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Child Cancer Fund subsidises statistical research

Marta Fiocco, professor in the Mathematical Institute, has received a grant for analysing data on chemotherapy in children suffering from leukaemia. The work involves developing and applying new statistical methods that will help determining the optimal dose of chemotherapy.


Children with acute lymphoblastic leukaemia (ALL) receive chemotherapy  until two years after initial diagnosis. Setting a correct dose of the highly toxic substances administered is important, and hence the effects of different dose levels is monitored. However, such studies are complicated by the fact that in clinical practice the dose levels are continuously adjusted according to their effect on the blood cell counts and on the occurrence of clinical side effects, especially infections. These effects are not the target of the treatment but do correlate with the aim of the treatment, survival.


The novelty of the research project is to consider the interplay between patients’ toxicity and therapy modifications, making it possible to remove the biases inherent in a conventional statistical analysis. The final objective is to determine optimal dose levels for personalized care, and practical guidelines for ALL treatment.

The project will be carried out by Stéphanie van der Pas, assistant professor and Carlo Lancia, senior researcher in the statistics group at  the Mathematical Institute, in close collaboration with Prof Rob Pieters medical director Princess Maxima Center (Utrecht) and Dr. Hester de Groot  Dutch Childhood Oncology Group (Den Haag).  Statisticians at Leiden University have joined in offering a full program in statistical science, with medical applications as one of the focus points.