Katarzyna Musioł

Imatinib in the treatment of chronic myeloid leukemia in children and adolescents is effective and well tolerated: Report of the Polish Pediatric Study Group for the Treatment of Leukemias and Lymphomas

BACKGROUND Chronic myeloid leukemia (CML) constitutes only 2-3% of all leukemias in pediatric patients. Philapelphia chromosome and BCR-ABL fusion are genetic hallmarks of CML, and their presence is crucial for targeted molecular therapy with tyrosine kinase inhibitors (TKIs), which replaced hematopoietic stem cell transplantation (HSCT) as a standard first-line therapy. The disease in pediatric population is rare, and despite molecular and clinical similarities to CML in adults, different approach is needed, due to the long lifetime expectancy and distinct developmental characteristics of affected children. OBJECTIVES The objective of this study is to evaluate treatment with imatinib in Polish pediatric patients with CML. MATERIAL AND METHODS We analyzed the results of treatment with imatinib in 57 pediatric patients (June 2006 - January 2016) from 14 Polish pediatric hematology and oncology centers. RESULTS In the study group, 40 patients continued imatinib (median follow-up: 23.4 months), while in 17 the treatment was terminated (median follow-up: 15.1 months) due to therapy failure. In the latter group, 13 patients underwent HSCT, while 4 switched to second-generation TKIs. The 5-year overall survival rate (OS) in the study group was 96%, and the 5-year event-free survival (EFS) was 81%. CONCLUSIONS Our results confirm that the introduction of TKI therapy has revolutionized the treatment of CML in the pediatric population by replacing the previous method of treatment with HSCT and allowing a high percentage of OS and EFS.

Serum levels of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in children with brain tumours

BACKGROUND Angiogenesis is the process of new vessel formation originating from the existing vascular network. It plays an important role in the growth and spread of malignancies, including brain tumors. The process of angiogenesis is characterized by increased expression of vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF), and by the release of their soluble forms into circulation. OBJECTIVES The aim of the study was to evaluate serum levels of VEGF and bFGF in children with malignant and benign brain tumors. MATERIAL AND METHODS The study group (group N) included 106 children diagnosed with brain tumors. The children in group N were classified according to tumor pathology into 3 subgroups: N1 (n = 63): patients with malignant tumors, excluding anaplastic astrocytoma (AA) and glioblastoma multiforme (GBM); N2 (n = 25): patients with benign tumors; and N3 (n = 18): patients with high grade gliomas (AA and GBM). VEGF and bFGF were determined by ELISA in blood samples before the initiation of chemotherapy. VEGF and bFGF levels were compared within the subgroups in relation to tumor grading and the extent of surgery. RESULTS The median VEGF in patients with brain tumors was significantly higher than in the control group. The median levels of VEGF and bFGF in subgroup N1 were significantly higher than in the control group. The differences in VEGF and bFGF concentrations between the subgroups in relation to the extent of tumor resection were not significant. CONCLUSIONS Significantly higher plasma VEGF levels in children with brain neoplasms may reflect enhanced angiogenesis in the tumors.

Rhabdomyolysis: rare complications with a difficult prognosis in the course of anticancer treatment.

Rhabdomyolysis refers to a number of clinical and biochemical symptoms, which result from the destruction of skeletal muscles. The following triad of symptoms is considered typical: myalgia, muscle weakness, and dark urine. The most common reasons for rhabdomyolysis in children are infections. It has also been reported that rhabdomyolysis may be caused by chemotherapy drugs. The most difficult complication of rhabdomyolysis is renal failure. The authors present a 17-year-old boy diagnosed with Ewing sarcoma and a 16-year-old boy suffering from acute leukemia, both with rhabdomyolysis developed in the course of infection caused by Clostridium difficile, and drug-induced neutropenia.

PROANGIOGENIC CYTOKINES VASCULAR-ENDOTHELIAL GROWTH FACTOR AND BASIC FIBROBLST GROWTH FACTOR IN CHILDHOOD LYMPHADENOPATHY

Increased angiogenesis is observed both in the inflammatory and in the neoplasmatic tissue. The aim of the study was to assess the diagnostic significance of serum concentration of vascular-endothelial growth factor (sVEGF) and basic fibroblast growth factor (sbFGF) in the various forms of lymphadenopathy in children. Ninety-four children with lymphadenopathy were studied: group A, 52 patients with lymphadenitis; group B, 42 patients with lymphomas. Group B was divided into subgroups: BP, children with lymphomas in peripheral lymph nodes and BM, children with lymphomas in peripheral lymph nodes and mediastinal tumor. The healthy control group was 20 children. Using enzyme-linked immunosorbent assays the authors quantified VEGF and bFGF in serum of healthy children and of children with lymphadenopathy. The sVEGF in group A was significantly higher than controls (313.8 versus 44.6 pg/mL; P <.05) and in group B was 633.4 pg/mL and was significantly higher than controls (P <.0001). The sVEGF and bFGF in group A versus subgroup BP were significantly lower (PVEGF <.05, PbFGF <.05), and sVEGF in subgroup BP versus BM was significantly lower (P <.05). These results show that the evaluation of serum VEGF concentration might be useful as noninvasive diagnosis of some chronic peripheral lymphadenopathies in children.