Risk stratification
Patients were enrolled in the high risk (HR) group if they had an
initial white blood cell (WBC) count of > 50 000/ul, were
aged < 1 year or > 10 years, had initial
CNS-involvement, had a mediastinal mass on the initial chest x-ray, had
more than 1000 lymphoblasts/mm3 in the peripheral
blood after the first week of monotherapy or no remission in the bone
marrow after induction on day 36. All other patients were stratified
into the SR group (table 2). The main differences in the treatment
between the two groups were additional applications of daunorubicin
during induction and maintenance and higher doses of cytarabine in the
intrathecal therapy during induction, consolidation and maintenance in
the HR group.