Leukemia Group Research Articles

Clinical features and long-term prognostic analysis of relapsed pediatric acute lymphoblastic leukemia

Objective: To investigate the clinical characteristics and long-term prognostic factors of relapsed pediatric acute lymphoblastic leukemia (ALL). Methods: Clinical data including the age, time from initial diagnosis to relapse, relapse site, and molecular biological features of 217 relapsed ALL children primarily treated by the Chinese Children's Leukemia Group (CCLG)-ALL 2008 protocol in Institute of Hematology & Blood Diseases Hospital, Chinese Academy of Medical Sciences between April 2008 and April 2015 were collected and analyzed in this retrospective cohort study. Kaplan-Meier analysis was used to evaluate the overall survival (OS) rate and event free survival (EFS) rate for univariate analysis, and Cox proportional-hazards regression model was used to evaluate the influencing factors of OS rate and EFS rate for multivariate analysis. Results: The age at initial diagnosis of 217 relapsed patients was 5 (3, 7) years. There were 135 males and 82 females. The time from initial diagnosis to relapse of 217 children was 22 (10, 39) months. After relapse, 136 out of 217 children (62.7%) received treatment and the follow-up time was 65 (47, 90) months. The 5-year OS rate and EFS rate of the 136 relapsed children were (37±4) % and (26±4) %, respectively. The predicted 10-year OS rate and EFS rate were (35±5) % and (20±4) %, respectively. Univariate analysis showed that the 5-year OS rate in the group of patients with late relapse (43 cases) was significantly higher than those with very early (54 cases) and early relapse (39 cases) ((72±7)% vs. (16±5)%, (28±8)%, χ2=35.91, P<0.05), 5-year OS rate of the isolated extramedullary relapse group (20 cases) was significantly higher than isolated bone marrow relapse group (102 cases) and combined relapse group (14 cases) ((69±11)% vs. (31±5)%, (29±12)%, χ2=9.14, P<0.05), 5-year OS rate of high-risk group (80 cases) was significantly lower than standard-risk group (10 cases) and intermediate-risk group (46 cases) ((20±5)% vs. (90±10)%, (54±8)%, χ2=32.88, P<0.05). ETV6::RUNX1 was the most common fusion gene (13.2%, 18/136). The predicted 10-year OS rate of relapsed children with positive ETV6::RUNX1 was significantly higher than those without ETV6::RUNX1 (118 cases) ((83±9)% vs. (26±5)%, χ2=14.04, P<0.05). The 5-year OS for those accepted hematopoietic stem cell transplantation (HSCT) after relapse (42 cases) was higher than those without HSCT (94 cases) ((56±8)% vs. (27±5)%, χ2=15.18, P<0.05). Multivariate analysis identified very early/early relapse (HR=3.91, 95%CI 1.96-7.79; HR=4.15, 95%CI 1.99-8.67), bone marrow relapse including isolated bone marrow relapse and combined relapse (HR=6.50, 95%CI 2.58-16.34; HR=5.19, 95%CI 1.78-15.16), with ETV6::RUNX1 (HR=0.23, 95%CI 0.07-0.74) and HSCT after relapse (HR=0.24, 95%CI 0.14-0.43) as independent prognostic factors for OS (all P<0.05). Conclusions: Relapsed pediatric ALL mainly occurs very early and often affects bone marrow, which confer poor outcome. ETV6::RUNX1 is the most common genetic aberration with a favorable outcome. HSCT could rescue the outcome of relapsed children, though the survival rate is still poor.

Prognostic Factors in Limited-Stage Small Cell Lung Cancer

The impact of patient-specific, disease-related, and social factors on outcomes in limited-stage small cell lung cancer (LS-SCLC) is not well defined. A post hoc secondary analysis of such factors from the Cancer and Leukemia Group B (CALGB) 30610-Radiation Therapy Oncology Group (RTOG) 0538 trial may impact future trial design. To assess the comprehensive demographic, disease-related, treatment-related, and social factors for potential associations with survival outcomes and understand whether specific subpopulations may benefit from radiotherapy (RT) dose escalation in LS-SCLC. This post hoc secondary analysis of a randomized clinical trial included 638 adults with LS-SCLC treated at 186 unique treatment sites with at least 1 accrual for all patients from March 15, 2008, to December 1, 2019; 313 patients were randomized to receive RT twice daily to a dosage of 45 Gy for 3 weeks and 325 to receive RT once daily to a dosage of 70 Gy for 7 weeks. Data were locked February 28, 2022, and analyzed from November 28, 2022, to June 4, 2024. Twice-daily RT or once-daily RT. Multivariable Cox proportional hazards models evaluated the association of treatment groups and other risk factors with progression-free survival (PFS) and overall survival (OS). Patient-specific factors included age, sex, and Eastern Cooperative Oncology Group performance status. Disease-related factors included tumor, nodal, and overall cancer stages. Treatment-related factors included type of chemotherapy, timing of concurrent RT, RT technique, and prophylactic cranial irradiation. Social factors included marital status and treatment center accrual volume. Among 507 patients (260 [51.3%] female and 247 [48.7%] male; mean [SD] age, 62.6 [7.9] years) included in the multivariate survival analysis, with a median follow-up of 4.7 (IQR, 3.7-7.1) years, female sex was associated with improved OS (hazard ratio [HR], 0.73 [95% CI, 0.58-0.91]; P = .006), while being 70 years or older was associated with decreased OS (HR, 1.50 [95% CI, 1.14-1.98]; P = .004). Neither age nor sex was associated with PFS. When compared with those with N1 disease, OS and PFS were worse in patients with N2 (HRs, 1.64 [95% CI, 1.19-2.26]; P = .002 and 1.36 [95% CI, 1.02-1.81]; P = .04, respectively) and N3 (HRs, 2.03 [95% CI, 1.40-2.93]; P < .001 and 1.63 [95% CI, 1.17-2.26]; P = .004) disease. Compared with stage II cancer, OS was worse for stage IIIA (HR, 1.65 [95% CI, 1.17-2.31]; P = .004) and stage IIIB (HR, 1.94 [95% CI, 1.34-2.83]; P < .001). Compared with high-volume accrual centers, treatment at low- or middle-volume accrual centers was associated with worse PFS (HRs, 1.94 [95% CI, 1.33-2.82; P < .001] and 1.44 [95% CI, 1.15-1.82; P = .002], respectively) and worse OS (HRs, 1.55 [95% CI, 1.03-2.32; P = .03] and 1.33 [95% CI, 1.04-1.70; P = .02], respectively). This secondary analysis of the CALGB 30610-RTOG 0538 randomized clinical trial of patients with LS-SCLC found associations between female sex or being younger than 70 years and improved overall survival and between advanced nodal stage or treatment at low- or middle-volume accrual centers and worse outcomes. These findings suggest that stratification by nodal stage, clinical stage, and age should be considered in future randomized trials. ClinicalTrials.gov Identifier: NCT00632853.

DAC and CLAM are equally effective as early second induction in newly diagnosed AML patients with persistent leukemia in early bone marrow evaluation – a retrospective analysis of Polish Adult Leukemia Group

DAC and CLAM are equally effective as early second induction in newly diagnosed AML patients with persistent leukemia in early bone marrow evaluation – a retrospective analysis of Polish Adult Leukemia Group

Ibrutinib plus rituximab and mini-CHOP in older patients with newly diagnosed DLBCL: a phase 2 ALLG study

AbstractThe multicenter, prospective phase 2 Australasian Leukaemia & Lymphoma Group NHL29 trial was conducted to assess the addition of ibrutinib to R-mini-CHOP (dose attenuated R-CHOP; rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone) in patients aged ≥75 years with newly diagnosed diffuse large B-cell lymphoma (DLBCL). Treatment consisted of six 21-day cycles of ibrutinib–R-mini-CHOP followed by two 21-day cycles of R-ibrutinib. Coprimary end points were deliverability and 2-year overall survival (OS). The median average relative total dose and average relative dose intensity for the entire regimen were both 97% (interquartile range, 82-100 and 88-100, respectively). With a median follow-up of 35.5 months, the 2-year OS was 68% (95% confidence interval [CI], 55.6-77.4) with a 2-year progression-free survival (PFS) of 60.0% (95% CI, 47.7-70.3). Median OS and PFS were 72 months (95% CI, 35 to not reached) and 40 months (95% CI, 20.4 to not reached), respectively. The overall response rate was 76% (61/79) of patients, with a complete response rate of 71% (56/79). Deaths occurred in 34 of 79 patients (43%), including 17 from progressive disease and 5 treatment related. Overall, 67% patients experienced at least 1 serious adverse event. Most common adverse events were infections and diarrhea (the majority grade 1-2). In both health-related quality of life measures, there was an improvement in functional and symptom scales, median health state classification score, and median visual analogue scale in responders over time. In conclusion, this study showed that the addition of ibrutinib to R-mini-CHOP was both deliverable and efficacious in elderly DLBCL patients.

Diagnostic genomic analysis is prognostic in AYA patients with ALL treated on an MRD-stratified pediatric protocol

AbstractOver the last decade, next-generation sequencing has enabled classification of multiple new recurrent genomic drivers of acute lymphoblastic leukemia (ALL). The aim of this study was to describe the genomic drivers of ALL in an adolescent and young adult (AYA) cohort (ALL06; target age, 15-39 years; recruited age, 16.6-39 years), treated uniformly on a pediatric-inspired protocol (the Australasian Leukaemia and Lymphoma Group ALL06 study). ALL06 assessed the safety and efficacy of adapting a pediatric chemotherapy protocol in older patients. Genomic risk classification of patients with B-cell ALL (B-ALL) and T-cell ALL (T-ALL) enrolled to the study was based on the use of multiple assays: messenger RNA sequencing, multiplex ligation-dependent probe amplification, immunophenotyping, and cytogenetics. Using this approach, 36 of 40 (90%) patients with B-ALL and 13 of 17 (76.5%) patients with T-ALL were classified according to genomic risk. A strong correlation existed between adverse genomic risk and minimal residual disease (MRD) at the end of consolidation, translating to inferior overall and relapse free survival. Patients with adverse risk genomics who achieved negative MRD status had improved responses compared with those with persistent MRD. Patients with standard-risk genomics had excellent responses regardless of MRD status. This is, to our knowledge, the first report of the impact of genomics in an individual cohort of AYA patients treated on a single protocol. These data argue strongly for incorporation of a genomic risk classification into future ALL treatment paradigms at the time of diagnosis, and also for the rigorous assessment of risk assignments in a group of patients who are not children and not older adults. This trial was registered at https://anzctr.org.au/ as #ACTRN12611000814976.

Glycated albumin may have a complementary role to glycated hemoglobin in glucose monitoring in childhood acute leukemia.

Glycated hemoglobin (HbA1c) as a glycemic index may have limited value in pediatric patients with acute leukemia as they often present with anemia and/or pancytopenia. To address this issue, we evaluated the usefulness of glycated albumin (GA) as a glycemic monitoring index in pediatric patients with acute leukemia. Medical records of 25 patients with type 2 diabetes mellitus (T2DM), 63 patients with acute leukemia, and 115 healthy children from Seoul St. Mary's Hospital, The Catholic University of Korea, were retrospectively investigated for serum GA, HbA1c, and fasting blood glucose (FBG) levels, along with demographic data. GA, HbA1c, and FBG levels did not differ between the control and acute leukemia groups. In the T2DM group, positive correlations were observed among GA, HbA1c, and FBG (P<0.01). Although GA level was not associated with the HbA1c level in the control group, GA and HbA1c levels showed a positive correlation in the acute leukemia group (P=0.045). Regression analysis revealed GA and HbA1c levels to be positively correlated in the acute leukemia and T2DM groups even after adjusting for age, sex, and body mass index z-score (P=0.007, P<0.01). GA may be a useful complementary parameter to HbA1c for glycemic monitoring in pediatric patients with acute leukemia, similar to its use in patients with T2DM.

Prognostic significance and treatment strategies for IKZF1 deletion in pediatric B-cell precursor acute lymphoblastic leukemia

BackgroundThe predictive importance of IKZF1del in pediatric B-cell precursor acute lymphoblastic leukemia (BCP-ALL) has shown variability across different studies. Thus, the optimal treatment approach for children with IKZF1del BCP-ALL remains contentious, with the ongoing debate surrounding the use of IKZF1del-based high-risk stratification versus a minimal residual disease (MRD)-guided protocol.MethodsIKZF1 status was reliably determined in 804 patients using multiplex ligation-dependent probe amplification (MLPA) data obtained from four hospitals in Fujian, a province of China. In the Chinese Children Leukemia Group (CCLG)-ALL 2008 cohort, IKZF1 status was included in the risk assignment, with all IKZF1del patients receiving a high-risk regimen. Conversely, in the Chinese Children’s Cancer Group (CCCG)-ALL 2015 cohort, IKZF1del was not incorporated into the risk assignment, and patients were treated based on an MRD-guided risk stratification protocol.ResultsIKZF1del was found in 86 patients (86/804, 10.7%) overall and in 30 (30/46, 65.2%) BCR::ABL1-positive patients. Overall, IKZF1del was a poor prognostic predictor for patients, though the significance diminished upon age adjustment, white blood cell (WBC) count at diagnosis, treatment group, and MRD status. In the CCLG-ALL 2008 cohort, IKZF1del conferred a notably lower 5-year overall survival (OS) and event-free survival (EFS) and a significantly higher 5-year cumulative incidence of relapse (CIR) than IKZF1wt. In the CCLG-ALL 2015 cohort, IKZF1del conferred a lower 5-year OS and EFS and a higher 5-year CIR than IKZF1wt, but the differences were insignificant. The IKZF1del patients treated with higher intensity chemotherapy (CCLG-ALL 2008 high-risk regimen) had a markedly lower 5-year OS and EFS compared with those treated with the MRD-guided protocol (CCCG-ALL 2015 protocol). Furthermore, patients treated with the CCLG-ALL 2008 high-risk regimen experienced a higher frequency of serious adverse events (SAEs), especially infection-related SAEs, compared with those treated with the CCCG-ALL 2015 MRD-guided protocol.ConclusionsThe prognostic effect of IKZF1del may vary in different protocols. Compared with higher intensity chemotherapy, the MRD-guided protocol may be a more effective approach to treating BCP-ALL with IKZF1del in children.

Analysis of the occurrence and liver function characteristics of arsenic-associated liver injury during the treatment of pediatric patients with acute promyelocytic leukemia.

Liver injury during arsenic treatment for acute promyelocytic leukemia was previously reported in adults, but not comprehensively in children until now. This study aims to investigate liver injury in pediatric patients with APL, changes in liver function during treatment, and compare the effects of Arsenic trioxide (ATO) and Realgar-Indigo naturalis formula (RIF) on liver function. One hundred and eighty-six patients with 3076 patient tests were analyzed, who were enrolled in the Chinese Children's Leukemia Group (CCLG)-APL2016 Protocol database between November 2016 and November 2018 in 38 hospitals across China(ChiCTR-OIN-17011227). Twenty of 164 patients (12.2%) suffered from liver injury after treatment with arsenic. In addition, sixteen (80%) cases of liver injury occurred during the induction period of treatment. What's not disheartening was that 18 (90%) cases of liver injury were transient, occurring at a median time of 17 days after exposure to arsenic. More importantly, the risk of liver injury associated with RIF was not higher than that associated with ATO (RR = 0.854, 95% CI: 0.292-2.495). Otherwise, the ALP of 18 cases of liver injury was not higher than the ULN of ALP. Thus, the incidence of liver injury associated with arsenic in pediatric patients with APL was similar to that in adult patients and the risk of liver injury associated with RIF was not higher than that associated with ATO. Since ALP was not higher in pediatric APL patients with liver injury, further research is needed to explore whether ALP is an index of liver injury in children.

Asciminib monotherapy as frontline treatment of chronic phase chronic myeloid leukemia: results from the ASCEND study

AbstractAsciminib is a myristoyl site BCR::ABL1 inhibitor approved for patients with chronic phase chronic myeloid leukemia (CP-CML) failing ≥2 prior lines of therapy. The Australasian Leukaemia and Lymphoma Group conducted the Asciminib Evaluation in Newly Diagnosed CML study to assess efficacy of asciminib for newly diagnosed CP-CML. Patients commenced asciminib 40 mg twice daily. Patients with treatment failure, defined as BCR::ABL1 of >10% at 3 or 6 months, or >1% at 12 or 18 months, received either imatinib, nilotinib, or dasatinib in addition to asciminib. In patients with suboptimal response, defined as levels of 1% to 10% at 6 months, >0.1% to 1% at 12 months, or >0.01% to 1% at 18 months, the asciminib dose was increased to 80 mg twice daily. With a median follow-up of 21 months (range, 0-36), 82 of 101 patients continue asciminib. Most common reasons for treatment discontinuation were adverse events (6%), loss of response (4%), and withdrawn consent (5%). There were no deaths; 1 patient developed lymphoid blast crisis. The coprimary end points were early molecular response (BCR::ABL1 of ≤10% at 3 months), achieved in 93% (96% confidence interval [CI], 86-97%), and major molecular response by 12 months achieved in 79%; (95% CI, 70-87%), respectively. Cumulative incidence of molecular response 4.5 was 53% by 24 months. One patient had 2 cerebrovascular events; no other arterial occlusive events were reported. Asciminib as frontline CP-CML therapy leads to high rates of molecular response with excellent tolerance and a low rate of discontinuation for toxicity. This trial was registered at https://www.anzctr.org.au/ as #ACTRN12620000851965.

Glucocorticoid Sensitivity Among Young Survivors of Childhood Acute Lymphoblastic Leukemia: What Does It Matter?

The aim of the study was to assess glucocorticoid sensitivity in survivors of childhood acute lymphoblastic leukemia using in vivo and in vitro tests. Thirty leukemia survivors of both sexes aged ≥18 years participated in the study and at least two years after therapy withdrawal. In vivo tests comprised: a) a very low dose intravenous dexamethasone suppression test for measurement of serum cortisol before, after, and % suppression, compared with 32 age-matched controls; and b) 0.25 mg overnight oral dexamethasone suppression test for assessment of salivary cortisol before, after, and % suppression. In vitro methods comprised: c) glucocorticoid receptor polymorphisms: BcI1-NR3C1 and A3669G; and d) splicing variant of glucocorticoid receptor GR-α mRNA by real-time quantitative polymerase chain reaction, compared with 32 controls. There was a reduction in salivary cortisol, and 73.3% of leukemia survivors showed high sensitivity according to % suppression after oral dexamethasone (p<0.05). Serum cortisol at baseline, after the test, % suppression after intravenous dexamethasone, and the percentage of high sensitivity were reduced in the leukemia group (%F=36.7; p<0.05). The BcI1-NR3C1 and A3669G polymorphisms were present in 11/30 (36.7%) and 5/30 (16.7%) patients, respectively. GR-α mRNA levels were lower in the leukemia group than in the controls (p<0.05). Survivors of acute lymphoblastic leukemia presented with reduced glucocorticoid sensitivity. Glucocorticoid sensitivity allows individualized treatment to avoid adverse effects and may be involved in cardiovascular disease risk among this particular group of cancer survivors.

Recurrence of Non–Small Cell Lung Cancer With Visceral Pleural Invasion

The randomized clinical trial Cancer and Leukemia Group B (CALGB) 140503 showed that for patients with clinically staged T1N0 non-small cell lung cancer (NSCLC; ≤2 cm), sublobar resections were associated with similar oncological outcomes to those after lobar resection. The association of the extent of parenchymal resection with recurrence and survival in patients with tumors pathologically upstaged to T2 based on visceral pleural invasion (VPI) is controversial. To determine survival and recurrence rates in patients with small peripheral pT2 NSCLC (≤2 cm) that was treated by either lobar or sublobar resection in CALGB 140503. CALGB 140503, a randomized multicenter noninferiority trial, included 697 patients with small peripheral NSCLC that was clinically staged as T1N0. Enrollment was from June 2007 through March 2017 at 83 participating institutions, and after a median follow-up of 7 years, the primary outcome of disease-free survival after sublobar resection was noninferior to that after lobar resection. Lobar or sublobar resection. Survival end points were estimated by the Kaplan-Meier estimator. Hazard ratios and 95% CIs were estimated using stratified Cox proportional hazard models. Of 679 participants, 390 (57.4%) were female, and the median (range) age was 67.8 (37.8-89.7) years. Among 697 patients randomized, 566 (81.2%) had pT1 tumors (no VPI) and 113 (16.2%) had pT2 tumors (VPI). Five-year disease-free survival was 65.9% (95% CI, 61.9%-70.2%) in patients with pT1 compared with 53.3% (95% CI, 44.3%-64.1%) in patients with pT2 tumors (stratified log-rank: P = .02). Disease recurrence developed in 27.6% of patients with pT1 (locoregional only: 60 [10.8%]; distant only: 81 [14.6%]) and 41.6% of those with pT2 (locoregional only: 17 [15.0%]; distant only: 27 [23.9%]). Five-year recurrence-free survival was 73.1% (95% CI, 69.2%-77.1%) for pT1 tumors and 58.2% (95% CI, 49.2%-68.8%) for pT2 tumors (stratified log-rank: P = .01). There were no intergroup differences in disease-free or recurrence-free survival based on the extent of parenchymal resection. The results of this secondary analysis suggest that compared with patients with tumors without VPI, patients who had tumors with VPI had worse disease-free and recurrence-free survival and a higher rate of local and distant disease recurrence. These high rates of recurrence were independent of the extent of parenchymal resection, and these data support the inclusion of these patients in adjuvant therapy trials. ClinicalTrials.gov Identifier: NCT0049933.

Treatment of three pediatric AML co-expressing NUP98-NSD1, FLT3-ITD, and WT1

During the treatment of 89 pediatric patients with Acute Myeloid Leukemia (AML) at the Hematology Department of Kunming Medical University’s Children’s Hospital from 2020 to 2023, three patients were identified to co-express the NUP98-NSD1, FLT3-ITD, and WT1 gene mutations. The bone marrow of these three patients was screened for high-risk genetic mutations using NGS and qPCR at the time of diagnosis. The treatment was administered following the China Children’s Leukemia Group (CCLG)-AML-2019 protocol. All three patients exhibited a fusion of the NUP98 exon 12 with the NSD1 exon 6 and co-expressed the FLT3-ITD and WT1 mutations; two of the patients displayed normal karyotypes, while one presented chromosomal abnormalities. During the induction phase of the CCLG-AML-2019 treatment protocol, the DAH (Daunorubicin, Cytarabine, and Homoharringtonine) and IAH (Idarubicin, Cytarabine, and Homoharringtonine) regimens, in conjunction with targeted drug therapy, did not achieve remission. Subsequently, the patients were shifted to the relapsed/refractory chemotherapy regimen C + HAG (Cladribine, Homoharringtonine, Cytarabine, and G-CSF) for two cycles, which also failed to induce remission. One patient underwent Haploidentical Hematopoietic Stem Cell Transplantation (Haplo-HSCT) and achieved complete molecular remission during a 12-month follow-up period. Regrettably, the other two patients, who did not receive transplantation, passed away. The therapeutic conclusion is that pediatric AML patients with the aforementioned co-expression do not respond to chemotherapy. Non-remission transplantation, supplemented with tailor-made pre- and post-transplant strategies, may enhance treatment outcomes.

Current situation and prospect of diagnosis and therapy of childhood acute leukemia in China

Acute leukemia is the most common hematopoietic stem cell malignant tumor in children, which ranks in the top one of the incidence of tumor in children, it is a major disease that affects the growth and survival of children. With the continuous improvement of medical diagnosis and treatment and the extensive development of immunotherapy, the survival rate and quality of life of children with acute leukemia have been significantly improved. In recent years, three cooperative groups of childhood leukemia have been established in China, and a series of high-level research results have been published. In the future, efforts should be made to promote the process of standardization and homogenization in the diagnosis and treatment of children's acute leukemia, explore the monitoring targets of sensitive residual diseases, and find the best treatment for refractory/recurrent cases. Speeding up the clinical research of new drugs will be an urgent problem and development direction in the field of acute leukemia diagnosis and treatment in children.

Risk factors for recurrence of childhood acute lymphoblastic leukemia after treatment with the Chinese Children's Cancer Group ALL-2015 protocol

To investigate the cumulative incidence of recurrence (CIR) in children with acute lymphoblastic leukemia (ALL) after treatment with the Chinese Children's Cancer Group ALL-2015 (CCCG-ALL-2015) protocol and the risk factors for recurrence. A retrospective analysis was conducted on the clinical data of 852 children who were treated with the CCCG-ALL-2015 protocol from January 2015 to December 2019. CIR was calculated, and the risk factors for the recurrence of B-lineage acute lymphoblastic leukemia (B-ALL) were analyzed. Among the 852 children with ALL, 146 (17.1%) experienced recurrence, with an 8-year CIR of 19.8%±1.6%. There was no significant difference in 8-year CIR between the B-ALL group and the acute T lymphocyte leukemia group (P>0.05). For the 146 children with recurrence, recurrence was mainly observed in the very early stage (n=62, 42.5%) and the early stage (n=46, 31.5%), and there were 42 children with bone marrow recurrence alone (28.8%) in the very early stage and 27 children with bone marrow recurrence alone (18.5%) in the early stage. The Cox proportional-hazards regression model analysis showed that positive MLLr fusion gene (HR=4.177, 95%CI: 2.086-8.364, P<0.001) and minimal residual disease≥0.01% on day 46 (HR=2.013, 95%CI: 1.163-3.483, P=0.012) were independent risk factors for recurrence in children with B-ALL after treatment with the CCCG-ALL-2015 protocol. There is still a relatively high recurrence rate in children with ALL after treatment with the CCCG-ALL-2015 protocol, mainly bone marrow recurrence alone in the very early stage and the early stage, and minimal residual disease≥0.01% on day 46 and positive MLLr fusion gene are closely associated with the recurrence of B-ALL.

Clinical characteristics and prognosis of childhood acute lymphoblastic leukemia with CD123 expression

To investigate the expression of CD123 in children with acute lymphoblastic leukemia (ALL) and its effect on the clinical characteristics and prognosis of children with B-lineage acute lymphoblastic leukemia (B-ALL). A retrospective analysis was conducted on the clinical data of 251 children with ALL who were admitted to the Department of Hematology and Oncology, Children's Hospital of Kunming Medical University, from December 2019 to June 2022. According to the expression of CD123 at initial diagnosis, the children were divided into CD123+ group and CD123- group, and the two groups were compared in terms of clinical characteristics and treatment outcome. The factors influencing the prognosis were analyzed. Among the 251 children with ALL, there were 146 children (58.2%) in the CD123+ group. The B-ALL group had a significantly higher positive expression rate of CD123 than the acute T lymphocyte leukemia group (P<0.05). Compared with the CD123- group, the CD123+ group had significantly lower peripheral blood leukocyte count and percentage of juvenile cells and a significantly higher proportion of children with high hyperdiploid karyotype or an age of 1-10 years, with a relatively low proportion of children with E2A-PBX1 fusion gene (P<0.05). The multivariate Cox proportional-hazards regression model analysis showed that compared with the >10 years group, the 1-10 years group had a significantly higher overall survival rate (P<0.05), and compared with the high risk group, the moderate risk group had a significantly higher event-free survival rate in children with B-ALL (P<0.05). CD123 is widely expressed in children with B-ALL, and positive expression of CD123 might be an indicator for good prognosis in children with B-ALL, which is of great significance for evaluating the efficacy of remission induction therapy and survival prognosis of children with B-ALL.

Epigenetic alterations affecting hematopoietic regulatory networks as drivers of mixed myeloid/lymphoid leukemia

Leukemias with ambiguous lineage comprise several loosely defined entities, often without a clear mechanistic basis. Here, we extensively profile the epigenome and transcriptome of a subgroup of such leukemias with CpG Island Methylator Phenotype. These leukemias exhibit comparable hybrid myeloid/lymphoid epigenetic landscapes, yet heterogeneous genetic alterations, suggesting they are defined by their shared epigenetic profile rather than common genetic lesions. Gene expression enrichment reveals similarity with early T-cell precursor acute lymphoblastic leukemia and a lymphoid progenitor cell of origin. In line with this, integration of differential DNA methylation and gene expression shows widespread silencing of myeloid transcription factors. Moreover, binding sites for hematopoietic transcription factors, including CEBPA, SPI1 and LEF1, are uniquely inaccessible in these leukemias. Hypermethylation also results in loss of CTCF binding, accompanied by changes in chromatin interactions involving key transcription factors. In conclusion, epigenetic dysregulation, and not genetic lesions, explains the mixed phenotype of this group of leukemias with ambiguous lineage. The data collected here constitute a useful and comprehensive epigenomic reference for subsequent studies of acute myeloid leukemias, T-cell acute lymphoblastic leukemias and mixed-phenotype leukemias.

Children with cancer need tailored support

Young Lives vs Cancer, Children's Cancer and Leukaemia Group, Ellen MacArthur Cancer Trust, and Teenage Cancer Trust

MDB-23. MULTICENTRE EVALUATION OF THE MANAGEMENT OF CHILDREN WITH HIGH RISK MEDULLOBLASTOMA: REAL WORLD PERFORMANCE OF THE SJMB03 AND COG99701 PROTOCOLS

Abstract BACKGROUND Several treatment protocols are used in the treatment of patients with high risk medulloblastoma (HRMB). In 2015 the UK Children’s Cancer and Leukaemia Group issued interim guidance recommending treatment as per the SJMB03 protocol, whilst also recognising that the COG99701 protocol may be used. Patients were defined as high risk, if metastatic at presentation, large cell anaplastic histology, MYC amplification, significant residual disease or MYCN amplification, the latter two, more recently only if other adverse features present. METHODS We present a retrospective multi-centre service evaluation of treatment of patients with HRMB at 5 tertiary paediatric oncology centres in the UK. Patients were included if treated for HRMB with SJMB03, COG-99701. Patients were excluded if treated for HRMB on other protocols, including the SIOP HRMB trial, or if initially treated for standard risk medulloblastoma and subsequently treated with these protocols due to upstaging or disease progression. Event free, and overall (EFS and OS) survival analyses were calculated from date of primary resection. RESULTS 59 patients were included (median age 8 years, range 3-19): 26 treated as per SJMB03, 33 as per COG-99701. 5-year OS was 83% (95% Confidence Interval, 73-94%) and 5-year EFS was 66% (54-80%). For patients treated as per SJMB03 5-year OS and EFS was 79% (65-97%) and 70% (55-92%)respectively. and for patients treated as per COG99701, 5-year OS and EFS was 86% (73-99%) and 60% (44-83%). There was a higher incidence of grade 3 &amp; 4 ototoxicity (44% vs 6%) and a higher rate of admission to paediatric intensive care (36% vs 6%) in patients treated as per SJMB03 compared to those treated with COG97701 (p&amp;lt;0.05). CONCLUSIONS These real-world outcomes of patients treated in the UK for HRMB are consistent with the published literature for their outcomes for high risk medulloblastoma.

No advantage of antimicrobial prophylaxis in AML/MDS/CMML patients treated with azacitidine—a prospective multicenter study by the Polish Adult Leukemia Group

No advantage of antimicrobial prophylaxis in AML/MDS/CMML patients treated with azacitidine—a prospective multicenter study by the Polish Adult Leukemia Group

Metabolic determinants of leukemia onset variability in genetically homogeneous AKR mice

Leukemia is a complex disease shaped by the intricate interplay of genetic and environmental factors. Given our preliminary data showing different leukemia incidence in genetically homogenous AKR mice harboring the spontaneous leukemia-inducing mutation Rmcfs, we sought to unravel the role of metabolites and gut microbiota in the leukemia penetrance. Our metabolomic analysis revealed distinct serum metabolite profiles between mice that developed leukemia and those that did not. We discovered that linoleic acid (LA), an essential ω-6 polyunsaturated fatty acid, was significantly decreased in the leukemia group, with the lower levels observed starting from 25 weeks before the onset. A predictive model based on LA levels demonstrated high accuracy in predicting leukemia development (area under curve 0.82). In vitro experiment confirmed LA's cytotoxic effects against leukemia cells, and in vivo study showed that a diet enriched with LA prolonged survival in AKR mice. Furthermore, gut microbiome analysis identified specific Lachnospiraceae species, that affect host lipid metabolism, are exclusively present in the leukemia group, suggesting their potential influence on LA metabolism and leukemia development. These findings shed light on the complex relationship between metabolites, gut microbiota, and leukemia development, providing valuable insights into the role of non-genetic factors in leukemia penetrance and potential strategies for leukemia prevention.