CRISPR-based rapid molecular diagnostic tests for fusion-driven leukemias.

ABSTRACT: Fusion oncogenes can be cancer-defining molecular alterations that are essential for diagnosis and therapy selection.1,2 Rapid and accessible molecular diagnostics for fusion-driven leukemias such as acute promyelocytic leukemia (APL), Philadelphia chromosome-positive acute lymphoblastic leukemia, and chronic myeloid leukemia (CML) are unavailable, creating a barrier to timely diagnosis and effective targeted therapy in many health care settings, including community hospitals and low-resource environments. We developed CRISPR-based RNA-fusion transcript detection assays using SHERLOCK (specific high-sensitivity enzymatic reporter unlocking) for the diagnosis of fusion-driven leukemias. We validated these assays using diagnostic samples from patients with APL and CML from academic centers and dried blood spots from low-resource environments, demonstrating 100% sensitivity and specificity. We identified assay optimizations to enable the use of these tests outside of tertiary cancer centers and clinical laboratories, enhancing the potential impact of this technology. Rapid point-of-care diagnostics can improve outcomes for patients with cancer by expanding access to therapies for highly treatable diseases that would otherwise lead to serious adverse outcomes due to delayed or missed diagnoses.

Lineage-specific detection of residual disease predicts relapse in patients with chronic myeloid leukemia stopping therapy.

ABSTRACT: Patients with chronic myeloid leukemia who are eligible for treatment-free remission (TFR) may still relapse after tyrosine kinase inhibitor (TKI) cessation. There is a need for accurate predictors of outcome to enable patients with a favorable profile to proceed while avoiding futile attempts. Sensitive detection of residual disease in total leukocytes at treatment cessation is associated with relapse but is not highly discriminatory, likely because it is a composite measure of residual leukemia derived from different cell lineages, whereas only some lineages are relevant for relapse. We prospectively measured BCR::ABL1 DNA as a predictive yes/no binary test in 5 cellular fractions from 48 patients meeting conventional criteria for TKI discontinuation. The median BCR::ABL1 DNA level was higher in granulocytes and T cells, but not in other lineages, in patients who relapsed. Among the 40 patients undergoing their first TFR attempt, we defined 3 groups with differing relapse risk: granulocyte-positive group (100%), granulocyte-negative/T-cell-positive group (67%), and granulocyte-negative /T-cell-negative group (25%). These data show the critical importance of lineage-specific assessment of residual disease in the selection of patients who can attempt to achieve TFR with a high expectation of success and, concurrently, defer patients who have a high probability of relapse.

Patient-reported symptom monitoring and adherence to therapy in patients with newly diagnosed chronic myeloid leukemia.

BACKGROUND: The authors assessed the clinical utility of patient-reported symptom monitoring in the setting of newly diagnosed chronic myeloid leukemia (CML). The primary objective was to evaluate adherence to therapy. METHODS: The authors conducted an international prospective study that included patients with newly diagnosed, chronic-phase CML. Before clinical consultation, patients were provided a tablet computer to self-rate their symptoms, and the results were available in real time to each physician during the patient's visit. Adherence was assessed by pill count and with a validated self-reported questionnaire. The proportions of optimal responders at 3 and 6 months were assessed according to the European LeukemiaNet criteria. RESULTS: Between July 2020 and August 2021, 94 patients with a median age of 57 years were enrolled. Pill count adherence analysis indicated that 86 of 93 evaluable patients (92.5%) took at least 90% of prescribed tyrosine kinase inhibitor therapy during the 6-month observation period. The online platform was well accepted by patients and physicians. An optimal response was achieved by 69 of 79 patients (87.3%) at 3 months and by 61 of 81 patients (75.3%) at 6 months. CONCLUSIONS: Patient-reported symptom monitoring from the beginning of therapy in patients with CML may be critical to improve adherence to therapy and early molecular response rates (ClinicalTrials.gov identifier NCT04384848).

Aleukemic Chronic Myeloid Leukemia Without Neutrophilia and Thrombocytosis: A Report From the BCR::ABL1 Pathology Group.

Chronic myeloid leukemia (CML) is characterized by leukocytosis with left-shifted neutrophilia, basophilia, eosinophilia, and variable thrombocytosis. However, extremely rare cases of patients with CML without significant leukocytosis and thrombocytosis (aleukemic phase [ALP] CML, or CML-ALP) have been reported. Due to its rarity and limited awareness, there remains a significant knowledge gap concerning the pathologic diagnosis, disease progression, and optimal patient management and outcomes. In this multi-institutional study, we investigated 31 patients with CML-ALP. Over half (54.8%) of patients had a history of or concurrent hematopoietic or nonhematopoietic malignancies. At time of diagnosis of CML-ALP, approximately 26.7% of patients exhibited neutrophilia, 56.7% had basophilia, and 13.3% showed eosinophilia. The median number of metaphases positive for t(9;22)(q34;q11.2) was 15, with a median of 38.5% of interphase nuclei positive for BCR::ABL1 by fluorescence in situ hybridization. The median BCR::ABL1 level was 26.14%. Remarkably, 14 (45.2%) patients were initially misdiagnosed or not diagnosed before karyotype or fluorescence in situ hybridization information for BCR::ABL1 became available. Twenty-five patients received tyrosine kinase inhibitors (TKIs). One patient developed blast crisis while on TKI treatment 8 months after initial diagnosis. With a median follow-up time of 46.1 months, 20 of 22 patients who received TKI therapy and had detailed follow-up information achieved complete cytogenetic remission or deeper, 15 achieved major molecular remission or deeper, and 10 achieved molecularly undetectable leukemia. In conclusion, given the frequent occurrence of prior or concurrent malignancies, aleukemic presentation, and low level of t(9;22)(q34;q11.2)/BCR::ABL1, misdiagnosis or delayed diagnosis is common among these patients. While these patients generally respond well to TKIs, rare patients may develop blastic transformation. It is therefore important for pathologists and hematologists to be aware of this highly unusual presentation of CML to ensure timely diagnosis and appropriate management.

The initial molecular response predicts the deep molecular response but not treatment-free remission maintenance in a real-world chronic myeloid leukemia cohort.

In chronic myeloid leukemia, the identification of early molecular predictors of stable treatment-free remission (TFR) after tyrosine kinase inhibitor (TKI) discontinuation is challenging. The predictive values of residual disease (BCR::ABL1 quantification) at month 3 and 6 and more recently, BCR::ABL1 transcript halving time (HT) have been described, but no study compared the predictive value of different early parameters. Using a real-world cohort of 408 patients, we compared the performance of the EUTOS long-term survival (ELTS) score, BCR::ABL1 HT, and residual disease at month 3 and 6 to predict the molecular response, achievement of the TKI discontinuation criteria, and TFR maintenance. The performances of BCR::ABL1 HT and residual disease at month 3 were similar. Residual disease at month 6 displayed the best performance for predicting the optimal response (area under the ROC curve between 0.81 and 0.92; cut-off values: 0.11% for MR4 at month 24 and 0.12% for MR4.5 at month 48). Conversely, no early parameter predicted reaching the TKI discontinuation criteria and TFR maintenance. We obtained similar results when patients were divided in subgroups by first-line treatment (imatinib vs. second-generation TKI [2G-TKI]). We identified a relationship between ELTS score, earlier milestones and TFR maintenance only in the 2G-TKI group. In conclusion, this first comparative study of early therapeutic response parameters showed that they are excellent indicators of TKI efficacy (BCR::ABL1 transcript reduction) and best responders. Conversely, they did not predict the achievement of the TKI discontinuation criteria and TFR maintenance, suggesting that other parameters are involved in TFR maintenance.

Application of artificial intelligence in chronic myeloid leukemia (CML) disease prediction and management: a scoping review.

BACKGROUND: Navigating the complexity of chronic myeloid leukemia (CML) diagnosis and management poses significant challenges, including the need for accurate prediction of disease progression and response to treatment. Artificial intelligence (AI) presents a transformative approach that enables the development of sophisticated predictive models and personalized treatment strategies that enhance early detection and improve therapeutic interventions for better patient outcomes. METHODS: An extensive search was conducted to retrieve relevant articles from PubMed, Scopus, and Web of Science databases up to April 24, 2023. Data were collected using a standardized extraction form, and the results are presented in tables and graphs, showing frequencies and percentages. The authors adhered to the PRISMA-ScR checklist to ensure transparent reporting of the study. RESULTS: Of the 176 articles initially identified, 12 were selected for our study after removing duplicates and applying the inclusion and exclusion criteria. AI's primary applications of AI in managing CML included tumor diagnosis/classification (n = 9, 75%), prediction/prognosis (n = 2, 17%), and treatment (n = 1, 8%). For tumor diagnosis, AI is categorized into blood smear image-based (n = 5), clinical parameter-based (n = 2), and gene profiling-based (n = 2) approaches. The most commonly employed AI models include Support Vector Machine (SVM) (n = 5), eXtreme Gradient Boosting (XGBoost) (n = 4), and various neural network methods, such as Artificial Neural Network (ANN) (n = 3). Furthermore, Hybrid Convolutional Neural Network with Interactive Autodidactic School (HCNN-IAS) achieved 100% accuracy and sensitivity in organizing leukemia data types, whereas MayGAN attained 99.8% accuracy and high performance in diagnosing CML from blood smear images. CONCLUSIONS: AI offers groundbreaking insights and tools for enhancing prediction, prognosis, and personalized treatment in chronic myeloid leukemia. Integrated AI systems empower healthcare practitioners with advanced analytics, optimizing patient care and improving clinical outcomes in CML management.

Hsa_circ_0006010 and hsa_circ_0002903 in peripheral blood serve as novel diagnostic, surveillance and prognostic biomarkers for disease progression in chronic myeloid leukemia.

BACKGROUND: In the era of tyrosine kinase inhibitor (TKI) treatment, the progression of chronic myeloid leukemia (CML) remains a significant clinical challenge, and genetic biomarkers for the early identification of CML patients at risk for progression are limited. This study explored whether essential circular RNAs (circRNAs) can be used as biomarkers for diagnosing and monitoring CML disease progression and assessing CML prognosis. METHODS: Peripheral blood (PB) samples were collected from 173 CML patients (138 patients with chronic phase CML [CML-CP] and 35 patients with accelerated phase/blast phase CML [CML-AP/BP]) and 63 healthy controls (HCs). High-throughput RNA sequencing (RNA-Seq) was used to screen dysregulated candidate circRNAs for a circRNA signature associated with CML disease progression. Quantitative real-time PCR (qRT-PCR) was used for preliminary verification and screening of candidate dysregulated genes, as well as subsequent exploration of clinical applications. Receiver operating characteristic (ROC) curve analysis, Spearman's rho correlation test, and the Kaplan-Meier method were used for statistical analysis. RESULTS: The aberrant expression of hsa_circ_0006010 and hsa_circ_0002903 during CML progression could serve as valuable biomarkers for differentiating CML-AP/BP patients from CMP-CP patients or HCs. In addition, the expression levels of hsa_circ_0006010 and hsa_circ_0002903 were significantly associated with the clinical features of CML patients but were not directly related to the four scoring systems. Furthermore, survival analysis revealed that high hsa_circ_0006010 expression and low hsa_circ_0002903 expression indicated poor progression-free survival (PFS) in CML patients. Finally, PB hsa_circ_0006010 and hsa_circ_0002903 expression at diagnosis may also serve as disease progression surveillance markers for CML patients but were not correlated with PB BCR-ABL1/ABL1IS. CONCLUSIONS: Our study demonstrated that PB levels of hsa_circ_0006010 and hsa_circ_0002903 may serve as novel diagnostic, surveillance, and prognostic biomarkers for CML disease progression and may contribute to assisting in the diagnosis of CML patients at risk for progression and accurate management of advanced CML patients.

Cytogenetic and epidemiological profile of chronic myeloid leukemia in Morocco.

Chronic myeloid leukemia (CML) is a neoplastic disease of genetic origin resulting from clonal proliferation of hematopoietic stem cells (HSCs). The reciprocal translocation t(9;22)(q34;q11) is the main chromosomal abnormality involved in this pathology, usually detected by conventional cytogenetics. This article aims to investigate the epidemiological, cytogenetic, therapeutic, and clinical characteristics of Moroccan patients with CML. This research represents the first large-scale study of CML patients in Morocco and was carried out at Institut Pasteur of Morocco. Bone marrow samples were processed for cytogenetic analysis, and karyotypes were described according to an international system of human cytogenetic nomenclature (ISCN 2016). Patients were studied according to their epidemiological characteristics, clinical information and cytogenetic results. For statistical calculations, R version 4.3.1 was used to analyze the data and calculate the statistical parameters. RStudio and Power BI were used for data visualization. The National Cancer Institute (NCI) Surveillance, Epidemiology, and End Results (SEER) method of incidence estimation was used to calculate our incidence. We received 826 patients (from 1992 to 2023) who were referred for suspected CML or who were undergoing treatment. Only 650 patients with confirmed CML were included in the study, all of whom underwent their first cytogenetic test. The median age of our patients was 45 years and the sex ratio was 1.03. At the time of diagnosis, 147 (30%) of the patients had clinical manifestations. Most patients were diagnosed in the chronic phase (94.5%). Nineteen complex variant translocations of the Philadelphia (Ph) chromosome were detected. At the time of diagnosis, 55 (11.5%) patients had ACAs, of which 30 (54.5%) were high-risk ACAs. Based on data from 174 patients treated with imatinib, the median time to complete cytogenetic response (CCyR) was 11 months, and at the last cytogenetic follow-up, 81 patients (46.6%) achieved CCyR, while 64 patients (36.8%) showed no response to treatment. Regarding adherence to European LeukemiaNet (ELN) guidelines, 58 patients (33%) were followed according to these guidelines, with optimal treatment in 8.6%, suboptimal treatment in 7% and treatment failure in 18%. The estimated incidence of chronic myeloid leukemia calculated is 0.6 cases per 100,000 in the Casablanca region. This study provides a detailed overview of CML in Morocco, highlighting important clinical, cytogenetic and therapeutic aspects despite some limitations. It also highlights the need to deepen our understanding of this complex disease for disease management in our specific context.

Beyond BCR::ABL1-The Role of Genomic Analyses in the Management of CML.

Chronic myeloid leukemia (CML) is a model of genomically based diagnosis and management where BCR::ABL1 is successfully targeted by tyrosine kinase inhibitor (TKI) therapy in most patients. The dynamics of BCR::ABL1 transcript decline during therapy is a dependable biomarker of response, relapse, and drug resistance. Missense mutations acquired within the BCR::ABL1 kinase domain that disrupt TKI binding can evolve during therapy and are frequently detected in patients for whom TKI treatment fails. Importantly, specific BCR::ABL1 missense mutations are targetable alterations and direct therapeutic decisions based on the individual mutant TKI sensitivity profile. Nevertheless, BCR::ABL1 mutations are only implicated in approximately half of the cases of acquired resistance. Furthermore, not all patients with a single BCR::ABL1 mutation that is predicted to be sensitive to a specific TKI will experience a response when switched to that TKI. Progression to blast phase heralds independence from BCR::ABL1, and this phase of the disease is notoriously difficult to treat. The independent drivers of resistance and disease progression have long been investigated to both predict progression and to find targets for therapeutic intervention. Recent data reaffirm that drug resistance and disease progression is a mutation-driven process in CML, and somatic variants in genes that are known to drive acute myeloid and lymphoid leukemia have been detected in patients in the advanced phases of CML. Genomic testing over the last few decades for patients with blood cancer has revealed of variety of genomic aberrations that drive disease. Consequently, incorporation of genomic factors into patient management for a range of blood cancers has led to the implementation of high-throughput gene testing to detect clinically actionable variants. Is it time to integrate broader genomic screening into clinical management strategies for patients with CML?

Chronic Myeloid Leukemia, Version 2.2024, NCCN Clinical Practice Guidelines in Oncology.

Chronic myeloid leukemia (CML) is defined by the presence of Philadelphia chromosome resulting from a reciprocal translocation between chromosomes 9 and 22 [t9;22] that gives rise to a BCR::ABL1 fusion gene. CML occurs in 3 different phases (chronic, accelerated, and blast phase) and is usually diagnosed in the chronic phase in developed countries. Tyrosine kinase inhibitor (TKI) therapy is a highly effective treatment option for patients with chronic phase-CML. The primary goal of TKI therapy in patients with chronic phase-CML is to prevent disease progression to accelerated phase-CML or blast phase-CML. Discontinuation of TKI therapy with careful monitoring is feasible in selected patients. This manuscript discusses the recommendations outlined in the NCCN Guidelines for the diagnosis and management of patients with chronic phase-CML.

Chronic myeloid leukemia (CML) in children and adolescents-Clinicopathological findings.

BACKGROUND: Barely two per million Belgian children/adolescents are diagnosed with chronic myeloid leukemia (CML) annually. In this retrospective study, we aimed to investigate the diagnostic features, clinical and laboratory characteristics, and treatment outcome of this rare entity. METHODS: Medical records of all pediatric CML patients (age ≤ 17 years) diagnosed at the University Hospitals Leuven between 1986 and 2021 were reviewed. RESULTS: Fourteen patients (median age at diagnosis 12.5 years) were included, all presenting in chronic phase. Five patients were diagnosed before 2003; main therapy included hydroxyurea (n = 5/5), interferon-alfa (n = 3/5) and allogeneic hematopoietic stem cell transplantation (allo-Tx) (n = 3/5). Complete hematologic response (CHR), complete cytogenetic response (CCyR) and major molecular response (MMR) was reached in resp. 4/5, 4/5 and in 2/3 of evaluable patients. Three patients progressed to accelerated/blast phase (median time 19 months) and 1/5 is alive and disease-free at last follow-up. Nine patients were diagnosed after 2003 and were treated with first generation (1°G) tyrosine kinase inhibitors (TKI): 3/9 subsequently underwent an allo-Tx, 4/9 were switched to 2°G TKI, one patient was additionally switched to 3°G TKI. CHR, CCyR and MMR was reached in 9/9, 9/9 and 8/9 of these patients. No progression to accelerated/blast phase was observed and none of these patients deceased. At last follow-up, 7/9 patients were in MMR or disease free, the two remaining patients did not reach or lost MMR, both related to compliance issues. CONCLUSION: Our study confirmed that TKI significantly improved the prognosis of pediatric CML. However, drug compliance poses a considerable challenge.

A Rare Case of X-Linked Four-Way Philadelphia Chromosome Translocation with Therapeutic Challenges and Clonal Evolution.

BACKGROUND: Chronic myeloid leukemia (CML), a myeloproliferative neoplasm defined by the BCR::ABL1 fusion gene arising from the Philadelphia chromosome (Ph) translocation t(9:22)(q34;q11), exhibits diverse clinical courses often influenced by additional chromosomal aberrations (ACAs). This report presents a case of CML har-boring a novel four-way Ph translocation involving the X chromosome, offering insights into the interplay between complex karyotypes and treatment response and emphasizing the need for further research into the role of ACAs in CML management. METHODS: A 42-year-old man diagnosed with CML in the accelerated phase presented a novel four-way Ph translocation involving chromosomes X, 5, 9, and 22: 46,Y,t(X;5;9;22)(q26;q15;q34;q11.2). Despite achieving a major molecular response initially with imatinib and nilotinib, BCR::ABL1 levels (international scale) increased up to 24.0%, which prompted the use of second-line nilotinib. RESULTS: Follow-up bone marrow (BM) studies revealed clonal evolution with trisomy 8 and an unclassified ABL1 mutation (E292V), potentially contributing to resistance. Though a transient major molecular response (MMR) occurred after a switch to third-line dasatinib, this change failed to achieve a deep molecular response, and BCR-ABL1 levels were elevated above the MMR. CONCLUSIONS: This case highlights the challenge of ACAs impacting CML treatment response and prognosis. Limited knowledge exists on complex Ph translocations involving the X chromosome, but this report contributes data for further research. Understanding ACA effects on therapeutic response and prognosis requires a detailed study of such complex chromosomal aberrations.

Prognostic Factors and Clinical Outcomes in Patients with Blast Phase Chronic Myeloid Leukemia.

BACKGROUND: Given the low incidence of patients with advanced chronic myeloid leukemia (CML), comprehensive clinical characteristics and outcomes of cohort studies of patients diagnosed with blast phase chronic myeloid leukemia (BP-CML) are limited. We examined the clinical features of blast phase CML, including the TKI selection, treatment response, and whether they have had hematopoietic stem cell transplantation (HSCT) or not. METHODS: We performed a retrospective cohort study, including BP-CML patients diagnosed in our center from January 2013 to December 2022. Clinical features, treatment therapy, and overall survival (OS) were investigated. RESULTS: Out of the 11 patients, 2 were myeloid type, eight patients were B-lymphoid, and one was T-lymphoid. Four patients suffered from chromosome abnormalities. Four patients were identified with BCR-ABL1 kinase domain mutation, including T315I, E255K, M244v, and E279K. The overall CR, CRi, PR, and MLFS rates were 9%, 54%, 27%, and 9%, respectively. The median follow-up was 21 months (9.5 - 33 months). At the end of the follow-up time, seven patients died. CML patients with lymphoids tended to get a better OS than patients with a type of myeloid, but the difference was not statistically significant (p > 0.05). Patients who received HSCT had an improved OS by two years compared to those who had not received HSCT. CONCLUSIONS: The prognosis of BP-CML patients was poor. Given the rarity of BP-CML and the limitation of clinical trial data, large-scale multi-center prospective studies are urgently needed to confirm and improve the treatment of patients with BP-CML in the future.

Challenges in Management of Pediatric Chronic Myeloid Leukemia (pCML) in the Low-Middle Income Countries (LMICs): Insights from an International CML Foundation (iCMLf) Multi-National Survey.

Despite being a rare disease, high-income countries (HICs) have formulated guidelines for management of pediatric CML (pCML). We conducted a survey amongst 24 physicians from 22 Low-Middle Income Countries (LMICs) to gather information regarding their practice and experience in treating children with pCML. Rarity of pCML, lack of adequate expertise, and setting-adapted guidelines along with limitations in diagnostic infrastructure as well as challenges in accessing tyrosine kinase inhibitors (TKIs) were identified as major barriers in optimum management of patients. For the first time in literature, our findings provide valuable insights into the multifaceted challenges faced in managing pCML in LMICs.

The Screening of microRNAs in Chronic Myeloid Leukemia: A Clinical Evaluation.

Chronic myeloid leukemia (CML) is a type of leukemia whose main genetic marker is the reciprocal translocation that leads to the production of the BCR::ABL1 oncoprotein. The expression of some genes may interfere with the progression and development of leukemias. MicroRNAs are small non-coding RNAs that have the potential to alter the expression of some genes and may be correlated with some types of leukemia and could be used as biomarkers in the diagnosis and prognosis of patients. Therefore, this project carried out an analysis of microRNA-type plasma biomarkers in patients with chronic myeloid leukemia at unique points, including follow-up analysis of patients from the Erasto Gaertner Hospital. 35 microRNAs were analyzed in different cohorts. Inside those groups, 70 samples were analyzed at unique points and 11 patients in a follow-up analysis. Statistically different results were found for microRNA-7-5p, which was found to be upregulated in patients with high expression of the BCR::ABL1 transcript when compared to healthy controls. This microRNA also had evidence of behavior related to BCR::ABL1 when analyzed in follow-up, but strong evidence was not found. In this way, this work obtained results that may lead to manifestations of a relationship between miR-7-5p and chronic myeloid leukemia, and evaluations of possible microRNAs that are not related to this pathology.

[Comparison of quantitative detection of BCR::ABL1 p210 transcript levels: a multicenter study].

Objective: To assess the capability of seven reference medical laboratories to detect BCR::ABL1 p210 transcription levels and to compare the results among those laboratories. Methods: The interlaboratory comparison was carried out in two stages. The samples were prepared by the reference laboratory. The quantitative values of BCR::ABL1 p210 of the comparison samples covered 0.001%-0.01%, 0.01%-0.1%, 0.1%-1%, 1%-10% and>10% in each stage. Real-time quantitative PCR (RT-PCR) and dPCR (digital PCR) were used to examine the samples. The conversion factor (CF) was calculated and validated for each laboratory. Results: In the RT-PCR comparison, one laboratory was failed to detect BCR::ABL1 p210 in fourteen samples at the first stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.133-0.338) and 95% limits of agreement within ±5 folds (upper limit 0.147-0.785, lower limit -0.770--0.109), and the corresponding CF values were calculated and validated. In the dPCR comparison, one laboratory did not report results at the second stage. The results of the other six laboratories were qualified with the bias <±1.2 folds (-0.026-0.267) and 95% limits of agreement within±5 folds (upper limit 0.084-0.991, lower limit -0.669--0.135), and the corresponding CF values were calculated and validated. The samples with BCR::ABL1 p210 quantitative values of 0.01%-0.1%, 0.1%-1%, 1%-10% and >10% could be detected by both RT-PCR and qPCR. When the quantitative value of BCR::ABL1 p210 was 0.001%-0.01%, the detection rate of dPCR was higher than that of RT-PCR (85.56% vs. 68.00%). Conclusions: A good consistency is present among various laboratories. The quantitative value of BCR::ABL1 p210 is comparable among laboratories as shown by the CF value conversion. For quantitative detection of BCR::ABL1 p210 deep molecular reaction, dPCR has a higher positive detection rate and more advantages than RT-PCR. To ensure the accuracy and reproducibility of the BCR::ABL1 p210 test, it is imperative for every laboratory to enhance their daily quality control practices.

[Recent findings and advances in treatment of chronic myeloid leukemia].

Imatinib, the first ABL-tyrosine kinase inhibitor (TKI), was approved in 2000 for the treatment of chronic myeloid leukemia (CML). Second- and third-generation TKIs, as well as asciminib, which targets a different site of BCR-ABL1 (the myristoyl pocket), were later approved in 2022. Currently, six drugs are approved for the treatment of CML. Revisions to the clinical guidelines for hematopoietic tumors in 2023 provided new guidance on the utility of new agents as well as TKI dose reduction and treatment discontinuation. This article outlines recently reported predictions regarding TKI treatment response, the role of asciminib in the treatment of CML, and development of new agents, as well as the latest findings regarding the current state of TKI treatment discontinuation.

Asymmetric Hairpins DNA Encapsulated Silver Nanoclusters for In Situ Fluorescence Imaging of Fusion Gene Isoforms in Bone Marrow.

Rapid and accurate imaging of the BCR/ABL fusion gene isoforms (e.g., e13a2, e14a2 and co-expression type) of chronic myeloid leukemia (CML) is of vital importance to first-line drug selection, but there is no assay that meets clinical needs (e.g., clinical kits > 18 h without isoforms information). Herein, an in situ imaging platform is developed for the rapid and accurate detection of CML fusion gene isoforms using asymmetric sequence-enhanced hairpins DNA encapsulated silver nanoclusters (ADHA) and catalyzed hairpin assembly (CHA). The specific detection of e13a2 and e14a2 fusion gene isoforms with detection limits of 19.2 am (11.558 copies µL-1 ) and 32.56 am (19.601 copies µL-1 ) in one-pot is achieved. The feasibility of the developed assay for real-world applications are demonstrated by one-step fluorescence imaging (40 min) of e13a2, e14a2 and co-expression type in bone marrow quantitatively (International Standard: 15.66%-168.878%) and further validated by cDNA-sequencing. This work suggests that the developed imaging platform holds great potential for rapid identification of the fusion gene isoforms and isoform related treatment monitoring.

Blast phase of chronic myeloid leukemia with concurrent BCR::ABL1 and SET::NUP214: A report of two cases.

Chronic myeloid leukemia (CML) is a myeloproliferative neoplasm defined by the presence of t(9;22)(q34;q11.2)/BCR::ABL1. Additional chromosomal abnormalities play an important role in the progression to CML. However, the additional fusion gene was rarely reported such as CBFB::MYH11. In this report, we described two cases of the co-occurrence of BCR::ABL1 and SET::NUP214 in CML-BP for the first time, which is associated with poor outcomes during tyrosine kinase inhibitor (TKI) treatment. Meanwhile, we retrospectively analyzed SET::NUP214 fusion transcript of the two cases at initial diagnosis of the CML chronic phase by quantitative RT-PCR, and detected at a ratio of 1.63% and 1.50%, respectively. SET::NUP214 may promote disease progression during the transformation of CML. This study highlights the importance of extended molecular testing at the initial diagnosis of CML-CP at TKI resistance and/or disease transformation.

The Diagnosis of Chronic Myeloid Leukemia with Deep Adversarial Learning.

Chronic myeloid leukemia (CML) is a clonal proliferative disorder of granulocytic lineage, with morphologic evaluation as the first step for a definite diagnosis. This study developed a conditional generative adversarial network (cGAN)-based model, CMLcGAN, to segment megakaryocytes from myeloid cells in bone marrow biopsies. After segmentation, the statistical characteristics of two types of cells were extracted and compared between patients and controls. At the segmentation phase, the CMLcGAN was evaluated on 517 images (512 × 512) which achieved a mean pixel accuracy of 95.1%, a mean intersection over union of 71.2%, and a mean Dice coefficient of 81.8%. In addition, the CMLcGAN was compared with seven other available deep learning-based segmentation models and achieved a better segmentation performance. At the clinical validation phase, a series of seven-dimensional statistical features from various cells were extracted. Using the t-test, five-dimensional features were selected as the clinical prediction feature set. Finally, the model iterated 100 times using threefold cross-validation on whole slide images (58 CML cases and 31 healthy cases), and the final best AUC was 84.93%. In conclusion, a CMLcGAN model was established for multiclass segmentation of bone marrow cells that performed better than other deep learning-based segmentation models.