Potential conflict of interest
Disclosure forms provided by the authors are available with the full text of this article at www.informahealthcare.com/lal.
Appendix
The PPLLSG investigators include Iwona Malinowska, Michał Matysiak (Department of Pediatric Hematology and Oncology, Medical University of Warsaw), Jerzy R. Kowalczyk, Monika Lejman (Department of Pediatric Hematology and Oncology, Medical University, Lublin), Katarzyna Derwich, Jacek Wachowiak (Department of Pediatric Hematology, Oncology and Transplantology, University of Medical Sciences, Poznań), Joanna Trelińska, Wojciech Młynarski (Department of Pediatric Oncology, Hematology and Diabetology, Medical University, Łódź), Grażyna Sobol (Department of Pediatrics, Medical University of Silesia, Katowice), Katarzyna Muszyńska-Rosłan, Maryna Krawczuk-Rybak (Department of Pediatric Oncology, Medical University, Białystok), Wanda Badowska (Regional Specialistic Pediatric Hospital, Olsztyn), Maciej Niedźwiecki, Anna Balcerska (Department of Pediatric Hematology, Oncology and Endocrinology, Medical University, GdanńLsk), Maria Wieczorek (Chorzów Center of Pediatrics and Oncology, Chorzów), Tomasz Ociepa, Tomasz Urasiński (Department of Pediatrics, Hematology and Oncology, Pomeranian Medical University, Szczecin) and Renata Tomaszewska (Department of Pediatric Hematology and Oncology, Medical University of Silesia, Zabrze).