Incidence of bacteremias and invasive mycoses in children with high risk neuroblastoma

Background. Information on the incidence of infectious complications during for treatment for high risk neuroblastoma (HR-NB) is limited. Bacteremias and invasive mycoses may be considered surrogate markers of the infection burden. Patients and Methods. Data on bacteremias and invasive mycoses occurring during 3 consecutive protocols for front line (NB-89; NB-92; NB-97) or salvage therapy (TVD) for HR-NB were reviewed. The cumulative risk of developing a first episode and the rate of infections during the entire length of each protocol were evaluated. Results. Front line protocols were given to 80 patients for a total of 22,070 days at risk; salvage treatment was given to 24 children for 2,909 days at risk. During front line therapy 41 infectious episodes were diagnosed in 29 (36%) patients, for a 45% cumulative risk and an infection rate (IR) of 0.19/100 patient-days-at risk. Salvage therapy determined five infectious episodes in four (17%) patients, with a 39% cumulative risk, and an IR of 0.17. The IR during the phase of high dose chemotherapy with hematopoietic stem cell rescue (megatherapy) included in the three front line protocols decreased over time (1.54 in NB-89; 0.52 in NB-92 and 0.0 in NB 97; P= 0.001), possibly because of the use of less aggressive conditioning regimens, without radiotherapy. Conclusions. The IRs of protocols for HR-NB did not change over time. The megatherapy-related phases are those at highest risk.