Pediatric chronic myeloid leukemia (CML) is more aggressive than adult CML, with unique molecular characteristics and a higher propensity for lymphoid blast crisis. The application of tyrosine kinase inhibitors (TKIs) has significantly improved the prognosis of pediatric CML. Based on international consensus and clinical experience, this article proposes standardized diagnosis and treatment recommendations for pediatric CML, covering initial therapy selection, efficacy evaluation, drug switching, and management of adverse effects. Allogeneic hematopoietic stem cell transplantation (allo-HSCT) is recommended only for patients with disease progression or failure of multiple lines of TKI therapy. For children newly diagnosed with CML in accelerated phase, high-dose imatinib or second-generation TKIs are recommended as first-line therapy. Those achieving optimal responses should continue maintenance therapy, while non-responders require switching to alternative TKIs and consider allo-HSCT. For blast-phase CML, induction therapy requires a combination of TKIs and chemotherapy, with allo-HSCT serving as the core curative intervention. This article highlights common but challenging problems (poor response, drug intolerance, and disease progression) in pediatric CML treatment using three typical cases, aiming to optimize treatment strategies. Furthermore, the goal of achieving treatment-free remission needs to be further addressed through multi-center clinical studies.
Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Child ; Hematopoietic Stem Cell Transplantation ; Protein Kinase Inhibitors/therapeutic use* ; Male ; Female ; Adolescent

OBJECTIVE: To screen the genetic risk factors related to severe hematology adverse effects (AEs) in patients with chronic myeloid leukemia (CML) treated with imatinib (IM), and explore the correlation of single nucleotide polymorphisms (SNPs) in IM drug metabolism and transport pathway gene polymorphism with the risk of severe hematology AEs. METHODS: 172 newly diagnosed Chinese Han patients in CML chronic phase (CML-CP) treated with IM were included and divided into severe hematology AEs group and non-severe hematology AEs group. The demographic characteristics and laboratory test results were compared between the two groups. 11 gene SNP sites in the included subjects were genotyped using SNaPshot multiplex SNPs technique. RESULTS: Compared with non-severe hematology AEs group, the severe hematology AEs group had higher white blood cell (WBC) and EOS% (both P < 0.05), but lower hemoglobin (Hb) and hematocrit (HCT) (both P < 0.01). For rs1045642 of ABCB1 gene, there were significant differences in the distribution of allele frequency and genotype frequency of this loci between severe hematology AEs group and non-severe hematology AEs group (both P < 0.05). Carriers of rs1045642 mutation allele A had an increased risk of severe hematology AEs (OR =2.09, 95% CI : 1.24-3.55, P =0.005). There was a significant difference in the distribution of NR1I2 gene rs3814055 genotype between severe hematology AEs group and non-severe hematology AEs group (P < 0.05). The additive model and recessive model of ABCB1 gene rs1045642 and the recessive model of NR1I2 gene rs3814055 were associated with the increased risk of severe hematology AEs (OR =2.14, 3.28, 5.54, all P < 0.05). CONCLUSION Peripheral blood WBC, EOS%, Hb and HCT in patients with newly diagnosed CML-CP are all related to the risk of severe hematology AEs. ABCB1 gene rs1045642 and NR1I2 gene rs3814055 related to the metabolism and transport pathway of IM are associated with severe hematology AEs after IM treatment in CML-CP patients, and they may be potential molecular markers to predict the risk of severe hematology AEs of CML patients treated by IM.
Humans ; Imatinib Mesylate ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics* ; Polymorphism, Single Nucleotide ; Genotype ; ATP Binding Cassette Transporter, Subfamily B ; Gene Frequency ; Female ; Male ; Middle Aged ; Adult ; Asian People

OBJECTIVE: To screen factors affecting the prognosis of chronic myeloid leukemia (CML) patients, and construct a nomogram model for event-free survival (EFS). METHODS: To screen out meaningful variables by univariate and multivariate Cox regression analysis in CML patients, and construct a nomogram model using R software. The nomogram was validated using consistency index (C-index), receiver operating characteristic (ROC) curve, area under the ROC curve (AUC), calibration curve, decision curve analysis (DCA), and risk stratification analysis. RESULTS: This study analyzed data from 116 CML patients. Univariate and multivariate Cox regression analysis demonstrated that age, peripheral blood basophil percentage, BCR-ABL1 ^IS at 3 months, and red blood cell distribution width (RDW) were independent prognostic factors of EFS. Subsequently, a nomogram was constructed based on the above predictors. The C-index of the nomogram was 0.733(95%CI : 0.676-0.790). The AUC values for predicting 1-, 3-, and 5-year EFS rate were 0.765, 0.855, and 0.827, respectively. The results of the calibration curve and DCA curve showed that the predictive model had good consistency, as well as strong clinical utility. The patients were stratified into high-risk group and low-risk group based on the total score of the model, there was a significant difference in EFS between the two groups (P < 0.001). CONCLUSION Age, peripheral blood basophil percentage, BCR-ABL1 ^IS at 3 months, and RDW were associated with the prognosis of CML patients. The nomogram model constructed in this study can accurately predict the prognostic status of CML patients, but its widespread application still requires external and prospective validation.
Nomograms ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/mortality* ; Proportional Hazards Models ; Erythrocyte Indices ; Risk Assessment/methods* ; Fusion Proteins, bcr-abl/genetics* ; Basophils ; Leukocyte Count ; Humans

OBJECTIVE: To investigate the effect of different previous treatments on the efficacy of flumatinib in patients with chronic myeloid leukemia (CML). METHODS: The clinical data of 69 patients with CML treated with flumatinib in the Affiliated Hospital of Xuzhou Medical University from 2019 to 2024 were retrospectively analyzed. The patients were divided into a first-line flumatinib group and a first-line non-flumatinib group according to whether flumatinib was used as first-line treatment. The molecular response (MR) at 3, 6 and 12 months of treatment was compared between the two groups to evaluate the early efficacy. The first-line non-flumatinib group was further divided into imatinib group, nilotinib group, and dasatinib group according to the previous first-line drugs used. The efficacy data of these three groups at 3, 6 and 12 months after switching to flumatinib were collected, and the MR was evaluated to compare efficacy differences. RESULTS: The rate of early molecular response (EMR) in the first-line flumatinib group was significantly higher than that in the first-line non-flumatinib group (P < 0.05). At 6 months and 12 months of treatment, the proportion of patients achieving MR 4.5 in the first-line flumatinib group was significantly higher than that in the first-line non-flumatinib group (P < 0.05). Compared with the imatinib and nilotinib groups, the previous dasatinib group showed a significantly higher proportion of patients achieving MR 5.0 at 3, 6, and 12 months after switching to flumatinib (P < 0.05). CONCLUSION Compared with the previous treatment with other tyrosine kinase inhibitors (TKIs), initial use of flumatinib at diagnosis enable patients to achieve deeper molecular remission more rapidly. Compared with previous use of imatinib or nilotinib, previous use of dasatinib is associated with deeper molecular remission after switching to flumatinib.
Humans ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Retrospective Studies ; Imatinib Mesylate/therapeutic use* ; Dasatinib/therapeutic use* ; Treatment Outcome ; Pyrimidines/therapeutic use* ; Female ; Male ; Protein Kinase Inhibitors/therapeutic use* ; Middle Aged ; Antineoplastic Agents/therapeutic use*

Chronic Myeloid Leukemia, a chronic hematopoietic stem cell disorder, is uncommon among younger age group such as pregnant patients. Due to the rarity of this condition in pregnancy, there are no randomized controlled trials to address the optimal management of this condition. We are presented with a 26 year old patient, who had an unplanned pregnancy in the advanced phase of the disease. Due to the risk to the mother in delaying treatment, she was continued on Imatinib, a tyrosine kinase inhibitor, which is a known fetal teratogen. Her pregnancy was carried to term. The patient delivered via spontaneous vaginal delivery to a live, neonate, with findings of hydrocele and syndactyly on the 4" and 5™ digit of the right foot. Due to the maternal disease progression, she presented with postpartum hemorrhage, in contrast to an augmented procoagulant state among normal pregnancies. Obstetric adjunctive measures, such as intrauterine balloon tamponade and uterine artery ligation, were done. The patient was discharged stable.
Leukemia, Myelogenous, Chronic, BCR-ABL Positive ; Imatinib Mesylate ; Postpartum Hemorrhage ; Pregnancy

Objective: To analyze and compare therapy responses, outcomes, and incidence of severe hematologic adverse events of flumatinib and imatinib in patients newly diagnosed with chronic phase chronic myeloid leukemia (CML) . Methods: Data of patients with chronic phase CML diagnosed between January 2006 and November 2022 from 76 centers, aged ≥18 years, and received initial flumatinib or imatinib therapy within 6 months after diagnosis in China were retrospectively interrogated. Propensity score matching (PSM) analysis was performed to reduce the bias of the initial TKI selection, and the therapy responses and outcomes of patients receiving initial flumatinib or imatinib therapy were compared. Results: A total of 4 833 adult patients with CML receiving initial imatinib (n=4 380) or flumatinib (n=453) therapy were included in the study. In the imatinib cohort, the median follow-up time was 54 [interquartile range (IQR), 31-85] months, and the 7-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.2%, 88.4%, 78.3%, and 63.0%, respectively. The 7-year FFS, PFS, and OS rates were 71.8%, 93.0%, and 96.9%, respectively. With the median follow-up of 18 (IQR, 13-25) months in the flumatinib cohort, the 2-year cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) were 95.4%, 86.5%, 58.4%, and 46.6%, respectively. The 2-year FFS, PFS, and OS rates were 80.1%, 95.0%, and 99.5%, respectively. The PSM analysis indicated that patients receiving initial flumatinib therapy had significantly higher cumulative incidences of CCyR, MMR, MR(4), and MR(4.5) and higher probabilities of FFS than those receiving the initial imatinib therapy (all P<0.001), whereas the PFS (P=0.230) and OS (P=0.268) were comparable between the two cohorts. The incidence of severe hematologic adverse events (grade≥Ⅲ) was comparable in the two cohorts. Conclusion: Patients receiving initial flumatinib therapy had higher cumulative incidences of therapy responses and higher probability of FFS than those receiving initial imatinib therapy, whereas the incidence of severe hematologic adverse events was comparable between the two cohorts.
Adult ; Humans ; Adolescent ; Imatinib Mesylate/adverse effects* ; Incidence ; Antineoplastic Agents/adverse effects* ; Retrospective Studies ; Pyrimidines/adverse effects* ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Treatment Outcome ; Benzamides/adverse effects* ; Leukemia, Myeloid, Chronic-Phase/drug therapy* ; Aminopyridines/therapeutic use* ; Protein Kinase Inhibitors/therapeutic use*

Objective: To compare digital polymerase chain reaction (dPCR) and real-time quantitative PCR (qPCR) measurements of BCR::ABL (P210) mRNA expression in patients with chronic myeloid leukemia (CML) . Methods: In this non-interventional, cross-sectional study, BCR::ABL (P210) mRNA was simultaneously measured by dPCR and qPCR in peripheral blood samples collected from patients with CML who underwent tyrosine kinase inhibitor therapy and who achieved at least a complete cytogenetic response from September 2021 to February 2023 at Peking University People's Hospital. The difference, correlation, and agreement between the two methods were evaluated using the Wilcoxon signed-rank test, Spearman's correlation, and Bland-Altman analysis, respectively. Results: In total, 459 data pairs for BCR::ABL mRNA expression measured by dPCR and qPCR from 356 patients with CML were analyzed. There was a significant difference in BCR::ABL mRNA expression between the two methods (P<0.001). When analyzed by the depth of the molecular response (MR), a significant difference only existed for patients with ≥MR4.5 (P<0.001). No significant difference was observed for those who did not achieve a major MR (no MMR; P=0.922) or for those who achieved a major MR (MMR; P=0.723) or MR4 (P=0.099). There was a moderate correlation between the BCR::ABL mRNA expression between the two methods (r=0.761, P<0.001). However, the correlation gradually weakened or disappeared as the depth of the MR increased (no MMR: r=0.929, P<0.001; MMR: r=0.815, P<0.001; MR4: r=0.408, P<0.001; MR4.5: r=0.176, P=0.176). In addition, the agreement in BCR::ABL mRNA expression between the two methods in those with MR4.5 was weaker than other groups (no MMR: ▉= 0.042, P=0.846; MMR:▉=0.054, P=0.229; MR4:▉=-0.020, P=0.399; MR4.5:▉=-0.219, P<0.001) . Conclusions: dPCR is more accurate than qPCR for measuring BCR::ABL (P210) mRNA expression in patients with CML who achieve a stable deep MR.
Humans ; Cross-Sectional Studies ; Cytogenetics ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/genetics* ; Real-Time Polymerase Chain Reaction ; RNA, Messenger/genetics*

Objective: To develop a scoring system to predict molecular responses in patients with chronic myeloid leukemia in the chronic phase (CML-CP) receiving initial imatinib therapy. Methods: Data from consecutive adults with newly diagnosed CML-CP treated by initial imatinib was interrogated and subjects were distributed randomly into training and validation cohort, in a ratio of 2∶1. Fine-gray models were applied in the training cohort to identify co-variates of predictive value for major molecular response (MMR) and MR4. A predictive system was built using significant co-variates. The predictive system was then tested in the validation cohort and the area under the receiver-operator characteristic curve (AUROC) was used to estimate accuracy of the predictive system. Results: 1 364 CML-CP subjects receiving initial imatinib were included in this study. Subjects were distributed randomly into training cohort (n=909) and validation cohort (n=455) . In the training cohort, the male gender, European Treatment and Outcome Study for CML (EUTOS) Long-Term Survival (ELTS) intermediate-risk, ELTS high-risk, high WBC (≥130×10(9)/L or 120×10(9)/L, MMR or MR4) and low HGB (<110 g/L) at diagnosis were significantly related with poor molecular responses and were given points based on their regression coefficients. For MMR, male gender, ELTS intermediate-risk and low HGB (<110 g/L) were given 1 point; ELTS high-risk and high WBC (≥130×10(9)/L) , 2 points. For MR4, male gender was given 1 point; ELTS intermediate-risk and low HGB (<110 g/L) were given 2 points; high WBC (≥120×10(9)/L) , 3 points; ELTS high-risk, 4 points. We divided all subjects into 3 risk subgroups according to the predictive system above. Cumulative incidence of achieving MMR and MR4 in 3 risk subgroups was significantly different in both training and validation cohort (all P values <0.001) . In the training and validation cohorts, the time-dependent AUROC ranges of MMR and MR4 predictive systems were 0.70-0.84 and 0.64-0.81, respectively. Conclusions: A scoring system combining gender, WBC, HGB level and ELTS risk was built to predict MMR and MR4 in CML-CP patients receiving initial imatinib therapy. This system had good discrimination and accuracy, which could help phsicians optimize the selsction of initial TKI-therapy.
Adult ; Humans ; Male ; Imatinib Mesylate/therapeutic use* ; Antineoplastic Agents/therapeutic use* ; Treatment Outcome ; Protein Kinase Inhibitors/therapeutic use* ; Retrospective Studies ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Chronic Disease

Humans ; Child ; Tyrosine Protein Kinase Inhibitors ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/drug therapy* ; Protein Kinase Inhibitors/therapeutic use* ; Chronic Disease

BACKGROUND: Imatinib mesylate (IM) resistance is an emerging problem for chronic myeloid leukemia (CML). Previous studies found that connexin 43 (Cx43) deficiency in the hematopoietic microenvironment (HM) protects minimal residual disease (MRD), but the mechanism remains unknown. METHODS: Immunohistochemistry assays were employed to compare the expression of Cx43 and hypoxia-inducible factor 1α (HIF-1α) in bone marrow (BM) biopsies of CML patients and healthy donors. A coculture system of K562 cells and several Cx43-modified bone marrow stromal cells (BMSCs) was established under IM treatment. Proliferation, cell cycle, apoptosis, and other indicators of K562 cells in different groups were detected to investigate the function and possible mechanism of Cx43. We assessed the Ca 2+ -related pathway by Western blotting. Tumor-bearing models were also established to validate the causal role of Cx43 in reversing IM resistance. RESULTS: Low levels of Cx43 in BMs were observed in CML patients, and Cx43 expression was negatively correlated with HIF-1α. We also observed that K562 cells cocultured with BMSCs transfected with adenovirus-short hairpin RNA of Cx43 (BMSCs-shCx43) had a lower apoptosis rate and that their cell cycle was blocked in G0/G1 phase, while the result was the opposite in the Cx43-overexpression setting. Cx43 mediates gap junction intercellular communication (GJIC) through direct contact, and Ca 2+ is the key factor mediating the downstream apoptotic pathway. In animal experiments, mice bearing K562, and BMSCs-Cx43 had the smallest tumor volume and spleen, which was consistent with the in vitro experiments. CONCLUSIONS Cx43 deficiency exists in CML patients, promoting the generation of MRD and inducing drug resistance. Enhancing Cx43 expression and GJIC function in the HM may be a novel strategy to reverse drug resistance and promote IM efficacy.
Animals ; Humans ; Mice ; Apoptosis ; Bone Marrow Cells ; Cell Communication ; Connexin 43/genetics* ; Gap Junctions/metabolism* ; Imatinib Mesylate/therapeutic use* ; K562 Cells ; Leukemia, Myelogenous, Chronic, BCR-ABL Positive/pathology* ; Mesenchymal Stem Cells/metabolism* ; Tumor Microenvironment ; Calcium/metabolism*