Treatment of Acute Nonlymphoblastic Leukemia in Childhood: Results of protocol ANLL-827 and ANLL-861 studies

Abstract

Sixty-five evaluable children with acute nonlymphoblastic leukemia (FAB categoies: M1, M2, M4, M5) entered into the protocol studies of Children's Cancer and Leukemia Study Group (CCLSG) between February, 1981 and December, 1985. Before October, 1984, 49 cases were treated with protocol ANLL-827; Regimen-I (neo-MINI-COAAP therapy) or Regimen-II (BH-AC DMP therapy). After November 1984, 16 cases were treated with a new protocol ANLL-861 (combined therapy of Regimen-I and II). Three protocol regimens with multi-drug chemotherapy were administered for three years, without aggressive CNS prophylaxis.
Fifty of 65 children (76.9%) achieved complete remission (CR). There was no difference in CR rate among three protocol-regimens. The rates of cotinuous complete remission (CCR) at 20 months were 40.5%, 18.8%, and 72.7%, respectively in Regimen-I, Regimen-II, and ANLL-861. However, statistically there was no difference in CCR rate among the protocol-regimens. The median duration of CCR was 11.2 months and 18.8 months in Regimen-I and II. Seven patients have been off chemotherapy, and 6 cases of them have remained in CCR. The incidence of CNS involvement with the three protocol-regimens was 9.2% (6/65). A high incidence of CNS involvement occurred in patients with M4 and M5. CR duration in patients with monocytic leukemia (M4, M5) was significantly shorter (P<0.01) than that in patients with M1 or M2.
These results indicate that current treatment regimens improve prognosis for acute nonlymphoblastic leukemia in childhood.