1. Department of Neurosurgery, Children’s Hospital “Agia Sofia,” Athens, Greece
2. Department of Pathology, Children’s Hospital “Agia Sofia,” Athens, Greece
3. Haematology Laboratory, Unit of Molecular Biology, University Hospital of Ioannina, Ioannina, Greece
4. Hematology Oncology Unit of 1st Department of Pediatrics of Athens University, Athens, Greece