Clinical impact of minimal residual disease and genetic subtypes on the prognosis of childhood acute lymphoblastic leukemia.

BACKGROUND: This study analyzed data from two consecutive protocols for children newly diagnosed with acute lymphoblastic leukemia (ALL) to determine the clinical impact of minimal/measurable residual disease (MRD) and recently identified tumor genetic subtypes. METHODS: Genetic subtypes were determined by sequential approaches including DNA indexing, reverse transcriptase-polymerase chain reaction, multiplex ligation-dependent probe amplification, and RNA-sequencing. MRD was assessed by flow cytometry. The Taiwan Pediatric Oncology Group TPOG-ALL-2013 study enrolled patients who received MRD-directed therapy. RESULTS: The 5-year event-free survival (EFS) and overall survival rates in the 2013 cohort were 77.8% and 86.9% compared to those of the 2002 cohort, which were 62.4% and 76.5%. Among patients treated with MRD-guided therapy, those with ETV6-RUNX1 fusion and high hyperdiploidy had the highest 5-year EFS (91.4% and 89.6%, respectively). The addition of dasatinib improved outcomes in patients with BCR-ABL1 ALL. Recently identified subtypes like DUX4-rearranged, ZNF384-rearranged, MEF2D-rearranged, and PAX5alt subtypes were frequently positive for MRD after remission induction, and these patients consequently received intensified chemotherapy. Treatment intensification according to the MRD improved the outcomes of patients presenting DUX4 rearrangements. In high-risk or very-high-risk subtypes, the TPOG-ALL-2013 regimen did not confer significant improvements compared to TPOG-ALL-2002, and the outcomes of BCR-ABL1-like, MEF2D-rearranged, and KMT2A-rearranged ALL subtypes (in addition to those of T-cell ALL) were not sufficiently good. Novel agents or approaches are needed to improve the outcomes for these patients. CONCLUSIONS: The TPOG-ALL-2013 study yielded outcomes superior to those of patients treated in the preceding TPOG-ALL-2002 study. This study provides important data to inform the design of future clinical trials in Taiwan. PLAIN LANGUAGE SUMMARY: MRD-directed therapy improved the outcomes for pediatric ALL, especially standard-risk patients. Genomic analyses and MRD might be used together for risk-directed therapy of childhood ALL. Our work provides important data to inform the design of future clinical trials in Taiwan.

Children with chronic myeloid leukaemia treated with front-line imatinib have a slower molecular response and comparable survival compared with adults: a multicenter experience in Taiwan.

BACKGROUND: The direct comparison of molecular responses of front-line imatinib (IM) monitored at the same laboratory between children and adults with chronic phase (CP) of chronic myeloid leukaemia (CML) had not been reported. In this multicenter study, we compared the landmark molecular responses and outcomes of paediatric and adult CML-CP cohorts treated with front-line IM in whom the BCR::ABL1 transcript levels were monitored at the same accredited laboratory in Taiwan. METHODS: Between June 2004 and July 2020, 55 newly diagnosed paediatric and 782 adult CML-CP patients, with molecular diagnosis and monitoring at the same reference laboratory in Taiwan, were enrolled. The criteria of 2020 European LeukemiaNet were applied to evaluate the molecular responses. RESULTS: By year 5, the cumulative incidences of IS <1%, MMR, MR4.0 and MR4.5 of paediatric patients were all significantly lower than those of adult patients (58 vs 75%, 48 vs 66%, 25 vs 44%, 16 vs 34%, respectively). The 10-year progression-free survival (PFS) (90%) and overall survival (OS) (94%) of paediatric patients did not differ from those (92%) of adult patients. CONCLUSIONS: We demonstrated the paediatric cohort had slower molecular responses to front-line IM and similar outcomes in 10-year PFS and OS in real-world practice.

Surgical treatment confers prognostic significance in pediatric malignant mediastinal germ cell tumors.

BACKGROUND: Primary malignant mediastinal germ cell tumors (GCTs) are rare pediatric tumors that have a poorer prognosis compared to GCTs occurring elsewhere in the body. The current study aimed to assess the prognostic factors and treatment outcomes of children with primary malignant mediastinal GCT in Taiwan. METHODS: The authors retrospectively reviewed children 0-18 years old who were newly diagnosed with primary malignant mediastinal GCT between January 1, 2005 and December 31, 2019 and were registered in the Taiwan Pediatric Oncology Group patient registry. The impact of presenting characteristics, including sex, age, tumor stage, histology subtype, surgical treatment, and chemotherapy regimens of the patients were analyzed. RESULTS: This study enrolled 52 children with malignant mediastinal GCT who had a median age of 16.0 (range, 6.0-17.9) years at diagnosis. The most common histological subtypes were mixed GCTs (n = 20) and yolk sac tumors (n = 15). Advanced disease stage and choriocarcinoma histology subtype were associated inferior outcomes. Children who received surgical treatment exhibited better outcomes compared to those who did not (5-year overall survival, 78% vs. 7%, p < .001). After comparing patients who received first-line cisplatin- and carboplatin-based chemotherapy, no difference in treatment outcomes was observed. Multivariate analysis showed that surgical management was the only independent predictor for superior OS. CONCLUSIONS: Surgical treatment is recommended for mediastinal GCT. Cisplatin-based chemotherapy was not superior to carboplatin-based chemotherapy as first-line treatment and may be avoided due to toxicity concerns.

Lymphoma-based therapy for refractory or relapsed Epstein-Barr virus-related hemophagocytic lymphohistiocytosis in children.

Epstein-Barr virus-related hemophagocytic lymphohistiocytosis (EBV-HLH) is a life-threatening hyperinflammatory syndrome. Although etoposide-based immunochemotherapy has improved survival rates, consensus regarding the appropriate salvage therapy for patients with refractory or relapsed EBV-HLH is lacking. We performed a retrospective study to examine the efficacy of a lymphoma-based treatment regimen for children with refractory or relapsed EBV-HLH. The data of six children were analyzed. Four had cytogenetic abnormalities, and two experienced a transition to EBV-positive T-cell lymphoma. They were treated with an intensive chemotherapy regimen modified from that used in the Berlin-Frankfurt-Münster Group Trial as salvage therapy. Five patients (83%) achieved complete response. Four patients (67%) were disease free for a median of 10 years without undergoing allogeneic hematopoietic stem cell transplantation. No grade 3 or 4 nonhematologic adverse events occurred. Lymphoma-based chemotherapy is a potential curative treatment for some subgroups of children with refractory or relapsed EBV-HLH.

Outcome of young adult patients with very-high-risk acute lymphoblastic leukemia treated with pediatric-type chemotherapy - a single institute experience.

BACKGROUND/PURPOSE: Adult patients of acute lymphoblastic leukemia (ALL) with very high-risk (VHR) characteristics have an inferior outcome, and allogeneic hematopoietic stem cell transplantation (HSCT) is usually performed. In contrast, VHR pediatric patients can be treated effectively with minimal residual disease (MRD)-guided pediatric protocols and HSCT are not always needed. METHODS: We retrospectively reviewed young adult ALL VHR patients treated with the pediatric-type (TPOG-ALL-2002 VHR) regimen in our institute from 2008 to 2019 and compared the event-free survival (EFS) with patients treated with an adult-type regimen (Hyper-CVAD alternating with high dose methotrexate and cytarabine). RESULTS: We identified 16 patients treated with the TPOG and 11 treated with the Hyper-CVAD regimen. Philadelphia chromosome-positive (n = 10) and T-cell immunophenotype (n = 11) are the most common VHR features. Compared with the Hyper-CVAD group, patients treated with the TPOG regimen showed a trend toward better EFS with a hazard ratio (HR) of 0.42 (p = 0.16). Compared with untransplanted patients, HSCT showed a positive trend in the Hyper-CVAD (HR 0.22, p = 0.12) but not in the TPOG group (p = 0.37). Untransplanted patients treated initially with the hyper-CVAD regimen had a significantly worse outcome than the TPOG regimen (HR 4.19, p < 0.05). In the TPOG group, patients with negative MRD at the end of consolidation had a significantly better outcome (HR 0.12, p = 0.03). CONCLUSION: Young adult VHR patients can be effectively treated with the TPOG-ALL-2002 protocol, and those who achieved MRD negativity before the end of consolidation have a good outcome without allogeneic HSCT.

Characteristics and outcomes of second cancers in patients with childhood cancer: A report from the Taiwan Pediatric Oncology Group.

BACKGROUND: Patients with childhood cancer are at increased risk for the development of second cancers. METHODS: A national multicenter survey of second cancers conducted by the Taiwan Pediatric Oncology Group retrieved retrospective data from the database at the Children Cancer Foundation in Taiwan beginning in 1995. The characteristics of second cancers and associations of patient demographic and clinical characteristics with time to death due to a second cancer were analyzed. RESULTS: We examined the records of 8782 patients with a primary cancer diagnosed between January 1, 1995 and December 31, 2013, and a total of 99 patients with a second cancer were identified. The most common type of second cancer was acute myeloid leukemia (n = 35), followed by acute lymphoblastic leukemia (n = 15), central nervous system (CNS) tumors (n = 15), and sarcomas (n = 10). Secondary hematological malignancies occurred earlier than other secondary cancers. The frequencies of second CNS tumors and second bone cancers and sarcomas were notably increased when prior radiation doses increased from zero, low dose to high dose. The overall 5-year survival of patients with a second cancer was poor (33.7%). Multivariate survival analysis revealed that the year of primary diagnosis ≤2002, secondary hematological malignancies, and age at second cancer diagnosis ≤9.3 years or >26.8 years increased the risk of death following second cancer. CONCLUSION: Children who develop a second cancer have an unfavorable outcome. Early detection and improved treatment for second cancers are needed.

Rhabdomyosarcoma in a child with nephrotic syndrome treated with cyclosporine: a case report with literature review.

BACKGROUND: In patients with frequently relapsing nephrotic syndrome, immunosuppressive therapy such as cyclosporine are often required to maintain remission. Cyclosporine has been noted to have tumorgenesis effects. In this case report, we present a child with relapsing nephrotic syndrom developed a rhabdomyosarcoma on her tongue after adout 4 years of continual immunosuppressive therapy. CASE PRESENTATION: A 2-year-old female child had nephrotic syndrome (urine protein-creatinine ratio 749.1 mg/mg; blood urea nitrogen 11 mg/dL; serum creatinine 0.3 mg/dL; and serum albumin 1.8 g/dL.) Proteinuria resolved on treatment with daily prednisolone for 4 weeks at the dose of 45 mg (2.5 mg/kg/day) but recurred with taper from 25 mg/day to 10 mg/day. At least five more episodes of relapse occurred within about a 3-year period. After the third relapse, she was treated with prednisolone and cyclosporine (at initial dose of 50 mg/day [1.7 mg/kg/day]) for immunosuppression. About 4 years after the diagnosis of nephrotic syndrome had been made, an embryonal rhabdomyosarcoma developed on her tongue. The cancer was treated with TPOG-RMS-LR protocol, with vincristine, actinomycin, and cyclophosphamide. Magnetic resonance imaging scan, performed about 3 years after the start of TPOG-RMS-LR therapy, revealed complete remission of the cancer. CONCLUSIONS: Although treatment with cyclosporine cannot be conclusively implicated as the cause the rhabdomyosarcoma in this patient, the association should prompt consideration of its use in the treatment of frequently relapsing nephrotic syndrome in children.

Incidence and treatment outcome of aplastic anemia in Taiwan-real-world data from single-institute experience and a nationwide population-based database.

Aplastic anemia (AA) is a rare disease characterized by pancytopenia and bone marrow failure. The incidence of AA tends to be higher in Asia than in the West, but real-world data about AA in Asia remain limited. We aimed to describe the basic data, treatment, and outcome of AA patients from our institute and evaluate the incidence of AA in Taiwan with a nationwide population-based cohort from National Health Insurance Research Database (NHIRD). We identified patients older than 2 years with AA in the Registry of Catastrophic Illness of NHIRD between 2001 and 2010 and excluded patients with any diagnosis suggestive of congenital or secondary bone marrow failure. With a total of 1270 patients, the overall incidence was 5.67 per million people per year, and there was a biphasic age distribution of incidence rate, highest in ≥ 70 years (19.83 per million people per year) and another peak at age 2-9 years (5.26 per million people per year). Overall, the 5-year survival was 60.0%. Hematopoietic stem cell transplantation (HSCT) and anti-thymocyte globulin-based immunosuppressive therapy (IST) were the major first-line treatments in patients younger than 40 years and were linked with good survival. In contrast, the majority of patients older than 60 years were treated with androgen, and the survival was poor. In multivariate analysis, "severe AA," "very severe AA," and "treatment other than HSCT, IST, or androgen" were independent risk factors for inferior survival. In conclusion, the incidence of AA in Taiwan is consistent with nearby Asian countries and is higher than in the West. Advanced age is associated with higher incidence and poorer outcome.

Treatment of childhood acute lymphoblastic leukemia with delayed first intrathecal therapy and omission of prophylactic cranial irradiation: Results of the TPOG-ALL-2002 study.

BACKGROUND: To eliminate cranial irradiation (CrRT)-related sequelae and to minimize the adverse impact of traumatic lumbar puncture (TLP) with blasts, the Taiwan Pediatric Oncology Group (TPOG) introduced a modified central nervous system (CNS)-directed regimen characterized by delayed triple intrathecal therapy (TIT) and the omission of CrRT for all children with newly diagnosed acute lymphoblastic leukemia (ALL). METHODS: This study compared the treatment outcomes of patients overall and patients with a non-CNS-1 status (CNS-2, CNS-3, or TLP with blasts) in 2 treatment eras, one before and another after the revision of the TPOG-ALL-2002 protocol by the introduction of the modification (era 1 [2002-2008] with CrRT and era 2 [2009-2012] with delayed first TIT and no CrRT). RESULTS: There were no statistically significant differences in major outcomes between the 903 patients treated in era 1 and the 444 patients treated in era 2: the 5-year event-free survival (EFS) rates were 75.7% ± 1.4% and 72.1% ± 2.4%, respectively (P = .260), and the cumulative risks of isolated CNS relapse were 4.0% ± 0.7% and 4.1% ± 1.0%, respectively (P = .960). There were also no differences between non-CNS-1 patients treated in era 1 (n = 76) and era 2 (n =28): the 5-year EFS rates were 52.3% ± 5.8% and 62.9% ± 9.4%, respectively (P = .199), and the cumulative risks of isolated CNS relapse were 6.3% ± 3.1% and 3.6% ± 3.5%, respectively (P = .639). Notably, TLP with blasts was completely eliminated after the first TIT was delayed in era 2. CONCLUSIONS: The delay of the first TIT until the clearance of circulating blasts and the total omission of CrRT did not compromise survival or CNS control in patients with childhood ALL, including those with a non-CNS-1 status.

Pediatric acute lymphoblastic leukemia with t(1;19)/TCF3-PBX1 in Taiwan.

BACKGROUND: In childhood acute lymphoblastic leukemia (ALL), t(1;19)(q23;p13.3) with TCF3-PBX1 fusion is one of the most frequent translocations. Historically, it has been associated with poor prognosis. Intensive treatment, however, has improved its outcome. We determined the outcome of children with this genotype treated with contemporary intensive chemotherapy in Taiwan. PROCEDURE: In Taiwan Pediatric Oncology Group 2002 ALL studies, genotypes were determined by cytogenetic analysis and/or reverse transcriptase polymerase chain reaction assay. Based on presenting features, immunophenotype and genotype, patients were assigned to one of the three risk groups: standard risk (SR), high risk (HR), or very high risk (VHR). The patients with t(1;19)/TCF3-PBX1 were treated in the HR arm receiving more intensive chemotherapy. The outcomes of patients with t(1;19)/TCF3-PBX1 were compared to that of patients with other subtypes of B-precursor ALL (B-ALL). RESULTS: Of the 1,129 patients with B-ALL, 64 (5.7%) had t(1;19)/TCF3-PBX1; 51 of whom were treated in the HR arm, but 11 were treated in the VHR and 2 in the SR arm because of physician's preference. As a group, 64 patients with t(1;19)/TCF3-PBX1 had similar 5-year event-free survival (83.3 ± 4.8%) as those with TEL-AML1 (85.2 ± 3.4%, P = 0.984) or those with hyperdiploidy >50 (84.0 ± 3.1%, P = 0.748). The cumulative risk of any (isolated plus combined) central nervous system relapse among patients with t(1;19)/TCF3-PBX1 (8.7 ± 3.8%) tended to be higher than that of patients with TEL-AML1 (5.8 ± 2.3%, P = 0.749) or those with hyperdiploidy (4.1 ± 1.8%, P = 0.135), albeit the differences did not reach statistical significance. CONCLUSIONS: With contemporary intensive chemotherapy, children with t(1;19)/TCF3-PBX1 fared as well as those with favorable genotypes (TEL-AML1 or hyperdiploidy).

Treatment for childhood acute lymphoblastic leukemia in Taiwan: Taiwan Pediatric Oncology Group ALL-2002 study emphasizing optimal reinduction therapy and central nervous system preventive therapy without cranial radiation.

BACKGROUND: Reinduction therapy has improved the outcomes in children with acute lymphoblastic leukemia (ALL). We sought to determine the optimal course(s) of reinduction therapy for standard-risk (SR, or "low-risk" in other groups) patients. Also, we evaluated outcomes using triple intrathecal therapy without cranial radiation (CrRT) for central nervous system (CNS) preventive therapy. PROCEDURE: From 2002 to 2012, all newly diagnosed children with ALL in Taiwan were enrolled in Taiwan Pediatric Oncology Group ALL-2002 protocol. SR patients were randomized to receive single or double reinduction courses. The patients enrolled before 2009 received CrRT, while those enrolled later did not. The Kaplan-Meier method was used to estimate survival rates and the difference between two groups was compared by the two-sided log-rank test. RESULTS: In 1,366 eligible patients, the 5-year overall survival (OS) was 81.6 ± 1.1% (standard error) and 5-year event-free survival (EFS) was 74.3 ± 1.2%. In SR patients, the 5-year OS for one and two reinduction courses was 91.6 ± 2.1% and 93.7 ± 1.8%, respectively, and the 5-year EFS was 85.2 ± 2.7% and 89.8 ± 2.3%, respectively. There were no significant differences in survival between these two groups. Patients with MLL or BCR-ABL1 had the worst outcomes: 5-year EFS was 23.4 and 31.8% and 5-year OS was 28.6 and 44.7%, respectively. There was no significant difference in CNS relapse or survival between the era with or without CrRT. CONCLUSIONS: For SR patients, one-course reinduction was adequate. Triple intrathecal therapy alone successfully prevented CNS relapse.

Cost-effectiveness analysis of carrier and prenatal genetic testing for X-linked hemophilia.

BACKGROUND/PURPOSE: Hemophilia involves a lifelong burden from the perspective of the patient and the entire healthcare system. Advances in genetic testing provide valuable information to hemophilia-affected families for family planning. The aim of this study was to analyze the cost-effectiveness of carrier and prenatal genetic testing in the health-economic framework in Taiwan. METHODS: A questionnaire was developed to assess the attitudes towards genetic testing for hemophilia. We modeled clinical outcomes of the proposed testing scheme by using the decision tree method. Incremental cost-effectiveness analysis was conducted, based on data from the National Health Insurance (NHI) database and a questionnaire survey. RESULTS: From the NHI database, 1111 hemophilic patients were identified and required an average medical expenditure of approximately New Taiwan (NT) $2.1 million per patient-year in 2009. By using the decision tree model, we estimated that 26 potential carriers need to be tested to prevent one case of hemophilia. At a screening rate of 79%, carrier and prenatal genetic testing would cost NT $85.9 million, which would be offset by an incremental saving of NT $203 million per year by preventing 96 cases of hemophilia. Assuming that the life expectancy for hemophilic patients is 70 years, genetic testing could further save NT $14.2 billion. Higher screening rates would increase the savings for healthcare resources. CONCLUSION: Carrier and prenatal genetic testing for hemophilia is a cost-effective investment in healthcare allocation. A case management system should be integrated in the current practice to facilitate patient care (e.g., collecting family pedigrees and providing genetic counseling).

Predictors of Remission in Severe Childhood Immune Thrombocytopenia.

Childhood immune thrombocytopenia (ITP; platelet count < 100 × 109/L) is the most common bleeding disorder in children. A total of 3-5% of children with ITP face a greater risk of bleeding, resulting in significant morbidity and mortality. Childhood ITP is often benign and self-limited; however, children with severe ITP (platelet count < 30 × 109/L) require investigation and monitoring. In addition, 20% of ITP patients may not go into remission (platelet counts < 100 × 109/L by 12 months after diagnosis) and may develop chronic ITP. The early identifying predictors associated with the resolution of severe ITP at the time of diagnosis may be helpful for family guidance. However, there is still controversy about the associations between the clinical factors at the time of initial diagnosis and the definitions of disease remission assessed at different timepoints after diagnosis. This retrospective study aimed to analyze the shared clinical factors among the disease remission definitions at three arbitrarily set timepoints-3, 6, and 12 months after diagnosis. This study retrieved records for hospitalized children aged under 18 years and diagnosed with ITP from the hospital registry in a tertiary university hospital. Clinical variables were recorded by reviewing the medical records with structured data entry for ITP admission. The serial follow-up platelet counts within 12 months after diagnosis were recorded. The times of ITP remission were identified by experienced pediatric hematologists. Patients with mild-form ITP (platelet counts ≥ 30 × 109/L) at diagnosis or who were lost to follow-up within 3 months were excluded. From 1988 to 2019, 546 children were enrolled, and a total of 497 children with severe ITP were included in the further analysis. In total, one (0.2%) died of an intracranial hemorrhage, 363 (73.2%) children went into remission at 3 months, 40 (8.1%) went into remission between 6 and 12 months, and 104 (20.9%) developed chronic ITP. The shared significant predictors for remission by the third, sixth, and twelfth months included pre-adolescent age (<10 years) at diagnosis, abrupt onset (duration of symptoms prior to admission ≤ 2 weeks), and speedy recovery (platelet count > 100 × 109/L at 1 month post diagnosis). ITP patients with positive viral serology tests or vaccination within 4 weeks had trends of delayed remission. In conclusion, diagnosis before preadolescent age, abrupt onset, and speedy recovery may share favorable factors for the remission of childhood ITP assessed at different timepoints.

Real-world bleeding outcomes and product utilization in people with severe-type hemophilia A before and after switching to extended half-life rFVIIIFc prophylaxis therapy.

BACKGROUND: Recombinant factor VIII-Fc (rFVIIIFc) became available in Taiwan in 2018. Before this date, no people with hemophilia A (PwHA) were enrolled in a clinical trial of rFVIIIFc. We investigated changes in bleeding outcomes and product utilization in PwHA switching from rFVIII to rFVIIIFc. METHODS: Data were collected for Taiwanese PwHA (severe-type) who switched from rFVIII to rFVIIIFc, including annualized bleeding rate (ABR) and weekly dose consumption 12 months pre-switch and > 6 months post-switch. RESULTS: The 51 patients were divided into 3 groups according to their pre-switch treatment: on-demand treatment, intermittent periodic prophylaxis, and regular prophylaxis. In every group, the post-switch median ABR was significantly reduced, with no significant differences between groups. Meanwhile, the post-switch median weekly dose of each group was significantly increased. In 32 patients on pre-switch prophylaxis, switching brought a further reduction in median ABR, associated with a significant increase in median weekly dose. No adverse effects or novel inhibitor development were seen. CONCLUSION: This is the first report from Asia on real-world experience of rFVIIIFc, showing that switching to rFVIIIFc prophylaxis led to further reduction in ABR and increase in weekly dose for all patient groups, even those on pre-switch rFVIII prophylaxis.

Clinical Predictors and Prediction Models for rFVIII-Fc Half Life in Real-World People with Severe Hemophilia A.

The half life of recombinant factor VIII-Fc (rFVIII-Fc) for people with hemophilia A (PwHA) varies greatly. Understanding the factors influencing the variation and assessment of rFVIII-Fc half life is important for personalized treatment. Eighty-five severe-type PwHA with rFVIII-Fc treatment receiving an evaluation of half life by the Web-Accessible Population Pharmacokinetic (PK) Service-Hemophilia during 2019-2021 were retrospectively enrolled. The 50-patient PK profiles before 2021 were used for analysis and developing prediction models of half life, and the 35-patient PK profiles in 2021 were used for external validation. The patients in the development cohort were aged 8-64, with a median rFVIII-Fc half life of 20.75 h (range, 8.25-41.5 h). By multivariate linear regression analysis, we found two, four, and five predictors of rFVIII-Fc half life for the blood groups non-O, O patients, and overall patients, respectively, including baseline VWF:Ag, BMI, VWF:activity/VWF:Ag ratio, body weight, O blood group, inhibitor history, HCV infection, and hematocrit. The three prediction equations of rFVIII-Fc half life (T) were respectively developed as T for non-O group patients = -0.81 + 0.63 × (BMI, kg/m2) + 6.07 × (baseline VWF:Ag, IU/mL), T for O group patients = -0.68 + 13.30 × (baseline VWF:Ag, IU/mL) + 0.27 × (BW, kg) - 1.17 × (BMI, kg/m2) + 16.02 × (VWF:activity/VWF:Ag ratio), and T for overall patients = -1.76 + 7.24 × (baseline VWF:Ag, IU/mL) - 3.84 × (Inhibitor history) + 2.99 × (HCV infection) - 2.83 × (O blood group) + 0.30 × (Hct, %), which explained 51.97%, 75.17%, and 66.38% of the half life variability, respectively. For external validation, there was a significant correlation between the predicted and observed half lives in the validation cohort. The median half life deviation was +1.53 h, +1.28 h, and +1.79 h for the equations of non-O group, O group, and overall group patients, respectively. In total, eight predictors influencing rFVIII-Fc half life were identified. Prediction equations of rFVIII-Fc half life were developed for the non-O and O blood groups and overall PwHA with a good degree of external validation. The equations could be applied to patients aged 8-64 without the need for PK blood sampling and clinically valuable for personalized therapy.

A case series and literature review on 98 pediatric patients of germ cell tumor developing growing teratoma syndrome.

INTRODUCTION: Malignant germ cell tumors (MGCTs) can develop either extracranially or intracranially. Growing teratoma syndrome (GTS) may develop in these patients following chemotherapy. Reports on the clinical characteristics and outcomes of GTS in children with MGCTs are limited. METHODS: We retrospectively collected the data, including the clinical characteristics and outcomes of five patients in our series and 93 pediatric patients selected through a literature review of MGCTs. This study aimed to analyze survival outcomes and risk factors for subsequent events in pediatric patients with MGCTs developing GTS. RESULTS: The sex ratio was 1.09 (male/female). In total, 52 patients (53.1%) had intracranial MGCTs. Compared with patients with extracranial GCTs, those with intracranial GCTs were younger, predominantly boys, had shorter intervals between MGCT and GTS, and had GTS mostly occurring over the initial site (all p < 0.001). Ninety-five patients (96.9%) were alive. However, GTS recurrence (n = 14), GTS progression (n = 9), and MGCT recurrence (n = 19) caused a substantial decrease in event-free survival (EFS). Multivariate analyses showed that the only significant risk factors for these events were incomplete GTS resection and different locations of GCT and GTS. Patients without any risk had a 5-year EFS of 78.8% ± 7.8%, whereas those with either risk had 41.7% ± 10.2% (p < 0.001). CONCLUSION: For patients with high-risk features, every effort should be made to closely monitor, completely remove, and pathologically prove any newly developed mass to guide relevant treatment. Further studies incorporating the risk factors into treatment strategies may be required to optimize adjuvant therapy.

Allele-specific polymerase chain reaction can determine the diplotype of NUDT15 variants in patients with childhood acute lymphoblastic Leukemia.

Mercaptopurine intolerance is an adverse effect of mercaptopurine administration in pediatric patients with acute lymphoblastic leukemia (ALL). NUDT15 variants have emerged as major determinants of mercaptopurine intolerance, especially in the Asian population. Two variants, c.55_56insGAGTCG in exon 1 and c.415C > T in exon 3, were commonly detected in the same allele, named NUDT15*1/*2. Although rare, compound heterozygous mutations also occur, with the two variants on different alleles (NUDT15*3/*6), which may confer tolerance to considerably lesser mercaptopurine dosage. Sanger sequencing or pyrosequencing can determine the NUDT15 variants but not the phase. Here, we designed an allele-specific PCR (AS-PCR) with locked nucleic acid-modified primers. A cohort of 63 patients harboring heterozygous c.55_56insGAGTCG and c.415C > T NUDT15 variations was selected for haplotyping using AS-PCR. Of the 63 patients, 60 harbored the NUDT15*1/*2 variant and three harbored compound heterozygous mutations, including two NUDT15*3/*6 and one NUDT15*2/*7 variants. These findings suggest that AS-PCR can determine NUDT15 diplotype and identify patients with compound heterozygous NUDT15 variants, which may enable precise genetic diagnosis of NUDT15. Nevertheless, a larger clinical trial is required to understand the clinical significance of NUDT15*3/*6 in pediatric patients with ALL because of its low incidence rate and challenges in detecting this variant.

Hypoalbuminaemia is an independent predictor for hemophagocytic lymphohistiocytosis in childhood Epstein-Barr virus-associated infectious mononucleosis.

BACKGROUND: Hemophagocytic lymphohistiocytosis (HLH) is a potentially fatal condition in children with Epstein-Barr virus (EBV)-associated infectious mononucleosis (IM). This study aimed to identify commonly available clinical and laboratory predictors that might help clinicians decide to perform the bone marrow and immunological tests for HLH in paediatric EBV-associated IM. METHODS: A retrospective case-control study of patients aged <18 yr diagnosed with EBV-associated IM and HLH from 1991 to 2010 in a tertiary medical centre was conducted. A diagnosis of HLH was defined as fulfilling the criteria of the guidelines of the HLH-2004 protocol of the Histiocyte Society and consisted of at least evidence of hemophagocytosis in a bone marrow biopsy. RESULTS: A total of 177 IM and 27 HLH patients were enrolled. The mean age was 5.3 yr with a female-to-male ratio of 1.06. The most common characteristics (>70% of patients) were fever, lymphadenopathy and hepatomegaly. In addition to the diagnostic criteria of HLH including fever, splenomegaly, cytopenia, hyperferritinaemia, hypertriglyceridemia and/or hypofibrinogenaemia, children with HLH had a significantly higher rate of prolonged fever >10 d, hepatomegaly, jaundice, general malaise, elevated aspartate aminotransferase, lactate dehydrogenase, C-reactive protein and hypoalbuminaemia compared to those with IM (all P < 0.01). Multiple logistic regression confirmed that hypoalbuminaemia (OR = 23.1, P = 0.01) was an independent predictor of paediatric HLH, with a high sensitivity (96%) and a good negative likelihood ratio (0.06) in patients with EBV-associated IM. CONCLUSIONS: Hypoalbuminaemia is a unique characteristic and potentially a valuable predictor for HLH in paediatric EBV-associated IM.

Absence of biallelic TCRγ deletion predicts induction failure and poorer outcomes in childhood T-cell acute lymphoblastic leukemia.

BACKGROUND: The absence of biallelic TCRγ deletion (ABD) is a characteristic of early thymocyte precursors before V(D)J recombination. The ABD was reported to predict early treatment failure in T-cell acute lymphoblastic leukemia (ALL). This study aimed to investigate its prognostic value in Taiwanese patients with T-cell ALL. PROCEDURE: Forty-five children with T-cell ALL were enrolled from six medical centers in Taiwan. Quantitative DNA polymerase chain reaction (Q-PCR) was performed to check the status of TCRγ deletion. The threshold for homozygous deletions by Q-PCR was defined as a fold-change <0.35. RESULTS: ABD was found in 20 patients [20:45] who had higher incidences of induction failure than those without ABD (P = 0.03; hazard ratio [HR] = 8.13; 95% confidence interval [95% CI] = 1.23-53.77) after multivariate regression analysis. Patents with ABD also had inferior EFS and OS (P = 0.071 and 0.0196, respectively). Multivariate Cox analysis indicated that the association between ABD and overall survival was independent of age and leukocyte count on presentation (P = 0.036; HR = 4.25; 95% CI = 1.10-16.42). CONCLUSIONS: The absence of TCRγ deletion is a predictor of a poor response to induction chemotherapy for pediatric patients with T-cell ALL in Taiwan. Providing patients with T-cell ALL and ABD with alternative regimens may be worthwhile to test in future clinical trials.