Rare TCF3 variants associated with pediatric B cell acute lymphoblastic leukemia.

Germline genetic variants influence development of pediatric B cell acute lymphoblastic leukemia (B-ALL). Genome-wide association studies (GWAS) have identified several pediatric B-ALL susceptibility loci. IKZF1 and PAX5, transcription factors involved in B cell development, have been reported as susceptibility genes for B-ALL development. Therefore, we hypothesized that rare variants of genes involved in B cell development would be candidate susceptibility loci for pediatric B-ALL. Thus, we sequenced TCF3, a key transcription factor gene involving in B cell development. Saliva DNA from 527 pediatric patients with pediatric B-ALL in remission who were registered with the Tokyo Children's Cancer Study Group (TCCSG) were examined. As a TCF3 gene-based evaluation, the numbers of rare deleterious germline TCF3 sequence variants in patients with pediatric B-ALL were compared with those in cancer-free individuals using data in public databases. As a TCF3 single-variant evaluation, the frequencies of rare deleterious germline TCF3 sequence variants in patients with pediatric B-ALL were also compared with those in control data. TCF3 gene-based analysis revealed significant associations between rare deleterious variants and pediatric B-ALL development. In addition, TCF3 variant-based analysis showed particularly strong association between variant rs372168347 (three in 521 TCCSG and three in the 15780 gnomAD whole genome analysis cohort, p = 0.0006) and pediatric B-ALL development. TCF3 variants are known to influence B cell maturation and may increase the risk of preleukemic clone emergence.

Preemptive hematopoietic cell transplantation for asymptomatic patients with X-linked lymphoproliferative syndrome type 1.

Few reports have examined whether prophylactic allogeneic hematopoietic cell transplantation (HCT) for X-linked lymphoproliferative syndrome type 1 (XLP1) improves the prognosis. We compared the prognosis of symptomatic probands and affected siblings in the same family. Twenty-two cases (10 probands and 12 affected siblings) in Japan, the United Kingdom, and the United States were analyzed. The overall survival (OS) rate at 5 years after diagnosis was 70.0% in probands and 91.7% in affected siblings (p = 0.0789). The prognosis of patients who developed symptoms of XLP1 before HCT and those who did not was also compared. The 5-year probability of OS from the time of diagnosis in asymptomatic patients (100%) was significantly better than that in symptomatic patients (66.7%). These results suggested that early HCT as soon as the diagnosis is made improves the prognosis in asymptomatic XLP1 patients.

Effect of Germline MEFV Polymorphisms on the Prognosis of Japanese Children with Cancer: A Regional Analysis.

INTRODUCTION: MEFV is the gene responsible for familial Mediterranean fever. It encodes pyrin, which controls inflammation. Besides, previous studies have reported that some germline MEFV variants were associated with tumour susceptibility. MATERIALS AND METHODS: The loci of 12 germline MEFV variants were genotyped in 153 Japanese children with cancer, and the frequencies of these variants among the patient groups were compared with those in the general Japanese population. Additionally, the relationship between these variants and clinical data, including relapse and death, was investigated. RESULTS: Minor allele frequencies did not differ between patients and the general population, or between sex, age at diagnosis, and diagnosis among patients. P369S/R408Q associated with significantly lower relapse-free survival in all patient analyses and in patients with solid tumours. Additionally, although the results were not significant, E148Q/L110P was likely to associate with worse relapse-free survival in patients with solid tumours. DISCUSSION/CONCLUSION: Despite several limitations, this study provided the novel insight that the germline MEFV variants are associated with the clinical outcome of paediatric cancer.

Distinct clonal evolution in a case with anaplastic embryonal rhabdomyosarcoma.

BACKGROUND: Clonal evolution of malignancy is a complex process related to intratumoral heterogeneity, as recent studies have also demonstrated in rhabdomyosarcoma. The purpose of this study is to present a distinct clonal feature of a case with anaplastic embryonal type rhabdomyosarcoma (ERMS) using molecular analysis. METHODS: A five-year-old girl developed a metastatic pelvic tumor. We cultured neoplastic cells isolated from the biopsy sample. Next, to characterize the current case, we analyzed the biopsy sample, autopsy sample, and established cell line using combined modalities, including histopathological, cytogenetic, and molecular assay. We also undertook the backtrack mutation-specific polymerase chain reaction to reveal clonal composition. RESULTS: The histology of the biopsy sample was consistent with ERMS with focal anaplasia. We established a permanently growing cell line, ICH-ERMS-1, from the biopsy sample. On molecular analysis, the biopsied tissue revealed a missense mutation at codon 245 of TP53. In contrast, the autopsy tumor tissue and the cell line established from the biopsied tissue showed a missense mutation at codon 248. A backtrack study using mutation-specific polymerase chain reaction detected a TP53 codon 248 mutation in the original biopsy sample. All the specimens examined had a missense mutation at PTPN11 codon 69. CONCLUSIONS: This study highlights intratumoral heterogeneity and distinct clonal change related to the functional context in our anaplastic ERMS case, supporting the concept of intratumoral heterogeneity and clonal evolution. It requires further case collection to reveal whether p14ARF-p53-MDM2 tumor suppressor pathway alteration, considered a late event in ERMS tumorigenesis, is responsible for anaplasia in ERMS.

Haploidentical peripheral blood stem cell transplantation without irradiation or busulfan after reduced-intensity conditioning for KMT2A(MLL)-rearranged infant B-cell precursor acute lymphoblastic leukemia: Report of two cases.

We present two infants with KMT2A(MLL)-gene-R-associated BCP-ALL, who received HLA haploidentical PBSCT after RIC. The patients developed ALL at age 6 months and 3 months, respectively. Case 1 underwent PBSCT at the second CR with detectable KMT2A-AFF1(MLL-AF4) fusion gene transcript at 11 months of age, and Case 2 at the first CR without KMT2A-MLLT1(MLL-ENL) fusion gene transcript at 8 months of age. Both patients received G-CSF-mobilized unmanipulated peripheral blood mononuclear cells from their HLA haploidentical mothers after administration of FLU, MEL, and ATG. Tacrolimus, methotrexate, and mPSL were administered as prophylaxis against GVHD. Engraftment was rapidly obtained with complete chimerism in both patients. Acute adverse events included acute GVHD in Case 1 and bacterial sepsis in Case 2. At last clinical check at age 5 years and 4 years, respectively, both patients were recurrence-free and attained normal growth and development. We conclude that PBSCT from an HLA haploidentical mother with non-TBI and non-BU regimen seems feasible and efficacious, offering favorable life quality for infants.

High event-free survival rate with minimum-dose-anthracycline treatment in childhood acute promyelocytic leukaemia: a nationwide prospective study by the Japanese Paediatric Leukaemia/Lymphoma Study Group.

We evaluated the efficacy of treatment using reduced cumulative doses of anthracyclines in children with acute promyelocytic leukaemia (APL) in the Japanese Paediatric Leukaemia/Lymphoma Study Group AML-P05 study. All patients received two and three subsequent courses of induction and consolidation chemotherapy respectively, consisting of all-trans retinoic acid (ATRA), cytarabine and anthracyclines, followed by maintenance therapy with ATRA. Notably, a single administration of anthracyclines was introduced in the second induction and all consolidation therapies to minimize total doses of anthracycline. The 3-year event-free (EFS) and overall survival rates for 43 eligible children were 83·6% [95% confidence interval (CI): 68·6-91·8%] and 90·7% (95% CI: 77·1-96·4%), respectively. Although two patients died of intracranial haemorrhage or infection during induction phases, no cardiac adverse events or treatment-related deaths were observed during subsequent phases. Patients not displaying M1 marrow after the first induction therapy, or those under 5 years of age at diagnosis, showed inferior outcomes (3-year EFS rate; 33·3% (95% CI: 19·3-67·6%) and 54·6% (95% CI: 22·9-78·0%), respectively). In conclusion, a single administration of anthracycline during each consolidation phase was sufficient for treating childhood APL. In younger children, however, conventional ATRA and chemotherapy may be insufficient so that alternative therapies should be considered.

Genotyping NUDT15 can predict the dose reduction of 6-MP for children with acute lymphoblastic leukemia especially at a preschool age.

The pharmacokinetics among children has been altered dynamically. The difference between children and adults is caused by immaturity in things such as metabolic enzymes and transport proteins. The periods when these alterations happen vary from a few days to some years after birth. We hypothesized that the effect of gene polymorphisms associated with the dose of medicine could be influenced by age. In this study, we analyzed 51 patients with childhood acute lymphoblastic leukemia (ALL) retrospectively. We examined the associations between the polymorphism in NUDT15 and clinical data, especially the dose of 6-mercaptopurine (6-MP). Ten of the patients were heterozygous for the variant allele in NUDT15. In patients under 7 years old with NUDT15 variant allele, the average administered dose of 6-MP was lower than that for the patients homozygous for the wild-type allele (P=0.04). Genotyping of NUDT15 could be a beneficial to estimate the tolerated dose of 6-MP for patients with childhood ALL, especially at a preschool age in Japan. Furthermore, the analysis with stratification by age might be useful in pharmacogenomics among children.

Role of Second Transplantation for Children With Acute Myeloid Leukemia Following Posttransplantation Relapse.

BACKGROUND: In children with acute myeloid leukemia (AML), hematopoietic stem cell transplantation (HSCT) in first remission is indicated for patients with a relatively high risk of relapse. Second HSCT is a curative option; however, few reports have been published about a second HSCT in children for AML with posttransplantation relapse. PROCEDURE: Using the database provided by the Japanese Society of Hematopoietic Cell Transplantation, we analyzed 46 children with AML who underwent a second allogeneic HSCT after achieving a second remission. RESULTS: The median duration from the first to second HSCT was 20 months, and the source of the second HSCT was related bone marrow (BM) in 22, related peripheral blood in 6, unrelated BM in 14, and unrelated cord blood in 4 patients. Twenty-five children eventually died of the following causes: progressive disease in 14 and transplant-related toxicities in 9. The 5-year overall survival rate was 41.7 ± 7.7%. An interval of less than 24 months between the first and second HSCT was a significant poor prognostic factor. CONCLUSIONS: Children with AML who experience a relapse after HSCT in first remission have a good chance of survival with a second HSCT if a second remission is achieved.

Pharmacokinetics, efficacy, and safety of caspofungin in Japanese pediatric patients with invasive candidiasis and invasive aspergillosis.

The antifungal agents approved in Japan for pediatric use are limited and many unapproved drugs are actually used without clear instruction for dosage. We investigated the pharmacokinetics of caspofungin for the treatment of invasive candidiasis and invasive aspergillosis in 20 Japanese pediatric patients using a pediatric-specific dosage based on body surface area. Caspofungin was administered intravenously over 60 min as 70 mg/m(2) on Day 1, followed by 50 mg/m(2) per day. Five or 4 point blood sampling were done in 15 patients on Day 4-5 to calculate AUC0-24 h. The geometric means (95% confidence interval) of C24 h and AUC0-24 h in the pediatric patients were 3.3(2.5, 4.4) µg/mL and 175.1 (139.3, 220.1) µg hr/mL, respectively, which were comparable to those in Japanese adult patients [3.2 (2.8, 3.5) µg/mL and 144.9 (131.7, 159.3) µg hr/mL, respectively]. Among the 20 patients, 10 (50%) had at least 1 drug-related adverse event which was considered related to caspofungin therapy. No drug-related serious adverse event and no death occurred. The most common drug-related adverse events were events relating to hepatic function (mainly increases in ALT and AST). The overall success in efficacy was observed in 13 of 20 patients. In conclusion, once daily administration of caspofungin (70 mg/m(2) on Day 1, followed by 50 mg/m(2) [maximum daily dose not to exceed 70 mg]), which is the same dosage being used in overseas, achieved sufficient drug exposure and a favorable efficacy and acceptable safety profile in Japanese pediatric patients with invasive fungal infections.

Bullous pemphigoid after allogeneic hematopoietic stem cell transplantation.

Bullous pemphigoid (BP) is an autoimmune skin disorder characterized by subepidermal blisters due to deposit of autoantibody against dermal basement membrane protein. It has been reported that BP can occur after allogeneic hematopoietic stem cell transplantation (HSCT). We describe a patient with BP having autoantibody against BP180 after unrelated-donor HSCT against T lymphoblastic leukemia. The patient was treated with steroid leading to complete resolution of BP, but T lymphoblastic leukemia progressed rapidly after steroid hormone treatment. Given that immunosuppressant may reduce graft-versus-tumor effect, immunomodulatory agents such as nicotinamide and tetracycline, erythromycin, and immunoglobulin may be appropriate as soon as typical blister lesions are seen after HSCT.

Influence of SLCO1B1 polymorphism on maintenance therapy for childhood leukemia.

BACKGROUND: Management of the adverse effects of chemotherapy is essential to improve outcome of children with leukemia. Some genetic polymorphisms can predict treatment-related toxicity, and be used individually in dose modification of 6-mercaptopurine (6-MP) and methotrexate (MTX) in maintenance therapy for childhood acute lymphoblastic leukemia (ALL). We investigated associations between clinical course and candidate gene polymorphisms less evaluated in Japanese patients. METHODS: Fifty-three children who received maintenance chemotherapy were enrolled in this study. The scheduled dose of oral 6-MP was 40 mg/m(2) daily and that of oral MTX was 25 mg/m(2) weekly. The doses were adjusted according to white blood cell count (target range, 2.5-3.5 × 10(9) /L) and aspartate aminotransferase and alanine aminotransferase level (< 750 IU/L). Eight polymorphisms in six candidate genes, TPMT, ITPA, MRP4, MTHFR, RFC1, and SLCO1B1, were genotyped using the Taqman PCR method. Clinical course was reviewed retrospectively from medical records. RESULTS: The average dose of 6-MP was lower in the patients with at least one variant allele at SLCO1B1 c.521 T > C than in the patients with wild homozygous genotype. The other analyzed polymorphisms were not associated with toxicity, 6-MP, or MTX dose. CONCLUSIONS: Polymorphism of SLCO1B1 c.521 T > C could be a strong predictor of 6-MP dose reduction in maintenance chemotherapy in childhood ALL.

Reduced intensity conditioning in allogeneic stem cell transplantation for AML with Down syndrome.

Allogeneic hematopoietic stem cell transplantation (HSCT) has not been widely used in patients with acute myeloid leukemia (AML) and Down syndrome (DS) due to fear of transplantation-related toxicity. A retrospective analysis of the outcome of allogeneic HSCT was conducted in 15 patients with AML and DS. The five patients transplanted with the reduced intensity conditioning (4 in complete remission (CR) and 1 in non-CR) had a significantly better survival rate than 10 patients transplanted with a conventional conditioning (4 in CR and 6 in non-CR) (3-year EFS (95% confidence interval): 80.0% (20.4-96.9%) vs. 10.0% (0.6%-35.8%), P = 0.039).

Continuous regional arterial infusion effective for children with acute necrotizing pancreatitis even under neutropenia.

Severe acute pancreatitis is one of the critical conditions that may develop in children with cancer. The leading cause of death due to acute pancreatitis is infectious pancreatitis or circulation collapse. Therefore, patients who develop acute pancreatitis while undergoing chemotherapy or after hematopoietic transplantation are at risk for a life-threatening and fatal course. We treated 140 patients with malignancy from April 2002 to March 2009 at our hospital and encountered 3 patients under neutropenia who developed severe acute pancreatitis. Two of them were successfully treated with continuous regional arterial infusion of a protease inhibitor and antibiotic even under agranulocytosis. Another patient was treated with conventional therapy with intravenous antibiotics plus a protease inhibitor and total or partial parenteral nutrition. Even though the two patients treated with continuous regional arterial infusion presented much more severe conditions, their symptoms resolved earlier. In conclusion, acute pancreatitis is one of the severe complications of childhood malignancy. Even under agranulocytosis, continuous regional arterial infusion of a protease inhibitor and antibiotic was well tolerated and effective among our cases and might reduce early death due to pancreatitis.

Myeloid/natural killer (NK) cell precursor acute leukemia as a distinct leukemia type.

Myeloid/natural killer (NK) cell precursor acute leukemia (MNKPL) has been described on the basis of its unique immunophenotype and clinical phenotype. However, there is no consensus on the characteristics for identifying this disease type because of its rarity and lack of defined distinctive molecular characteristics. In this study, multiomics analysis revealed that MNKPL is distinct from acute myeloid leukemia, T cell acute lymphoblastic leukemia, and mixed-phenotype acute leukemia (MPAL), and NOTCH1 and RUNX3 activation and BCL11B down-regulation are hallmarks of MNKPL. Although NK cells have been classically considered to be lymphoid lineage-derived, the results of our single-cell analysis using MNKPL cells suggest that NK cells and myeloid cells share common progenitor cells. Treatment outcomes for MNKPL are unsatisfactory, even when hematopoietic cell transplantation is performed. Multiomics analysis and in vitro drug sensitivity assays revealed increased sensitivity to l-asparaginase and reduced levels of asparagine synthetase (ASNS), supporting the clinically observed effectiveness of l-asparaginase.

Impact of chronic GVHD on QOL assessed by visual analogue scale in pediatric HSCT survivors and differences between raters: a cross-sectional observational study in Japan.

A nationwide cross-sectional survey was conducted in long-term survivors of allogeneic hematopoietic stem cell transplantation (HSCT) in childhood to investigate the effect of chronic graft-versus-host disease (cGVHD) on quality of life (QOL) and differences in QOL assessments between raters. QOL was evaluated by a visual analogue scale (VAS). Assessments were compared between the survivor, guardian, and attending pediatrician for those aged 15 years or younger, and between the survivor and attending pediatrician for those aged 16 years or older. For cGVHD, severity scores were obtained by organ and their association with the VAS score was analyzed. The average pediatrician-rated VAS score was higher than that of other raters for both patient age groups (< 15 years and > 16 years). By organ, involvement of the skin, digestive organs, and joints in GVHD affected the VAS scores. A high joint score was associated with a low VAS score, and conversely, a high lung score was associated with a low pediatrician-rated VAS score. Our results indicate that differences between raters must be considered when evaluating QOL of HSCT survivors, because patients appeared to experience grater inconvenience and difficulties due to joint GVHD than their pediatricians perceived.

Karnofsky performance status and visual analogue scale scores are simple indicators for quality of life in long-term AYA survivors who received allogeneic hematopoietic stem cells transplantation in childhood.

The purpose of this study was to investigate Karnofsky performance status (KPS) scores and visual analogue scale (VAS) scores to explain which domains in the standardized self-reported quality of life (QOL) are instrumental for long-term hematopoietic stem cell transplantation (HSCT) survivors. We conducted a nationwide cross-sectional questionnaire study on 221 survivors with allogeneic-HSCT in 28 pediatric centers. Patient-reported QOL was assessed at a single time point using the 36-item Short-Form Survey (SF-36), the Functional Assessment of Cancer Therapy-Bone Marrow Transplant (FACT-BMT), and VAS scores. KPS scores were significantly correlated with both physical and role component summary scores of the SF-36, while the VAS provided by the patient (VASpt) was significantly correlated with the mental component summary score of the SF-36 and many subscales of the FACT-BMT. The VAS provided by the participants' attending physician (VASdoc) was correlated well with KPS scores. A VASpt score more than 40% lower than KPS scores suggested mental health problems. In conclusion, KPS scores might be considered as an indicator for physical and role/social components and VASpt score as an indicator for mental components and HSCT-specific QOL.

Outcome of unrelated umbilical cord blood transplantation in 88 patients with primary immunodeficiency in Japan.

We report the results of umbilical cord blood transplantation (UCBT) performed in 88 patients with primary immunodeficiency (PID) between 1998 and 2008 in Japan; severe combined immunodeficiency (SCID, n = 40), Wiskott-Aldrich syndrome (WAS, n = 23), chronic granulomatous disease (n = 7), severe congenital neutropaenia (SCN, n = 5) and other immunodeficiencies (n = 13). Five-year overall survival (5-year OS) for all patients was 69% [95% confidence interval (CI), 57-78%], and was 71% and 82% for SCID and WAS, respectively. The main cause of death before day 100 was infection (17/19), while that after day 100 was graft-versus-host disease (GVHD) (5/7). Using multivariate analyses, pre-transplant infection, no conditioning, ≥ 2 human leucocyte antigen (HLA) mismatches or diagnosis other than SCID, SCN or WAS were all associated with poor prognosis. Reduced-intensity conditioning was associated with decreased overall mortality compared with myeloablative therapy. The cumulative incidence of grade 2-4 acute GVHD at day 100 was 28% (95% CI, 19-38%), and that of chronic GVHD at day 180 was 13% (95% CI, 7-23%). We conclude that UCBT should be considered for PID patients without an HLA-matched sibling. The control of pre-transplant infection and selection of HLA-matched donors will lead to a better outcome.

Outcome of 125 children with chronic myelogenous leukemia who received transplants from unrelated donors: the Japan Marrow Donor Program.

Because of a small number of patients, only a few studies have addressed the outcome of bone marrow transplantation (BMT) in children with Philadelphia chromosome-positive (Ph+) chronic myelogenous leukemia (CML), who receive graft from a volunteer-unrelated donor (VUD), especially after practical application of imatinib mesylate. The outcomes of BMT from a VUD in 125 children with Ph+ CML were retrospectively reviewed. Patients were identified through the Japan Marrow Donor Program as having undergone BMT between 1993 and 2005 and were aged 1-19 years at the time of transplant (median age, 14 years). The probabilities of 5-year overall survival (OS) and leukemia-free survival (LFS) were 59.3% and 55.5%, respectively. Multivariate analysis identified the following unfavorable survival factors: infused total nucleated cell dose<314 x 10(6) /kg (relative risk [RR]=2.43; 95% confidence interval [CI]=1.33-4.44; P=.004), advanced phase (RR=2.43; 95% CI=1.37-4.31; P=.004), and no major cytogenetic response (MCyR) at the time of BMT (RR=6.55; 95% CI=1.98-21.6; P=.002). Of the 17 patients treated with imatinib, 15 (88%) achieved MCyR at the time of BMT, and this group had an excellent 5-year OS of 81.9%. Disease phase, infused total nucleated cell dose, and cytogenetic response were independent risk factors for survival of unrelated BMT. These findings provide important information for assessing the indications for and improving outcome in unrelated BMT for the treatment of pediatric CML.