Comparison of risk grouping methods for acute lymphoblastic leukemia in children

Four criteria for the risk grouping of children's acute lymphoblastic leukemia: Children's Cancer and Leukemia Study Group (CCLSG) in Japan, Southwest Oncology Group (SWOG) and Children's Cancer Study Group (CCG-141) in the USA, Berlin-Frankfurt-Münster Study Group (BFM) in West Germany, were applied retrospectively to 109 patients with the disease who had been treated randomly in Sapporo National Hospital from 1978 to 1986. No significant difference in respect of survival curve was found in most combinations between low- and intermediate-risk groups, nor among either low- or intermediate-risk groups (P greater than 0.10, Cox-Mantel's test). Among the four high-risk groups formed by the application of these criteria, no significant difference was noted (P greater than 0.10), but there were significant differences between the high-risk and the low- or intermediate-risk groups (P less than 0.05 or 0.10). With such results, a comparison of therapeutic results in high-risk groups yielded by different study groups would appear to be not only possible but useful, for example, in improving therapeutic methods.