Fig. 1From: Increased plasma concentration of cell-free DNA precedes disease recurrence in children with high-risk neuroblastomaPlasma cfDNA levels in NB patients with or without recurrence during maintenance treatment. Data are presented as the median ± standard deviation of the last measurement before recurrence diagnosis (n = 36) or of all measurements throughout maintenance treatment for the recurrence-free group. Each symbol represents an individual patient, p < 0.05 by the Mann–Whitney U testBack to article page