Reduced-intensity allogenic transplantation for children and adolescents with Philadelphia chromosome-positive acute lymphoblastic leukemia.

Survival rates of patients with Philadelphia chromosome-positive ALL (Ph+ALL) have improved considerably with the introduction of tyrosine kinase inhibitors (TKI); however, hematopoietic stem cell transplantation (HSCT) continues to play an important role. Reduced-intensity conditioning (RIC) regimens have been widely applied particularly for older patients, but their validity for children and adolescents with Ph+ALL has not been investigated. In this study, data from patients receiving HSCT for de novo Ph+ALL in first or second remission at ages younger than 25 years and with a history of pre-HSCT TKI therapy were retrospectively collected through the nationwide registry in Japan. In 265 patients who received myeloablative conditioning (MAC) and 33 patients receiving RIC, 5-year leukemia-free survival (LFS) rates were 67.3% and 79.8%, respectively (p = 0.142). Multivariate analysis of LFS, focusing on patients with good performance status, identified RIC as a significant prognostic factor for LFS (hazard ratio 0.32, p = 0.032), as well as older age, higher leukocyte count at diagnosis, and disease with additional chromosomal abnormalities. These trends were similar when we focused on patients who received prophylactic post-HSCT TKI treatment, as 5-year LFS was 81.0% for MAC and 84.4% for RIC (p = 0.748). In summary, HSCT with RIC regimen showed at least comparable LFS to HSCT with MAC regimen, and RIC was an independent favorable prognostic factor on multivariate analysis adjusting potential prognostic factors. While patient numbers were limited, our data suggest that RIC may be safely applied in this group, particularly combined with prophylactic post-HSCT TKI maintenance therapy.

JACLS ALL-02 SR protocol reduced-intensity chemotherapy produces excellent outcomes in patients with low-risk childhood acute lymphoblastic leukemia.

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer. As overall cure rates of childhood ALL have improved, reduction of overall treatment intensity while still ensuring excellent outcomes is imperative for low-risk patients. We report the outcomes of patients treated following the standard-risk protocol from the prospective Japan Association of Childhood Leukemia Study (JACLS) ALL-02 study, which was conducted between 2002 and 2008 for patients with newly diagnosed ALL aged 1-18 years. Of 1138 patients with B-cell precursor ALL, 388 (34.1%) were allocated to this protocol. Excellent outcomes were achieved despite the overall treatment intensity being lower than that of most contemporary protocols: 4 years event-free survival (EFS) was 92.3% and 4 years overall survival 98.2%. Patients with high hyperdiploidy (HHD) involving triple trisomy (trisomy of chromosomes 4, 10, and 17) or ETV6-RUNX1 had even better outcomes (4 years EFS 97.6% and 100%, respectively). Unique characteristics of this protocol include a selection of low-risk patients with a low initial WBC count and good early treatment response and reduction of cumulative doses of chemotherapeutic agents while maintaining dose density. In Japan, we are currently investigating the feasibility of this protocol while incorporating minimal residual disease into the patient stratification strategy.

Low-Level Germline 48,XYY,+21 Mosaicism Associated with Transient Abnormal Myelopoiesis in a Phenotypically Normal Neonate.

Transient abnormal myelopoiesis (TAM) is a unique neonatal leukemoid reaction caused by a pathognomonic GATA1 mutation in conjunction with the gene dosage effect of trisomy 21, which is either of germline or somatic origin. We encountered a 48,XYY,+21 phenotypically normal neonate with Down syndrome who developed TAM due to cryptic germline mosaicism. Quantification of the mosaic ratio was complicated by an overestimation bias of hyperproliferating TAM within the germline component. To establish a workflow for such a clinical scenario, we analyzed the cytogenetic findings of neonates with TAM associated with somatic or low-level germline mosaicism. We showed that multistep diagnostic procedures (i.e., paired cytogenetic analyses of peripheral blood specimens in culture with or without phytohemagglutinin; serial cytogenetic studies of more than one tissue, such as the buccal membrane; and complementary DNA-based GATA1 mutation screening) can verify the specificity of cytogenetic testing for phenotypically normal neonates with TAM suspected of mosaicism.

Sensitive detection of GATA1 mutations using complementary DNA-based analysis for transient abnormal myelopoiesis associated with the Down syndrome.

INTRODUCTION: GATA1 mutation plays an important role in initiating transient abnormal myelopoiesis (TAM) and in the clonal evolution towards acute megakaryoblastic leukaemia (AMKL) associated with Down syndrome (DS). This study aimed to develop and validate the clinical utility of a complementary DNA (cDNA) analysis in parallel with the conventional genomic DNA (gDNA) Sanger sequencing (Ss), as an initial screening test for GATA1 mutations. METHODS: GATA1 mutations were evaluated using both gDNA and cDNA in 14 DS patients using Ss and fragment analysis (FA), respectively. RESULTS: The detection sensitivity of conventional gDNA sequencing was limited in low blast percentage TAM (LBP-TAM); however, cDNA-based Ss readily detected all the pathognomonic GATA1 mutations. The cDNA-based FA readily detected GATA1 frameshift mutation with a reliable sensitivity ranging from 0.005% to 0.01% of clonal cells. CONCLUSIONS: GATA1 mutations are heterogeneous; therefore, we would like to propose a dual cDNA and gDNA analysis as a standard diagnostic approach, especially for LBP-TAM. cDNA-based FA promises an excellent sensitivity for detecting frameshift GATA1 mutations in the longitudinal clonal evolution towards AMKL without using a patient specific primer.

The incidence of symptomatic osteonecrosis is similar between Japanese children and children in Western countries with acute lymphoblastic leukaemia treated with a Berlin-Frankfurt-Münster (BFM)95-based protocol.

In this study, we performed a retrospective analysis of a cohort of Japanese paediatric patients with B-cell precursor (BCP)-acute lymphoblastic leukaemia (ALL) treated with a Berlin-Frankfurt-Münster (BFM)95-based protocol, to clarify the incidence, clinical characteristics, and risk factors of osteonecrosis (ON) in comparison to the ALL-02 protocol. We identified a high frequency of ON with the BFM95-based protocol compared to the ALL-02 protocol. The incidence of symptomatic ON with the BFM95-based protocol is comparable to previous studies in Western countries. We believe that the type of treatment regimen has more impact on the incidence of symptomatic ON in paediatric ALL than ethnicity.

Cell-free DNA Oncogene Copy Number as a Surrogate Molecular Biomarker in ALK/MYCN-coamplified Neuroblastoma.

Secondary expansion and/or evolution of aggressive subclones are associated with the disease progression and resistance to chemotherapy in neuroblastoma, and it is important to track the clonal changes during the treatment period. Cell-free (cf) DNA analysis, namely liquid biopsy, can detect the genomic change of tumor cells without surgical procedures. In this report, we showed that serial polymerase chain reaction-based cf DNA neuroblastoma proto-oncogene quantification is sensitive enough to evaluate the aggressive cellular characteristics of ALK/MYCN-coamplified neuroblastoma and stressed the promise of cf DNA analyses as a reliable molecular marker in advanced neuroblastoma.

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.

Cerebral Sinovenous Thrombosis and Subdural Hematoma as Treatment-Related Complications in Suprasellar Germ Cell Tumor Associated with Adipsic Diabetes Insipidus.

Cerebral sinovenous thrombosis (CSVT) is a rare but not a negligible complication in pediatric brain tumor. An 11-year-old male with suprasellar germ cell tumor developed treatment-related vascular complications of CSVT and subdural hematoma. The underlying mechanism of CSVT was attributed to multiple risk factors, such as adipsic diabetes insipidus, obesity, central apnea, and chemotherapy-induced endothelial injury. In an attempt to minimize the possible risk of vascular complications, including late effect in pediatric brain tumors, we would like to stress the importance of individualized supportive therapy, i.e., hormone replacement, fluid management, thromboprophylaxis, and bi-level positive airway pressure therapy.

Successful treatment with 2-chlorodeoxyadenosine of refractory pediatric Langerhans cell histiocytosis with initial involvement of the gastrointestinal tract.

Gastrointestinal (GI) tract involvement in Langerhans cell histiocytosis (LCH) is extremely rare. Langerhans cell histiocytosis with GI tract involvement (GI-LCH) is frequently associated with multi-system disease, and usually presents with severe systemic symptoms, such as protein-losing enteropathy (PLE). Although the GI tract is not included among the organs at risk, the prognosis of GI-LCH is poor, and no effective chemotherapeutic regimen has been identified. Here, we report an infant case of primary refractory GI-LCH with PLE that showed marked improvement in response to 2-chlorodeoxyadenosine (2-CdA) therapy with no severe adverse events, even under conditions of deteriorating general health. The present findings indicate that 2-CdA may be effective for refractory GI-LCH with PLE. Further studies are warranted to determine the optimal therapeutic strategies for GI-LCH with PLE.

Discontinuation of L-asparaginase and poor response to prednisolone are associated with poor outcome of ETV6-RUNX1-positive pediatric B-cell precursor acute lymphoblastic leukemia.

ETV6-RUNX1-positive B precursor acute lymphoblastic leukemia (B-ALL) is a common subtype of pediatric B-ALL that has shown excellent outcomes in contemporary clinical trials for pediatric B-ALL. Examinations of the possibility of reducing therapeutic intensity may thus be explored. This prospective study examined outcomes in 205 pediatric patients with ETV6-RUNX1-positive B-ALL uniformly treated following the Japan Association of Childhood Leukemia Study Group (JACLS) ALL-02 protocol. The JACLS ALL-02 protocol does not employ minimal residual disease detected by polymerase chain reaction (PCR-MRD)-based risk stratification; however, 4-year event-free survival (EFS) and overall survival (OS) were 94.4 ± 1.6 and 97.5 ± 1.1%, respectively. In particular, 92 of 205 (44.9%) patients were successfully treated with a less intensive regimen involving only two cycles of high dose methotrexate and one course of re-induction therapy comprising vincristine, L-asparaginase (L-asp), pirarubicin, and prednisolone. Multivariate analysis revealed that discontinuation of L-asp and poor response to prednisolone was, respectively, associated with poor EFS (HR 6.3; 95% CI 1.3-27.0) and OS (HR 17.5; 95% CI 2.3-130), suggesting that the majority of ETV6-RUNX1-positive B-ALL cases may be cured by a less-intensive chemotherapy regimen if the risk stratification system including PCR-MRD monitoring and insufficient use of L-asp is avoided.

Role of monocyte chemoattractant protein-1 in liver fibrosis with transient myeloproliferative disorder in down syndrome.

Liver fibrosis is a common complication associated with transient myeloproliferative disorder (TMD) in Down syndrome (DS). The exact molecular pathogenesis that regulates disease progression is largely unknown. We recently found serum and/or urinary monocyte chemoattractant protein-1 (MCP-1) as a novel biomarker of liver fibrosis. This study was an in vitro analysis to investigate the fibrogenic activity of MCP-1 using the collagen-producing LX-2 human hepatic stellate cell line. We also examined the fibrogenic activity of serum from a male neonate with DS in whom late-onset liver fibrosis developed even after the resolution of TMD. MCP-1 stimulated both cell growth and collagen synthesis of LX-2 in a dose-dependent manner. Patient serum obtained during the active disease phase significantly up-regulated fibrogenic activity, which was suppressed in the presence of MCP-1-blocking antibody. Transient transforming growth factor beta 1 stimulation primed LX-2 to induce prolonged hypersecretion of MCP-1 in the culture supernatant and in collagen synthesis, which was suppressed with MCP-1 blocking antibody as well. Conclusion: MCP-1 accounts for the prolonged activation of collagen-producing hepatic stellate cells in both a paracrine and autocrine manner, thereby promoting liver fibrosis. Anti-cytokine therapy targeting the fibrogenic cytokines of MCP-1, for example, herbal medicine, could provide a new therapeutic intervention for liver fibrosis associated with TMD in DS. (Hepatology Communications 2018;2:230-236).

Monocyte Chemoattractant Protein-1 (MCP-1) as a Potential Therapeutic Target and a Noninvasive Biomarker of Liver Fibrosis Associated With Transient Myeloproliferative Disorder in Down Syndrome.

Liver fibrosis is one of the common complications of transient myeloproliferative disorder (TMD) in Down syndrome (DS), but the exact molecular pathogenesis is largely unknown. We herein report a neonate of DS with liver fibrosis associated with TMD, in which we performed the serial profibrogenic cytokines analyses. We found the active monocyte chemoattractant protein-1 expression in the affected liver tissue and also found that both serum and urinary monocyte chemoattractant protein-1 concentrations are noninvasive biomarkers of liver fibrosis. We also showed a prospective of the future anticytokine therapy with herbal medicine for the liver fibrosis associated with TMD in DS.

Long-term Results of the Risk-adapted Treatment for Childhood B-Cell Acute Lymphoblastic Leukemia: Report From the Japan Association of Childhood Leukemia Study ALL-97 Trial.

PURPOSE: This study was conducted as the first clinical trial by Japan Association of Childhood Leukemia Study to improve the outcome of B-cell acute lymphoblastic leukemia and explore a less toxic reinduction block. PATIENTS AND METHODS: From 1997 to 2002, 563 patients with B-cell acute lymphoblastic leukemia aged 1 to 15 years were enrolled. The patients were assigned into 4 risk groups (standard, intermediate, high, or extremely high risk) and treated with regimens intensified according to the risk. Two randomized trials were conducted to compare 2 regimens with and without a 3-week reinduction therapy in the standard-risk group, and to compare the efficacy of pirarubicin with daunorubicin in the intermediate-risk and high-risk groups. Prophylactic cranial irradiation was restricted in patients with high or extremely high risk. RESULTS: The event-free survival (EFS) rate at 10 years for all patients was 77.0%. Those in the standard-risk to extremely high-risk groups were 79.3%, 72.5%, 71.7%, and 66.3%, respectively. The 15-week induction/consolidation not followed by reinduction produced 76.4% of the EFS at 10 years comparable with the regimen with reinduction therapy. Pirarubicin at 25 mg/m administered 11 times throughout the treatment produced the EFS comparable with daunorubicin at 30 mg/m. CONCLUSION: The trial produced high survival rates in NCI-HR patients, although the outcomes in NCI-SR patients were not satisfactory possibly due to less intensive central nervous system-directed therapy.

Acute and late toxicities of pirarubicin in the treatment of childhood acute lymphoblastic leukemia: results from a clinical trial by the Japan Association of Childhood Leukemia Study.

BACKGROUND: Anthracyclines are used to treat childhood acute lymphoblastic leukemia (ALL). Even when administered at low doses, these agents are reported to cause progressive cardiac dysfunction. We conducted a clinical trial comparing the toxicities of two anthracyclines, pirarubicin (THP) and daunorubicin (DNR), in the treatment of childhood ALL. The results from our study that relate to acute and late toxicities are reported here. METHODS: 276 children with B-ALL were enrolled in the trial from April 1997 to March 2002 and were randomly assigned to receive a regimen including either THP (25 mg/m2 × 11) or DNR (30 mg/m2 × 11). Acute toxicity was prospectively assessed based on the National Cancer Institute Common Toxicity Criteria. Acute hematological toxicity was also examined via some parameters. Patients with event-free survival of >5 years were retrospectively surveyed for cardiac function at 5 and 10 years and at the most recent assessment more than 10 years from the onset of ALL. RESULTS: Acute hematological toxicity in the early phase was more significant in the THP arm. Based on ultrasound cardiography, cardiac function was impaired in both groups during the follow-up period, but there was no significant difference between the groups except for a greater decline in fractional shortening on ultrasound cardiography in the DNR arm. CONCLUSIONS: While acute hematological toxicity was more significant in the THP arm, THP also appeared to be less cardiotoxic. However, the evaluation of late cardiotoxicity was limited because only a few subjects were followed beyond 10 years after ALL onset. Considering that the THP regimen produced an EFS rate comparable with that of the DNR regimen, the efficacy and toxicity of THP at reduced doses should be studied in order to identify potentially safer regimens.

Development of CMV retinitis in an antigenemia-negative infant after cord blood transplantation.

A five-month-old male infant with familial hemophagocytic lymphohistiocytosis underwent cord blood transplantation using reduced-intensity conditioning. Methylprednisolone (mPSL) pulse administration was performed for marked pulmonary edema during the early phase of transplantation, followed by GVHD treatment with mPSL until day 100. CMV antigenemia was detected on days 27 and 55, but serum became negative with 2- to 3-week ganciclovir (GCV) treatment on both occasions. On day 120, ophthalmological findings included multiple bilateral white spots and a positive PCR study using anterior chamber fluid confirmed the diagnosis of CMV retinitis affecting both eyes, although CMV antigenemia was negative. Re-treatment with GCV had a minimal effect on the ophthalmological findings, while foscarnet administration markedly improved the retinitis and decreased the CMV-DNA level. Considering that a substantial proportion of patients develop CMV retinitis even when CMV antigenemia is not present, routine monitoring involving ophthalmological examinations should be conducted for hematopoietic transplant patients, especially infants, who cannot complain of ocular symptoms.