In the present study the complication rate of Broviac catheters in the therapy of children with cancer was determined. Of special interest was the question of to what extent the incidence of bacteremias is increased by the implant. For this reason the method of matched pairs analysis was chosen comparing 55 patients with 61 catheters to 1 child each who received the therapy via peripheral veins. Apart from having the same disease, the same therapy protocol and the same age group the partners had a similar number of leukocytopenic days (leukocyte counts, < 1000/microliters) in the study period. The observation time was 9671 days in the catheter group and 9666 days in the control group. During this time 167 fever episodes (17.7 episodes/1000 days) were recorded in the patients with implant but only 133 episodes (14.0/1000 days) in the control patients. Study and control groups had similar frequencies of fever of unknown origin with leukocyte counts > or = 1000/microliters and fever with a known focus. However, 29 bacteremias (2.9 episodes/1000 days) represented a 4 times higher complication rate with the use of Broviac catheters than in the control group (7 bacteremias, 0.7 episode/1000 days). Episodes of fever of unknown origin with leukocytopenia were 1.5 times more common in the catheter group than in the control group. Although it is not possible to prove that the catheter played a role as focus of bacterial infection, an increased risk of infection must be supposed. The Broviac catheter meets with broad approval by the patients, parents and medical staff.(ABSTRACT TRUNCATED AT 250 WORDS)