Additional flow cytometric studies for differential diagnosis between Burkitt lymphoma/leukemia and B-cell precursor acute lymphoblastic leukemia.

The differentiation between Burkitt lymphoma/leukemia (BL) and B-cell precursor acute lymphoblastic leukemia (BCP-ALL) is sometimes complicated. Laboratory findings that favor BL (e.g.

Heterogeneity of childhood acute leukemia with mature B-cell immunophenotype.

Background: Flow cytometry (FCM) plays a crucial role in the differential diagnosis of Burkitt lymphoma/leukemia (BL) and B-cell precursor acute lymphoblastic leukemia (BCP-ALL). The presence of surface IgM (sIgM) alone or with light chain restriction indicates a mature blast phenotype (BIV by EGIL) and is usually observed in BL. However, sIgM expression could also be detected in transitional BCP-ALL cases.

Bodyweight-adjusted rivaroxaban for children with venous thromboembolism (EINSTEIN-Jr): results from three multicentre, single-arm, phase 2 studies.

Background: Rivaroxaban has been shown to be efficacious for treatment of venous thromboembolism in adults, and has a reduced risk of bleeding compared with standard anticoagulants. We aimed to develop paediatric rivaroxaban regimens for the treatment of venous thromboembolism in children and adolescents.

Methods: In this phase 2 programme, we did three studies to evaluate rivaroxaban treatment in children younger than 6 months, aged 6 months to 5 years, and aged 6-17 years.

Rituximab and reduced-intensity chemotherapy in children and adolescents with mature B-cell lymphoma: interim results for 231 patients enrolled in the second Russian-Belorussian multicentre study B-NHL-2010M.

The value of adding rituximab to chemotherapy in children with aggressive B-cell non-Hodgkin lymphoma (B-NHL) is still insufficiently studied. We enrolled 231 patients [mean age 9 years old (range 2-17); male:female ratio 3·4:1] with Burkitt (BL, 179 patients, 76·7%), diffuse large B-cell (32 patients, 14%), primary mediastinal B-cell (14 patients, 6%), and other (6 patients, 2·6%) B-cell lymphomas in a prospective study of immuno-chemotherapy. Stages were I-II in 32% and III-IV in 68% of the patients.

Therapy of advanced-stage mature B-cell lymphoma and leukemia in children and adolescents with rituximab and reduced intensity induction chemotherapy (B-NHL 2004M protocol): the results of a multicenter study.

Pediatric mature B-cell non-Hodgkin lymphomas (B-NHLs) are highly aggressive malignant tumors that are curable with chemotherapy (ChT). High-dose methotrexate (MTX) is considered indispensable for successful treatment, but this therapy frequently induces severe mucositis and infectious complications, especially in induction, which can cause treatment failure. A prospective multicenter trial of combined immunochemotherapy for advanced-stage B-NHL with rituximab and the modified NHL-BFM-90 protocol was conducted.

TPMT genetic variations in populations of the Russian Federation.

Background: Polymorphisms that reduce the activity of thiopurine S-methyltransferase (TPMT) cause adverse reactions to conventional doses of thiopurines, routinely used for antileukemic and immunosuppressive treatment. There are more than 20 variant alleles of TPMT that cause decreased enzymatic activity. We studied the most common variant alleles of TPMT and their frequency distribution in a large cohort of multiracial residents in the Russian Federation and compared their frequencies in children with and without malignancy to determine whether TPMT gene abnormality is associated with hematologic malignancy.

Rapid genotyping of common deficient thiopurine S-methyltransferase alleles using the DNA-microchip technique.

Thiopurine drugs are metabolized, in part, by S-methylation catalyzed by thiopurine S-methyltransferase (TPMT). Patients with very low or undetectable TPMT activity are at high risk of severe, potentially fatal hematopoietic toxicity when they are treated with standard doses of thiopurines. As human TPMT activity is controlled by a common genetic polymorphism, it is an excellent candidate for the clinical application of pharmacogenetics.