In vivo cell cycle characteristics of pediatric leukemia patients.

: Following i.v. bromodeoxyuridine infusion, a double-label technique using in vitro tritiated thymidine was used to determine the labeling index (LI), duration of S-phase (Ts), and cell cycle time (Tc) in pediatric leukemia patients. Eleven patients with acute lymphoblastic leukemia (ALL) and six patients with acute nonlymphoblastic leukemia (ANLL) were studied. Results of cell cycle kinetic studies are given for each group. Although median values for AML and ALL patients are similar to values reported in previous studies, there is a wide range of values among individual patients. The variation among the kinetic properties of blast cells in these patients reflects the heterogeneity of the acute leukemias of childhood. Further studies will be done to determine if these parameters correlate with outcome of therapy for pediatric leukemia patients.