Phase II/III study in children and adolescents with newly diagnosed B-cell precursor acute lymphoblastic leukemia: protocol for a nationwide multicenter trial in Japan

Delayed diagnostic interval and survival outcomes in pediatric leukemia: A single-center, retrospective study

OBJECTIVE

This study primarily focused on the diagnostic interval (DI), defined as the duration from the onset of leukemic symptoms to diagnosis. We investigated whether a prolonged DI is associated with the outcomes of pediatric leukemia.

METHODS

We retrospectively collected data of children with newly diagnosed pediatric leukemia at Okayama University Hospital from January 2007 to December 2022. Survival analyses were conducted using Kaplan-Meier methods, and an unadjusted analysis to compare differences in survival was performed using the log-rank test.

RESULTS

In total, 103 children with leukemia were included in the analysis. The median DI was 20 days (interquartile range, 9.5-33.5 days). A prolonged DI (≥30 days) demonstrated no association with either 5-year event-free survival (70.1% for <30 days and 68.3% for ≥30 days, p = .99, log-rank test) or overall survival (84.7% for <30 days and 89.4% for ≥30 days, p = .85, log-rank test).

CONCLUSIONS

A prolonged DI was not associated with the survival of children with leukemia. If a precise classification of leukemia biology is provided for pediatric patients, a prolonged DI may have little impact on the prognosis of these patients.

Genome-wide assessment of genetic risk loci for childhood acute lymphoblastic leukemia in Japanese patients

Not available.

Analysis of non-alcoholic fatty liver disease during induction therapy for B-cell precursor acute lymphoblastic leukemia in children and adolescents

BACKGROUND

A prospective evaluation of non-alcoholic fatty liver disease (NAFLD) during induction therapy for acute lymphoblastic leukemia (ALL) has not been performed. Herein, we prospectively investigated the frequency, risk factors, and outcomes of NAFLD during induction therapy in children and adolescents with B-cell precursor ALL (BCP-ALL).

METHODS

This study enrolled 74 newly diagnosed BCP-ALL cases aged 1 year and older who were admitted to our department between January 2011 and December 2020. Median age was 6.6 years (1.3-17.5 years). Plain computed tomography (CT) of the upper abdomen was performed before induction therapy, and on days 15 and 29 after initiation of induction therapy. Patients with a liver/spleen CT ratio <0.9 were defined as having NAFLD.

RESULTS

The frequency of NAFLD was 73%. Patients with NAFLD had a higher rate of hypertriglyceridemia. There was no significant difference in 5-year overall survival and event-free survival (EFS) between patients with and without NAFLD. However, after restricting the target age to 10 years and older, 5-year EFS was significantly higher in patients with NAFLD than in those without (88.5 vs. 42.9%, respectively, P = 0.037). Similarly, 5-year cumulative incidence of relapse (CIR) was significantly lower in patients with NAFLD than in those without it (5-year CIR, 6.3 vs. 57.1%, respectively, P = 0.013).

CONCLUSION

Patients with NAFLD exhibit better outcomes including 5-year EFS and CIR. Further studies are necessary.

Current Challenges of Asian National Children's Cancer Study Groups on Behalf of Asian Pediatric Hematology and Oncology Group

In Asia, a few countries have a long and established history of collaborative clinical trials successfully formed national children's cancer study groups, but many still do not have such groups. The process of forming national children's cancer groups is fraught with many hurdles, which varies among the countries. One of the basic requirements for running clinical trials is an affordable health care system in which most of the children with cancer can receive the proposed treatment. The health insurance coverage for children with cancer varies from <20% to as high as 100% among Asian countries, and the operation of clinical trials must also be adjusted accordingly. Shortage of research personnel is common, including medical, nursing, research coordinators, and data managers. The establishment of the Asian Pediatric Hematology and Oncology Group aims to provide a good platform for promotion of international clinical trials in the Asian countries.

Remission, treatment failure, and relapse in pediatric ALL: an international consensus of the Ponte-di-Legno Consortium

Comparison of treatment strategies in de novo pediatric acute lymphoblastic leukemia (ALL) requires standardized measures of efficacy. Key parameters that define disease-related events, including complete remission (CR), treatment failure (TF; not achieving CR), and relapse (loss of CR) require an updated consensus incorporating modern diagnostics. We collected the definitions of CR, TF, and relapse from recent and current pediatric clinical trials for the treatment of ALL, including the key components of response evaluation (timing, anatomic sites, detection methods, and thresholds) and found significant heterogeneity, most notably in the definition of TF. Representatives of the major international ALL clinical trial groups convened to establish consensus definitions. CR should be defined at a time point no earlier than at the end of induction and should include the reduction of blasts below a specific threshold in bone marrow and extramedullary sites, incorporating minimal residual disease (MRD) techniques for marrow evaluations. TF should be defined as failure to achieve CR by a prespecified time point in therapy. Relapse can only be defined in patients who have achieved CR and must include a specific threshold of leukemic cells in the bone marrow confirmed by MRD, the detection of central nervous system leukemia, or documentation of extramedullary disease. Definitions of TF and relapse should harmonize with eligibility criteria for clinical trials in relapsed/refractory ALL. These consensus definitions will enhance the ability to compare outcomes across pediatric ALL trials and facilitate development of future international collaborative trials.

Successful hematopoietic stem cell transplantation for two patients with relapse of intrachromosomal amplification of chromosome 21-positive B-cell precursor acute lymphoblastic leukemia

In children with relapsed acute lymphoblastic leukemia (ALL), it is essential to identify patients in need of treatment intensification. Minimal residual disease (MRD)-based treatment stratification resulted in excellent survival in children with late relapsed B-cell precursor (BCP)-ALL. Chemotherapy alone produced a favorable outcome in patients with negative MRD after induction. The genetic abnormality also plays an important role in determining the prognosis and stratification for treatment. Intrachromosomal amplification of chromosome 21 (iAMP21) is associated with a poor outcome and a high risk for relapse, and there is no standard treatment after relapse. Herein, we present two patients with relapsed iAMP21-positive ALL who were successfully treated by cord blood transplantation (CBT). Although both patients had late bone marrow relapse and favorable MRD response, CBT was performed due to iAMP21 positive. Patients 1 and 2 have been in remission post-CBT for 15 and 45 months, respectively. Patients with relapsed iAMP21-positive ALL may be considered for stem cell transplantation even in late relapses and favorable MRD response.

Association of Multiple Gene Polymorphisms Including Homozygous NUDT15 R139C With Thiopurine Intolerance During the Treatment of Acute Lymphoblastic Leukemia

Although thiopurine is a crucial drug for treating acute lymphoblastic leukemia, individual variations in intolerance are observed due to gene polymorphisms. A 3-year-old boy with B-cell precursor acute lymphoblastic leukemia who was administered thiopurine developed mucositis, sepsis, and hemophagocytic lymphohistiocytosis due to prolonged hematologic toxicity, chronic disseminated candidiasis, and infective endocarditis that triggered multiple brain infarctions. The patient was found to harbor 3 gene polymorphisms associated with thiopurine intolerance including homozygous NUDT15 R139C, heterozygous ITPA C94A, and homozygous MTHFR C677T and heterozygous RFC1 G80A. Thus, the combined effect of intolerance via multiple gene polymorphisms should be considered in case of unexpected adverse reactions.

Lymphomatoid Papulosis Development in Acute Lymphoblastic Leukemia

Lymphomatoid papulosis (LyP) is a chronic, recurrent benign skin disease characterized by histological features of a CD 30-positive cutaneous T-cell lymphoproliferative disorder. It is rare, with an annual, worldwide incidence of 1.2 - 1.9 per million, and accounts for 16-47% of pediatric cutaneous lymphoproliferative disorders. It often occurs on the extremities or the trunk and rarely affects the face or genitals. Its onset may be triggered by irradiation therapy, immunomodulating agents, infection or atopic dermatitis. It has a benign course but is associated with certain hematological malignancies. Mycosis fungoides and primary cutaneous anaplastic large cell lymphoma are the most commonly associated hematological malignancies. The incidence of lymphoma in children with LyP has been reported to be 8.5% at most. Most patients who develop lymphomas do so within 4 years of the LyP onset; therefore, patients with LyP should be carefully followed up. Herein, we report a case in which tumors appeared in the left scrotum and under the left lip during maintenance therapy for precursor B-cell acute lymphoblastic leukemia. We needed to distinguish the tumor from extramedullary recurrence of ALL or de novo other cutaneous lymphoma; however, the histological findings of a tumor biopsy resulted in a diagnosis of LyP.

In-Hospital Management Might Reduce Induction Deaths in Pediatric Patients With Acute Lymphoblastic Leukemia: Results From a Japanese Cohort

Induction deaths (ID) remain a critical issue in the treatment of pediatric patients with acute lymphoblastic leukemia (ALL). The reported rate of ID in this population is 1% or higher. We speculate that this proportion might be lower in Japan because of mandatory hospitalization during induction therapy to manage complications. We retrospectively analyzed the incidence of ID among children with ALL enrolled in 4 Japanese study groups between 1994 and 2013. Among 5620 children, 41 (0.73%) cases of ID were noted. The median age was 6.5 years; 24 children were female, and 7 had T-cell ALL. Infection was the most common cause of ID (n=22), but the incidence (0.39%) was lower than that reported in western countries. Mortality within 48 hours from the onset of infection was low, comprising 25% of infection-related deaths. The incidence of infections caused by Bacillus species was low. Only 1 patient died because of Aspergillus infection. Fatal infections mostly occurred during the third week of induction therapy. Our findings suggest that close monitoring, stringent infection control, and immediate administration of appropriate antibiotics through hospitalization might be important strategies in reducing the rate of infection-related ID in pediatric patients with ALL.

Trends in survival of leukemia among children, adolescents, and young adults: A population-based study in Osaka, Japan

This study focused on children as well as adolescents and young adults (AYAs) and aimed to examine trends in survival of leukemia over time using population-based cancer registry data from Osaka, Japan. The study subjects comprised 2254 children (0-14 years) and 2,905 AYAs (15-39 years) who were diagnosed with leukemia during 1975-2011. Leukemia was divided into four types: acute lymphoblastic leukemia (ALL), acute myeloid leukemia (AML), chronic myeloid leukemia (CML), and other leukemias. We analyzed 5-year overall survival probability (5y-OS), using the Kaplan-Meier method and expressed time trends using the joinpoint regression model. For recently diagnosed (2006-2011) patients, a Cox proportional hazards model was applied to determine predictors of 5y-OS, using age group, gender, and treatment hospital as covariates. Over the 37-year period, 5y-OS greatly improved among both children and AYAs, for each leukemia type. Among AYAs, 5y-OS of ALL improved, especially after 2000 (65% in 2006-2011), when the pediatric regimen was introduced but was still lower than that among children (87% in 2006-2011, P < .001). Survival improvement was most remarkable in CML, and its 5y-OS was over 90% among both children and AYAs after the introduction of molecularly targeted therapy with tyrosine kinase inhibitors. Among patients with recently diagnosed AML, the risk of death was significantly higher for patients treated at nondesignated hospitals than those treated at designated cancer care hospitals. The changes in survival improvement coincided with the introduction of treatment regimens or molecularly targeted therapies. Patient centralization might be one option which would improve survival.

Comparison of child and family reports of health-related quality of life in pediatric acute lymphoblastic leukemia patients after induction therapy

BACKGROUND

This study aims at determining the health-related quality of life (HRQOL) of children with acute lymphoblastic leukemia (ALL) after the induction therapy, assessing the agreement between child self-reports and family proxy-reports HRQOL, and determining the factors related to this agreement, especially child age, family attendance, and children's social relationships beyond the family.

METHODS

We analyzed questionnaire data (2012-2017) from the Japanese Pediatric Leukemia/Lymphoma Study Group's clinical study (ALL-B12). Participants were children with B-cell precursor ALL aged 5-18 and their family members, who mostly took care of the child during hospitalization. Participants answered the Pediatric Quality of Life Inventory™ (PedsQL™) Generic Core Scales (PedsQL-G), and Cancer Module (PedsQL-C) to measure pediatric HRQOL. We calculated the differences between child self-reported and family proxy-reported subscale scores along with intraclass correlation coefficients (ICC). We conducted multiple regression analyses according to all participant pairs and age groups (young children, school age, and adolescents), with ICCs for all PedsQL-G subscales (ICC-G) and all PedsQL-C subscales (ICC-C) as the outcome variables.

RESULTS

Five hundred twenty-two pairs of children and their families were analyzed. We observed a moderate level of agreement on most PedsQL subscales between child self-reports and family proxy-reports; however, worry had the weakest agreement for all PedsQL subscales (ICC = .32, 95% confidence interval = .24-.40). The agreement of ICC-C was positively related to family attendance in the hospitalization, only for the young children group (B = .185, p = .003).

CONCLUSIONS

We observed some differences between child self-reports and family proxy-reports of HRQOL of children with ALL. Both child self-reports and family proxy-reports captured HRQOL in the induction therapy. We suggest that attending to young children's hospitalization affects the level of agreement between reports on their HRQOL.

Risk-adjusted therapy for pediatric non-T cell ALL improves outcomes for standard risk patients: results of JACLS ALL-02

This study was a second multicenter trial on childhood ALL by the Japan Childhood Leukemia Study Group (JACLS) to improve outcomes in non-T ALL. Between April 2002 and March 2008, 1138 children with non-T ALL were enrolled in the JACLS ALL-02 trial. Patients were stratified into three groups using age, white blood cell count, unfavorable genetic abnormalities, and treatment response: standard risk (SR), high risk (HR), and extremely high risk (ER). Prophylactic cranial radiation therapy (PCRT) was abolished except for CNS leukemia. Four-year event-free survival (4yr-EFS) and 4-year overall survival (4yr-OS) rates for all patients were 85.4% ± 1.1% and 91.2% ± 0.9%, respectively. Risk-adjusted therapy resulted in 4yr-EFS rates of 90.4% ± 1.4% for SR, 84.9% ± 1.6% for HR, and 66.5% ± 4.0% for ER. Based on NCI risk classification, 4yr-EFS rates were 88.2% in NCI-SR and 76.4% in NCI-HR patients, respectively. Compared to previous trial ALL-97, 4yr-EFS of NCI-SR patients was significantly improved (88.2% vs 81.2%, log rank p = 0.0004). The 4-year cumulative incidence of isolated (0.9%) and total (1.5%) CNS relapse were significantly lower than those reported previously. In conclusion, improved EFS in NCI-SR patients and abolish of PCRT was achieved in ALL-02.

Efficacy and safety of tisagenlecleucel in Japanese pediatric and young adult patients with relapsed/refractory B cell acute lymphoblastic leukemia

Tisagenlecleucel is an autologous T cell genetically modified ex vivo using a lentiviral vector encoding an anti-CD19 chimeric antigen receptor. Here, we present the efficacy and safety of tisagenlecleucel in a subgroup of Japanese patients with relapsed/refractory (r/r) B-cell acute lymphoblastic leukemia (ALL). ELIANA was a single-arm, open-label, multicenter, phase 2 study. Patients were aged ≥ 3 years at screening to ≤ 21 years at the time of diagnosis, and had ≥ 5% lymphoblasts in bone marrow at screening. Primary endpoint was overall remission rate [ORR; complete remission (CR) + CR with incomplete blood recovery (CRi)] within 3 months after infusion. As of April 13, 2018, eight patients were enrolled and six had been infused. ORR was 66.7% (95% confidence interval 22.3-95.7); three patients achieved CR and one patient had CRi. All patients with CR/CRi were negative for minimal residual disease. One patient had CR/CRi lasting 19.5 + months. Cytokine release syndrome (CRS) and neurological events occurred in 83% and 17% of patients, respectively. CRS resolved with anti-cytokine therapy and supportive care. Two deaths occurred due to disease progression. No cases of cerebral edema were observed. Tisagenlecleucel produced high remission rates and durable responses offering a new treatment option for Japanese pediatric and young adults with r/r B-ALL.