11)(q21;q23), in a case of chronic myeloid leukemia with a cryptic Philadelphia chromosome

Chronic myeloid leukemia (CML) is characterized by the translocation t(9;22)(q34;q11) [Philadelphia (Ph) chromosome). Although not frequently occurring, additional chromosome abnormalities (ACAs) can be detected at diagnosis and a number have been associated with an adverse cytogenetic and molecular outcome. The present study reports a case of CML presenting with the translocation t(1;11)(q21;q23) and a cryptic Ph chromosome. The presence of ACAs could generate greater genetic instability, promoting the emergence of further alterations. The present findings suggest that t(1;11)(q21;q23) can prevent a good response to tyrosine kinase inhibitor (TKI) therapy developing a primary resistance. In the present patient, at a recent follow-up, the T315I mutation was detected. This mutation confers full resistance to all available TKI, except ponatinib, which was not a therapeutic option due to comorbidities.

Additional cytogenetic abnormalities and variant t(9;22) at the diagnosis of childhood chronic myeloid leukemia: The experience of the International Registry for Chronic Myeloid Leukemia in Children and Adolescents

BACKGROUND

In the adult population with newly diagnosed chronic myeloid leukemia (CML), variant translocations are usually not considered to be impairing the prognosis, whereas some additional cytogenetic abnormalities (ACAs) are associated with a negative impact on survival. Because of the rarity of CML in the pediatric population, such abnormalities have not been investigated in a large group of children with CML.

METHODS

The prognostic relevance of variant t(9;22) and ACAs at diagnosis was assessed in 301 children with CML in the chronic phase who were enrolled in the International Registry for Chronic Myeloid Leukemia in Children and Adolescents.

RESULTS

Overall, 19 children (6.3%) presented with additional cytogenetic findings at diagnosis: 5 children (1.7%) had a variant t(9;22) translocation, 13 children (4.3%) had ACAs, and 1 had both. At 3 years, for children with a classic translocation, children with ACAs, and children with a variant t(9;22) translocation who were treated with imatinib as frontline therapy, the probability of progression-free survival (PFS) was 95% (95% confidence interval [CI], 91%-97%), 100%, and 75% (95% CI, 13%-96%), respectively, and the probability of overall survival (OS) was 98% (95% CI, 95%-100%), 100% (95% CI, 43%-98%), and 75% (95% CI, 13%-96%), respectively. No statistical difference was observed between the patients with classic cytogenetic findings and those with additional chromosomal abnormalities in terms of PFS and OS.

CONCLUSIONS

In contrast to adults with CML, additional chromosomal abnormalities observed at diagnosis do not seem to have a significant prognostic impact. Cancer 2017;123:3609-16. © 2017 American Cancer Society.

[Clinical significance of cytogenetic monitoring in chronic myeloid leukemia]

Objective: To analyze the association of cytogenetic abnormalities with the prognosis of chronic myeloid leukemia (CML) patients in tyrosine kinase inhibitors (TKI) era. Methods: Karyotype analysis of chromosome G-banding was carried out in 387 newly diagnosed CML patients by short-term culture of bone marrow cells. The correlation of cytogenetic abnormalities and CML progression was explored in combination with ABL tyrosine point mutations. Result: Of 387 patients with positive BCR-ABL fusion gene assayed by fluorescence in situ hybridization (FISH) technique, 94.1% (364/387) patients were Ph positive and 5.9% (23/387) Ph negative; 320 patients (87.9%) had a translocation t (9;22) (q34;q11) and 5 (1.4%) a variant translocation t (v;22) . Additional cytogenetic aberrations (ACA) at diagnosis were found in 10.7% (39/387) Ph(+) patients, major route ACA in 22 (56.4%) cases and minor route ACA in 15 (38.5%) cases and 2 patients (5.1%) lacked the Y chromosome (-Y) ; 23.4% (71/303) patients occurred ACA during TKI treatment and the most frequent abnormalities were abnormal chromosome numbersd, which were likely associated with high proportion of disease progression (χ(2)=168.21, P<0.001) and ABL tyrosine point mutations (χ(2)=29.04, P<0.001) . Newly diagnosed CML-CP patients with t (9;22) (q34;q11) had a longer event-free survival (EFS) and disease-free survival (DFS) rates than that of patients with ACA (P=0.037; P=0.003) , while the overall survival (OS) had no significant differences (P=0.209) . As for CML-CP patients that occurred ACA during TKI therapy would have a marked low OS, EFS and DFS (all P<0.001) compared with no ACA occurred patients. Survival of advanced patients that occurred ACA were dramatically reduced. Conclusion: ACA often emerged during the disease progress in CML patients, regular and timely detection of chromosomes karyotype and ABL tyrosine point mutations during TKI treatment was important for therapeutic evaluation, progress and prognosis of CML.