Thromboembolism is one of the most common complications during induction therapy of pediatric acute lymphoblastic leukemia (ALL). Procoagulant microparticles in the circulation may cause thromboembolic events. The aim of our study was to determine the levels of apoptotic, platelet-derived, endothelial-derived, and tissue factor-positive microparticles of children with ALL at diagnosis and during induction therapy.
Sixteen precursor B-cell ALL cases and 30 healthy children between 1 and 18 years of age were included. Microparticle levels were analyzed from peripheral blood samples at initial diagnosis, on days 12 and 13 (before and after the first L-asparaginase administration), and on day 33 of ALL-BFM 2000 treatment protocol. Microparticle levels were analyzed by using flow cytometry.
At initial diagnosis, platelet, endothelial-derived, and tissue factor-positive microparticle levels were significantly high in children with ALL. They increased significantly after prednisone and L-asparaginase administration. Apoptotic microparticle levels were not elevated at diagnosis, but remained high during all induction therapy period. None of the patients had evidence of thromboembolism during induction therapy.
Our study demonstrated that children with ALL have increased levels of apoptotic, platelet-derived, endothelial-derived, and tissue factor-positive microprticles during induction therapy. Further studies are needed in larger groups of patients in order to evaluate the risk of elevated microprticles for development of thromboembolism during induction therapy period in children with ALL.
aDepartment of Pediatric Hematology, Dokuz Eylül University Faculty of Medicine
bDepartment of Medical Oncology, Dokuz Eylül University Institute of Oncology, İzmir, Turkey
Correspondence to Dr Hale Ören, MD, Professor, Department of Pediatric Hematology, Dokuz Eylül University Faculty of Medicine, 35340 Balcova, Izmir, Turkey. Tel: +90 532 6669050; fax: +90 232 4126005; e-mail: email@example.com
Received 11 April, 2019
Revised 12 April, 2019
Accepted 12 April, 2019