Coexistence of ETV6-RUNX1 and MLL aberration among pediatric acute lymphoblastic leukemia: case reports and a literature review.

Background: It is known that ETV6-RUNX1 is usually related to favorable prognosis, but MLL aberration has been associated with poor prognosis among pediatric acute lymphoblastic leukemia (ALL). However, the outcome of coexistence of ETV6-RUNX1 and MLL aberration in pediatric ALL patients is unknown. Herein, we report 4 cases of the coexistence of ETV6-RUNX1 and MLL-partial tandem duplications (MLL-PTD) in pediatric ALL patients and show the favorable outcome, which was never reported before. Case Description: The frequency of coexistence of ETV6-RUNX1 and MLL aberration at our children's medical center was calculated as 0.98% (4/410). All of them were ETV6/RUNX1-positive cases that exhibited MLL-PTD, and the 10-year event-free survival (EFS) and overall survival (OS) were both 75%. With the following keywords of "ETV6-RUNX1", "MLL", "children" and "acute lymphoblastic leukemia", a literature search of coexistence of ETV6-RUNX1 and MLL aberration was conducted in the database of PubMed, and 4 articles were retrieved finally, involving 16 cases of children. Among the 16 cases of pediatric ALL, the age ranged from 2 to 7 years old, including 9 males and 7 females and the white blood cell (WBC) count was (2.66-68.6)×109/L. In terms of fusion genes, they all had positive ETV6/RUNX1. Among them, MLL deletion was exhibited among 8 ETV6/RUNX1-positive patients, and 2 cases of der(21) duplication. MLL allelic deletions were shown among the remaining ETV6/RUNX1-positive patients. All patients showed a favorable outcome. Conclusions: The results of our analysis primarily provide compelling evidence that cases with an MLL-PTD or other types of MLL aberration are in fact a distinct subentry among ETV6-RUNX1 B-cell ALL (B-ALL).

[Relationship between MTHFR Gene Polymorphism(C677T) and Adverse Reactions of High-Dose Methotrexate in Pediatric Patients with Acute Lymphoblastic Leukemia].

OBJECTIVE: To explore the effects of methylenetetrahydrofolate reductase (MTHFR) C677T gene polymorphism on the adverse reactions of high-dose methotrexate (MTX) in pediatric patients with acute lymphoblastic leukemia (ALL). METHODS: A total of 69 children with ALL admitted to the department of Pediatrics of Sun Yat-sen Memorial Hospital of Sun Yat-sen University from November 2018 to October 2020 were included in this study. The clinical data of the children were collected, leukocytes were isolated from their peripheral blood, and MTHFR genotyping was performed by digital fluorescence molecular hybridization techniques. The adverse reactions and plasma drug concentration of MTX were monitored during the chemotherapy. Moreover, the effect of MTHFR gene polymorphism on MTX adverse reactions and plasma drug concentration were analyzed. RESULTS: Among the middle and high risk children, compared with the wildtype group (CC genotype), patients with MTHFR C677T mutations (CT+TT genotypes) had a higher risk of leukopenia (OR=2.38), neutropenia (OR=2.2), anemia (OR=1.83) and hepatoxicity (OR=1.98). However, no significant difference was found in the MTX plasma concentration between the MTHFR C677T mutantion group and the wildtype group at different timepoints (24 h, 48 h and 72 h). Multivariate analysis revealed that the plasma concentration of MTX (48 h), clinical risk level of ALL and MTHFR C677T gene polymorphism were independent factors for the adverse reactions of high-dose MTX. CONCLUSION: The MTHFR C677T mutations may be associated with myelosuppression and hepatotoxicity in children with ALL after high-dose MTX treatment.

Ruxolitinib inhibits the proliferation and induces the apoptosis of MLL-r ALL cells through inactivating JAK/STAT signaling pathway.

Background: The childhood patients with mixed-lineage leukemia rearrangement (MLL-r) gene have worse outcome than non-MLL, and thus often treated with high-risk chemotherapy regimens, so targeted therapy is important for this type of leukemia. This purpose of study was to explore the effects of ruxolitinib on the proliferation, apoptosis, and cell cycle of Nalm-6 cells. Methods: In this study, human acute lymphoblastic leukemia (ALL) cell line Nalm-6 was used as the research object. By constructing an MLL overexpression vector to transfect Nalm-6 cells, exogenous JAK2/STAT3 signal pathway inhibitor ruxolitinib was applied to observe the proliferation, apoptosis, and cell cycle changes of the transfected Nalm-6 cells. Western blot was performed to determine the proteins (MLL-BP, JAK, STAT) involved in the mechanism of action of MLL-r leukemia. CCK8 assay and flow cytometry (FCM) were used for testing the proliferation and apoptosis among MLL-BP transfected Nalm-6 cells. Results: Firstly, we determine the IC50 of ruxolitinib on Nalm-6 cells. Secondly, FCM and CCK8 showed that ruxolitinib dosedependentlyinhibits proliferation of Nalm-6 cells by blocking the cell cycle at G0/G1 phase. In addition, FCM showed that ruxolitinib promoted the apoptosis of MLL-BP transfected Nalm-6 cells. Mechanistically, ruxolitinib inactivated JAK/STAT signaling pathway in MLL-BP transfected Nalm-6 cells, mediating ruxolitinib's inhibition of cell proliferation, and inducing apoptosis. Finally, ruxolitinib significantly inhibited the proliferation of MLL-r ALL cells and promoted their apoptosis. Conclusions: These data provide compelling evidence that ruxolitinib is a promising agent against MLL-r leukemia cell line. However, it needs going through multiple more steps to confirm before it can be an option in clinical practice.

Outcome and prognostic factors of CBF pediatric AML patients with t(8;21) differ from patients with inv(16).

PURPOSE: To explore the outcome and prognostic factors between inv(16) and t(8;21) disrupt core binding factor (CBF) in acute myeloid leukemia (AML). METHODS: The clinical characteristic, probability of achieving complete remission (CR), overall survival (OS) and cumulative incidence of relapse (CIR) were compared between inv(16) and (8;21). RESULTS: The CR rate was 95.2%, 10-year OS was 84.4% and CIR was 29.4%. Subgroup analysis showed that patients with t(8;21) had significant lower 10-year OS and CIR than patients with inv(16). Unexpectedly, there was a trend for pediatric AML receiving five courses cytarabine to have a lower CIR than four courses cytarabine (19.8% vs 29.3%, P = 0.06). Among the cohort of no-gemtuzumab ozogamicin(GO) treatment, inv (16) patients showed a similar 10-year OS (78.9% vs 83.5%; P = 0.69) and an inferior outcome on 10-year CIR (58.6% vs 28.9%, P = 0.01) than those patients with t(8;21). In contrast, inv (16) and t(8;21) patients receiving GO treatment had comparable OS (OS: 90.5% vs. 86.5%, P = 0.66) as well as CIR (40.4% vs. 21.4%, P = 0.13). CONCLUSION: Our data demonstrated that more cumulative cytarabine exposure could improve the outcome of childhood patients with t(8;21), while GO treatment was beneficial to the pediatric patients with inv(16).

Vincristine and dexamethasone pulses in addition to maintenance therapy among pediatric acute lymphoblastic leukemia (GD-ALL-2008): An open-label, multicentre, randomized, phase III clinical trial.

The efficacy and safety on the addition of vincristine (VCR) and dexamethasone (DEX) pulses to maintenance therapy among childhood acute lymphoblastic leukemia (ALL) remain uncertain. Herein, we perform an open-label, multicentre, randomized, phase III clinical trial that was conducted at nine major medical centers in Guangdong Province, China. Patients were randomly assigned either the conventional maintenance therapy (control group, n = 384) or the VCR/DEX pulse (treatment group, n = 375). When limited to the SR cohort, 10-year EFS was 82.6% (95% CI: 75.9-89.9) in the control group and 80.7% (95% CI: 74-88.1) in the treatment group (pnon-inferiority  = .0002). Similarly, patients with IR also demonstrated non-inferiority of the treatment group to the control group in terms of 10-year EFS (73.6% [95% CI: 67.6-80] vs. 77.6% [95% CI: 71.8-83.9]; pnon-inferiority  = .005). Among the HR cohort, compared with the control group, patients in the treatment group experienced a significant benefit in terms of 10-year EFS (61.1% [95% CI: 47.7-78.2] vs. 72.6% [95% CI: 55.6-94.7], p = .026) and a trend toward higher 10-year OS (73.8% [95% CI: 61.6-88.4] vs. 87.9% [95% CI: 579.2-97.5], p = .068). In the HR cohort, the total rate of drug-induced liver injury and Grade 3 chemotherapy-induced anemia were both lower for patients in the treatment group than in the control group (55.6% vs. 100%, p = .033; 37.5% vs. 60%, p = .036). Conversely, the total prevalence of chemotherapy-induced thrombocytopenia was higher for patients in the treatment group than in the control group (88.9% vs. 40%, p = .027). Pediatric acute lymphoblastic leukemia with high risk is suitable to VCR/DEX pulse during maintenance phase for the excellent outcome, while the standard-to-intermediate-risk patients could eliminate the pulses.

Chidamide as maintenance after chemotherapy or hematopoietic stem cell transplantation in 27 children with T-cell lymphoblastic leukemia: A real-world prospective study.

Background: The long-term overall survival of children with T-cell acute lymphoblastic leukemia (T-ALL) is limited to approximately 80-85% because of a high incidence of relapse after achieving remission with intensive chemotherapy and hematopoietic stem cell transplantation (HSCT). Novel treatment strategies inducing long-term remission are needed to improve the outcome. Histone deacetylase inhibitors (HDACis) have been reported to be effective in a series of T-ALL cases. Preclinical studies suggested that T-ALL cells are sensitive to Chidamide, which is a selective HDACi. Methods: This preliminary clinical study evaluated the efficacy and safety of Chidamide in combination with chemotherapy or post-HSCT for children with T-ALL at a dose of 0.5 mg/kg weight of patient twice per week for at least 6 months. Results: In total, 27 children with a mean age of 7.88 years were included. The high-risk proportion was 66.7%. After a median follow-up period of 37.8 months (9.5-67.9 months), the overall survival and event-free survival in the patients treated with Chidamide were 94.1 and 95.2%, respectively. All patients except two maintained persistent remission with <0.01% blast cells in minimal residual disease. Conclusion: The combination therapy with Chidamide in a case series of T-ALL shows the promising clinical efficacy and good safety in children. Clinical trial registration: https://www.chictr.org.cn/, identifier ChiCTR2000030357.

Mutational landscape and clinical outcome of pediatric acute myeloid leukemia with 11q23/KMT2A rearrangements.

BACKGROUND: Alterations of 11q23/KMT2A are the most prevalent cytogenetic abnormalities in acute myeloid leukemia (AML) and the prognostic significance of 11q23/KMT2A-rearranged AML based on various translocation partners varies among different studies. However, few studies evaluated the molecular characteristics of 11q23/KMT2A-rearranged pediatric AML. We aim to analyze the mutational landscape of 11q23/KMT2A-rearranged AML and assess their prognostic value in outcomes. METHODS: The mutational landscape and clinical prognosis of 105 children with 11q23/KMT2A-rearranged AML in comparison with 277 children with non-11q23/KMT2A-rearranged AML were analyzed using publicly accessible next-generation sequencing data from Therapeutically Applicable Research to Generate Effective Treatments (TARGET) dataset. RESULTS: Pediatric AML patients with 11q23/KMT2A-rearrangements harbored a low number of mutations (Median, 1 mutation/patient, range, 1-22), 58% of which involved in RAS pathway mutations (KRAS, NRAS, and PTPN11) and 10.5% of which comprised of SETD2 mutations. Compared with non-11q23/KMT2A-rearranged AML, the incidence of KRAS (32.4% vs. 10.1%, P〈0.001) and SETD2 (10.5% vs. 1.4%, P=0.001) gene mutations in 11q23/KMT2A-rearranged AML was significantly higher. Both KRAS and SETD2 mutations occurred more often in t(10;11)(p12;q23). KRAS mutations were correlated with worse 5-year event-free survival [EFS] (Plog-rank = 0.001) and 5-year overall survival [OS] (Plog-rank = 0.009) and the presence of SETD2 mutations increases the 5-year relapse rate (PGray = 0.004). Multivariate analyses confirmed KRAS mutations in 11q23/KMT2A-rearranged AML as an independent predictor for poor EFS (hazard ratio [HR] = 2.10, P=0.05) and OS (HR = 2.39, P=0.054). CONCLUSION: Our findings show that pediatric patients with 11q23/KMT2A rearrangements have characteristic mutation patterns and varying clinical outcomes depending on different translocation partners, which could be utilized to develop more accurate risk stratification and tailored therapies.

[Clinical Analysis of Pediatric Acute Leukemia Complicated with Septic Shock].

OBJECTIVE: To analyze the clinical characteristics of predictors in pediatric acute leukemia complicated with septic shock and explore the prognostic factors. METHODS: The clinical characteristics of 70 children with acute leukemia and complicated with septic shock hospitalized in Sun Yat-sen Memorial Hospital from March 2012 to March 2021 were retrospectively analyzed. The clinical characteristics of patients in survival group and death group were analyzed and compared. Multiple logistic regression was used to test for predictors of death. RESULTS: Among the 70 children, 41 were males and 29 were females, with a median age of 7.0 (1.0-15.0) years old. 81.4% were hospital acquired infections. The pathogens were mostly Gram-negative bacteria (50/66, 75.8%) and the clinical manifestations were cold shock. Mortality rate was 34.3% (24/70). The length of hospitalization, duration of fever and antibiotic exposure longevity before the onset of septic shock were significantly different between survival group and death group. At septic shock onset, compared with the survival group, patients in the death group were younger, had lower platelet counts and higher levels of C-reactive protein and procalcitonin, and were more likely to have acute heart failure and more mechanical ventilation (all p<0.05). The results of multivariable analysis showed that mortality was independently associated with pediatric sequential organ failure assessment score (pSOFA) (odds ratio: 1.616, 95% CI: 1.160-2.251, p=0.005) and acute heart failure (odds ratio: 18.308, 95% CI: 1.939-172.911, p=0.011). In addition, the ROC curve analysis showed that pSOFA score had AUC of 0.8551 (95% CI: 0.7607-0.9495, p<0.001) predicting PICU mortality and its best predictive value was >9.5 (sensitivity 75.0%, specificity 87.0%). CONCLUSION: Pediatric acute leukemia complicated with septic shock is characterized as rapid deterioration and high mortality. A pSOFA score greater than 9.5 and acute heart failure are associated with poor outcomes.

Prognostic value and outcome for acute lymphocytic leukemia in children with MLL rearrangement: a case-control study.

PURPOSE: To evaluate the prognostic factors and outcome for acute lymphoblastic leukemia (ALL) in children with MLL rearrangement (MLL-r). METHODS: A total of 124 pediatric patients who were diagnosed with ALL were classified into two groups based on the MLL-r status by using a retrospective case-control study method from June 2008 to June 2020. RESULTS: The prevalence of MLL-r positive in the whole cohort was 4.9%. The complete remission (CR) rate on Day 33 in the MLL-r positive group was not statistically different from the negative group (96.8% vs 97.8%, P = 0.736). Multivariate analysis showed that T-cell, white blood cell counts (WBC) ≥ 50 × 109/L, MLL-AF4, and D15 minimal residual disease (MRD) positive were independent risk factors affecting the prognosis of MLL-r positive children. Stem cell transplantation (SCT) was a favorable independent prognostic factor affecting event-free survival (EFS) in MLL-r positive patients (P = 0.027), and there was a trend toward an independent prognostic effect on overall survival (OS) (P = 0.065). The 10-year predicted EFS for patients with MLL-AF4, MLL-PTD, MLL-ENL, other MLL partner genes, and MLL-r negative cases were 46.67 ± 28.61%, 85.71 ± 22.37%, 75 ± 32.41%, 75 ± 32.41%, and 77.33 ± 10.81%, respectively (P = 0.048). The 10-year predicted OS were 46.67 ± 28.61%, 85.71 ± 22.37%, 75 ± 32.41%, 75 ± 32.41%, and 85.2 ± 9.77%, respectively (P = 0.049). The 124 patients with ALL were followed up and eventually 5 (4%) cases relapsed, with a median relapse time of 3.9 years. CONCLUSION: Patients with MLL-r positive ALL have moderate remission rates, but are prone to relapse with low overall survival. The outcome of MLL-r positive ALL was closely related to the partner genes, and clinical attention should be paid to screening for MLL partner genes and combining them with other prognostic factors for accurate risk stratification.

Impact of posttransplant cyclophosphamide on the outcome of patients undergoing unrelated single-unit umbilical cord blood transplantation for pediatric acute leukemia.

BACKGROUND: Umbilical cord blood transplantation (UCBT) from unrelated donors is one of the successful treatments for acute leukemia in childhood. The most frequent side effect of UCBT is peri-engraftment syndrome (PES), which is directly associated with the greater prevalence of acute and chronic graft-versus-host-disease (aGvHD and cGvHD). In haploidentical stem cell transplantation, posttransplant cyclophosphamide (PTCY) has been demonstrated to be an effective method against GvHD. However, the effects of PTCY as a GvHD prophylactic in UCBT had not been investigated. This study aimed to evaluate the effects of PTCY on the outcomes of UCBT for pediatric acute leukemia. METHODS: This retrospective study included 52 children with acute leukemia who underwent unrelated single-unit UCBT after myeloablative conditioning regimens. The results from the PTCY and non-PTCY groups were compared. RESULTS: The incidence of transplantation-related mortality in non-PTCY and PTCY were 5% and 10% (p = 0.525), respectively. The incidence of relapse in non-PTCY and PTCY were 5% and 23% (p = 0.095), respectively. Second complete remission status (CR2) was an independent risk factor for relapse-free survival (hazard ratio = 9.782, p = 0.001). The odds ratio for sepsis or bacteremia incidence was significantly greater in the PTCY group (9.524, p = 0.017). PTCY group had increased rates of cytomegalovirus activity and fungal infection. The incidence of PES, aGvHD, cGvHD, and hemorrhagic cystitis in the PTCY group was lower than that in the non-PTCY group, although it was not significantly different. Additionally, higher doses of PTCY (29 mg/kg and 40 mg/kg) were associated with lower incidences of aGvHD and severe GvHD (65% and 29%, respectively) than lower doses (93% and 57%, respectively). Engraftment time and graft failure incidence were similar across groups. CONCLUSION: The results support the safety and efficiency of PTCY as part of PES controlling and GvHD prophylaxis in single-unit UCBT for children with acute leukemia. A PTCY dosage of 29 mg/kg to 40 mg/kg appears to be more effective in GvHD prophylaxis for UCBT patients.

Analysis of clinical characteristics and prognostic factors associated with EBV-associated HLH in children.

Purpose Our aim is to analyze the clinical characteristics and prognostic factors of Epstein-Barr (EB) virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) in children. Methods Children with newly diagnosed HLH were retrospectively analyzed. Results Finally, a total of 95 children with HLH were enrolled in this study, including 43 (45.3%) with EBV-HLH and 52 (54.7%) with non-EBV-HLH. Laboratory tests showed that the levels of absolute neutrophil count (ANC) decrease (P = 0.031) and triglycerides (TG) increase (P = 0.036) in the EBV-HLH group were statistically significant compared with those in the non-EBV-HLH group, respectively. We found that the remission rate during induction period in the EBV-HLH group and non-EBV-HLH group was 75.8% and 89.3%, respectively. The correlation analysis showed that the elevated degree of total bilirubin (TBIL) (P = 0.042), triglyceride (TG) (P = 0.009), serum ferritin (SF) (P = 0.008) and interleukin-8 (IL-8) (P = 0.004) were related with the remission rate during induction in the EBV-HLH group. Further univariate analysis showed that the elevated degree of TBIL (P = 0.048) and TG (P = 0.019) were significant risk factors for the remission rate during induction in the EBV-HLH group. In the multivariate analysis, we observed that there was statistical significance for the degree of TG elevation (P = 0.015) between the two groups. The correlation analysis showed that the elevated degree of TBIL (P = 0.030), the elevated degree of SF (P = 0.020) and the elevated degree of interleukin-6 (P = 0.010) were related to the induction mortality of children with EBV-HLH. Conclusion TBIL and TG are valid indicators to assess the efficacy and prognosis of EVBHLH among children in induction period.

[Clinical Characteristic, Diagnosis and Treatment of Acute Lymphoblastic Leukemia Combined with Pneumocystis Carinii Pneumonia in Children].

OBJECTIVE: To investigate the clinical characteristics and treatment of pneumocystis carinii pneumonia (PCP) in children with acute lymphoblastic leukemia (ALL), in order to improve the early diagnosis and effective treatment. METHODS: Clinical data of five children with ALL developing PCP in the post-chemotherapy granulocyte deficiency phase were analyzed retrospectively. The clinical manifestations, laboratory tests, imaging findings, treatment methods and effect were summarized. RESULTS: The male-to-female ratio of the five children was 1∶4, and the median age was 5.5 (2.9-8) years old. All patients developed PCP during granulocyte deficiency phase after induction remission chemotherapy. The clinical manifestations were generally non-specific, including high fever, tachypnea, dyspnea, non-severe cough, and rare rales in two lungs (wet rales in two patients). Laboratory tests showed elevated C-reactive protein (CRP), serum procalcitonin (PCT), (1,3)-ß-D-glucan (BDG), lactate dehydrogenase (LDH) and inflammatory factors including IL-2R, IL-6 and IL-8. Chest CT showed diffuse bilateral infiltrates with patchy hyperdense shadows. Pneumocystis carinii(PC) was detected in bronchoalveolar lavage fluid (BALF) or induced sputum by high-throughput sequencing in all patients. When PCP was suspected, chemotherapy was discontinued immediately, treatment of trimethoprim-sulfame thoxazole (TMP-SMX) combined with caspofungin against PC was started, and adjunctive methylprednisolone was used. Meanwhile, granulocyte-stimulating factor and gammaglobulin were given as the supportive treatment. All patients were transferred to PICU receiving mechanical ventilation due to respiratory distress during treatment. Four children were cured and one died. CONCLUSION: PCP should be highly suspected in ALL children with high fever, dyspnea, increased LDH and BDG, and diffuse patchy hyperdense shadow or solid changes in lung CT. The pathogen detection of respiratory specimens should be improved as soon as possible. TMP/SMZ is the first-line drug against PCP, and the combination of Caspofungin and TMP/SMZ treatment for NH-PCP may have a better efficacy. Patients with moderate and severe NH-PCP may benefit from glucocorticoid.

Umbilical cord blood: A promising source for allogeneic CAR-T cells.

Chimeric antigen receptor T (CAR-T) cell therapy is an effective treatment for relapsed and refractory acute lymphoblastic leukemia (R/R ALL). However, autologous CAR-T cells derived from patients with B-ALL often show poor amplification ability, exhaustion, and anergy. To overcome these limitations, allogeneic CAR-T cells may be used as effective substitutes; however, which source would be the best substitute is unclear. In this study, we compared the immunophenotype and antitumor efficacy of anti-CD19 CAR-T cells derived from healthy donor cord blood (CB), healthy donor peripheral blood (PB), and PB of B-ALL patients [PB (patient)] in vitro and NOD-Prkdcem26cd52Il2rgem26Cd22/Nju (NCG)-immunodeficient mice, respectively. The results revealed that CAR-T cells derived from healthy donor CB and PB showed a higher proportion of naive T cells and longer tumor suppression in tumor-bearing mice than those of PB (patient). PB (patient) CAR-T cells had a higher proportion of regulatory T cells (Treg cells) and released high levels of interluekin-10 (IL-10), which also suggest a poor prognosis. Thus, CAR-T cells derived from healthy donors have better antitumor efficacy than CAR-T cells derived from PB (patient), and CB may be a good source of allogeneic CAR-T cells.

Prognostic significance of CNSL at diagnosis of childhood B-cell acute lymphoblastic leukemia: A report from the South China Children's Leukemia Group.

Objectives: The prognostic significance of acute lymphoblastic leukemia (ALL) patients with central nervous system leukemia (CNSL) at diagnosis is controversial. We aimed to determine the impact of CNSL at diagnosis on the clinical outcomes of childhood B-cell ALL in the South China Children's Leukemia Group (SCCLG). Methods: A total of 1,872 childhood patients were recruited for the study between October 2016 and July 2021. The diagnosis of CNSL depends on primary cytological examination of cerebrospinal fluid, clinical manifestations, and imaging manifestations. Patients with CNSL at diagnosis received two additional courses of intrathecal triple injections during induction. Results: The frequency of CNLS at the diagnosis of B-cell ALL was 3.6%. Patients with CNSL at diagnosis had a significantly higher mean presenting leukocyte count (P = 0.002) and poorer treatment response (P <0.05) compared with non-CNSL patients. Moreover, CNSL status was associated with worse 3-year event-free survival (P = 0.030) and a higher risk of 3-year cumulative incidence of relapse (P = 0.008), while no impact was observed on 3-year overall survival (P = 0.837). Multivariate analysis revealed that CNSL status at diagnosis was an independent predictor with a higher cumulative incidence of relapse (hazard ratio = 2.809, P = 0.016). Conclusion: CNSL status remains an adverse prognostic factor in childhood B-cell ALL, indicating that additional augmentation of CNS-directed therapy is warranted for patients with CNSL at diagnosis.

Pneumocystis jirovecii-associated immune reconstitution inflammatory syndrome-like phenomenon in a child with leukaemia: a case report and literature review.

BACKGROUND: Immune reconstitution inflammatory syndrome (IRIS) refers to the phenomenon of intense immune responses against pathogens in patients with AIDS undergoing antiretroviral therapy to reconstitute immune function, resulting in functional impairment of multiple organs. Non-AIDS immunosuppressed hosts may also develop similar manifestations to IRIS during immune recovery. CASE PRESENTATION: An 8-year-old girl presented with acute lymphoblastic leukaemia was admitted for scheduled chemotherapy treatment. During chemotherapy, she experienced pancytopenia and Pneumocystis jirovecii pneumonia, which was diagnosed based on the abnormal shadows observed on chest computed tomography, the elevation of serum ß-D-glucan, and the positive mNGS results of Pneumocystis jirovecii in both sputum and blood. After treatment with Granulocyte Colony-Stimulating Factor, sulfamethoxazole, and caspofungin, aggravation of lung lesions was discovered and severe interstitial lung disease developed in a short period along with a rapidly increasing leukocyte count. Intravenous methylprednisolone pulse therapy was given, but lung function did not improve, and she finally died after the withdrawal of medical care. CONCLUSIONS: For patients with acute lymphocytic leukaemia infected with Pneumocystis jirovecii, the rapid aggravation of pulmonary lesions in the process of blood recovery and immune reconstitution should raise vigilance against the possibility of IRIS-like reactions. The use of granulocyte stimulating factors may aggravate the inflammatory response in the lungs. The timing, dosage, and duration of treatment of glucocorticoids and the impact of high-dose methylprednisolone pulse therapy on the prognosis of patients should be explored in further research.

Poor outcome of pediatric patients with acute myeloid leukemia harboring high FLT3/ITD allelic ratios.

Activating FLT3 mutations are the most common mutations in acute myeloid leukemia (AML), but the optimal threshold of FLT3/ITD allelic ratio (AR) among pediatric AML patients remains controversial. Here, we present the outcome and prognostic significance of FLT3/ITD AR analysis among pediatric patients with AML from the TARGET dataset. Applying fitting curve models and threshold effect analysis using the restrictive cubic spline function following Cox proportional hazards models identifies the cut-off value of 0.5 on FLT3/ITD AR. Moreover, we observe that high FLT3/ITD AR patients have an inferior outcome when compared to low AR patients. Our study also demonstrates that stem cell transplantation may improve the outcome in pediatric AML patients with high FLT3/ITD AR and may be further improved when combined with additional therapies such as Gemtuzumab Ozogamicin. These findings underline the importance of individualized treatment of pediatric AML.

A Nomogram for Predicting Event-Free Survival in Childhood Acute Lymphoblastic Leukemia: A Multicenter Retrospective Study.

Objective: Even though childhood acute lymphoblastic leukemia (ALL) has an encouraging survival rate in recent years, some patients are still at risk of relapse or even death. Therefore, we aimed to construct a nomogram to predict event-free survival (EFS) in patients with ALL. Method: Children with newly diagnosed ALL between October 2016 and July 2021 from 18 hospitals participating in the South China children's leukemia Group (SCCLG) were recruited and randomly classified into two subsets in a 7:3 ratio (training set, n=1187; validation set, n=506). Least absolute shrinkage and selection operator (LASSO) and multivariate Cox regression analysis were adopted to screen independent prognostic factors. Then, a nomogram can be build based on these prognostic factors to predict 1-, 2-, and 3-year EFS. Concordance index (C-index), area under the curve (AUC), calibration curve, and decision curve analysis (DCA) were used to evaluate the performance and clinical utility of nomogram. Result: The parameters that predicted EFS were age at diagnosis, white blood cell at diagnosis, immunophenotype, ETV6-RUNX1/TEL-AML1 gene fusion, bone marrow remission at day 15, and minimal residual disease at day 15. The nomogram incorporated the six factors and provided C-index values of 0.811 [95% confidence interval (CI) = 0.792-0.830] and 0.797 (95% CI = 0.769-0.825) in the training and validation set, respectively. The calibration curve and AUC revealed that the nomogram had good ability to predict 1-, 2-, and 3-year EFS. DCA also indicated that our nomogram had good clinical utility. Kaplan-Meier analysis showed that EFS in the different risk groups stratified by the nomogram scores was significant differentiated. Conclusion: The nomogram for predicting EFS of children with ALL has good performance and clinical utility. The model could help clinical decision-making.

CEBPA are independent good prognostic factors in pediatric acute myeloid leukemia.

To evaluate the outcome and prognostic significance of CEBPA mutations among pediatric acute myeloid leukemia (AML) from TARGET dataset. A total of 1803 pediatric patients who were diagnosed with AML were classified into two groups based on the CEBPA status by using a retrospective cohort study method from September 1996 to December 2016. The incidence of CEBPA mutations was 18%. CEBPA mutations were significantly associated with elder age (p < 0.001), higher WBC (p = 0.004), higher proportion of peripheral blood blast (p < 0.001), normal karyotype (p < 0.001), low risk (p < 0.001) and higher complete remission induction rates (p < 0.05). Overall, CEBPA mutations patients had a significantly better 5-year EFS (p < 0.001) and OS (p < 0.001) compared to CEBPA wild-type patients, and this favorable impact was maintained even in the presence of FLT3/ITD mutations. Stem cell transplantation had no significant impact on the survival of patients with coexistence of CEBPA and FLT3/ITD mutations. Multivariate analysis demonstrated that mutated CEBPA were an independent favorable indicators of better outcome in terms of EFS (p = 0.007) and OS (p = 0.039). Our study demonstrate mutated CEBPA have an excellent outcome in pediatric AML patients. Furthermore, pediatric AML patients with coexistence of CEBPA and FLT3/ITD mutation appear to have favorable prognoses and might not required stem cell transplantation.

[Efficacy of Posaconazole for Primary Prophylaxis in the Induction Therapy of Childhood Acute Lymphoblastic Leukemia].

OBJECTIVE: To explore the effect of posaconazole in the primary prevention of invasive fungal disease (IFD) in the induction therapy of childhood acute lymphoblastic leukemia (ALL). METHODS: From August 2018 to November 2020, 144 pediatric patients with ALL treated in Department of Pediatrics, Sun Yat-Sen Memorial Hospital, Sun Yat-Sen University were selected, 88 cases received fluconazole as IFD prophylaxis (fluconazole prophylaxis group), 56 cases received posaconazole as IFD prophylaxis (posaconazole prophylaxis group). The incidence of IFD and treatment-related adverse reactions between the two groups were compared, and the safety of posaconazole was evaluated. RESULTS: The incidence of IFD in the fluconazole prophylaxis group was 20.4% (18/88), and in the posaconazole prophylaxis group was 7.1% (4/56). The incidence of IFD between the two groups was statistically significant different(P=0.030). There was no serious adverse reactions in the two groups. The incidence of mild adverse reactions in the posaconazole prophylaxis group (23.2%) was lower than that in the fluconazole prophylaxis group(39.8%), and the difference was statistically significant (P=0.039). There were 12 cases died in the fluconazole prophylaxis group and 4 in the posaconazole prophylaxis group, while no significant difference in the overall survival rate between the two groups (P=0.281). CONCLUSION: The effect of posaconazole in the primary prophylaxis of IFD is better and incidence of adverse reactions is lower than fluconazole. Posaconazole can be tolerated, and expected to become the first-line primary prophylaxis drug for IFD during the induction remission therapy of childhood ALL.