Abstract

Of 328 children who were diagnosed as acute lymphoblastic leukemia at the Department of Pediatrics. Seoul National University Hospital from Jan., 1978 through Dec., 1987, 211 patients above one year af age were evaluable for induction chemotherapy. The leukemias were classified as standard risk (SR), comparison group (who had high-risk prognostic factors, but had been treated with standard regimen), or high- risk (HR) leukemia according to the prognostic criteria at diagnosis. Three regimens were compared and the results were as follows. 1) The complete remission (CR) rate was 97.1%(133/137), 81.0%(34/42) and 90.6%(29/32) in SR, comparison group. and HR group, respectively. And significant difference in the CR rate was seen between SR group and comparison group (p= 0.0001). 2) Of the patients remained in remission follow-up of each group showed 56.8% 5-yr disease-free survival (DFS)(+-5.9%, median follow-up 30 mo) in SR, 35.5% (+-9.1%, median 24 mo) in comparison group, and 76.0%(+- 8.5%, median 24 mo) in HR group. And significant difference in the 5yr-DFS rate were observed be(ween SR and comparison group (P = 0.007), between HR and comparison group (p = 0.002), respectively. 3) Induction failure was due to infection (n=2) bleeding (n=1) or uric acid nephropathy (n= 1) in SR drug resistance (n=3), infection (n=2), bleeding (n=2), or combind infection and bleeding (n=1) in comparison group, and bleeding (n=2) or infection (n= 1) in HR. Of the patients who were on maintenance chemotherapy in complete remission, 11 died due to infection: menigitis or meningoencephalitis (n=4), disseminated varicella (n=3), Pneumocystis carinii pneumonia (n=2), and sepsis (n=2). 4) In SR group, 29 patients experienced relapse: BM(n=18), CNS(n=3), BM and CNS(n=4), and testes (n=4). Two- third (n = 19) of them relapsed between 6mo to 2yr after initial remission. In comparison graup, 20 relapsed: BM (n= 10), CNS(n=2), BM and CNS (n=3), testes (n=4), and testes and CNS(n =1), Mostly they relapsed within the first 2 years after remission. In HR group, all patients (BM 3 and CNS 1) experienced relapse from 1 yr to 1 1/2 yr after initial remission.

• Keywords: Acute Lymphoblastic Leukemia, Chemotherapy, Induction Remission Rate, Event Free Survival Rate