Treatment for childhood acute myeloid leukaemia (AML) consists of remission induction chemotherapy followed by postremission chemotherapy with or without bone marrow transplantation. The AML Berlin-Frankfurt-Munster (BFM)-83 protocol with induction-consolidation-maintenance chemotherapy for 2 years has been reported to result in a 6-year event-free survival (EFS) and event-free interval (EFI) of 49% and 61% respectively. A total of 174 Malaysian children were treated with this protocol between 1985 and 1999. The 5-year EFS and EFI was 30.7% and 48.0% respectively. The overall mortality from sepsis was 24%, which needs urgent address. The 5-year EFS for patients treated before 1993 and after 1993 was 18.6% and 41.3%, respectively (P = 0.04), while the EFI was 32% and 60.6% respectively (P = 0.034). The improvement seen after 1993 was related to a reduction in induction deaths for that period and probably reflected increased capability and familiarity to cope with the demands of the AML-BFM-83 protocol and accompanying complications in the treatment of AML.
Reports on the outcome of treatment in ALL in Asian (non-Caucasian) adults have been few, and published results compare very unfavourably with results of treatment from 'Western' centres. Seventy-four newly diagnosed Malaysian patients with ALL between the ages of 15 and 69 were treated from 1986 to 1990. The clinical features and prognostic factors were similar to those reported in 'Western' series. The chemotherapy protocol utilized was adapted from the one used by Hoelzer et al in the multicentre German study. The complete remission rate was 73%. The probability of continuous complete remission at 5 years was 29% with a median duration of remission of 15 months. This compares with Hoelzer's initial results of 77% CR rate and 35% CCR at 5 years. Patients with an initial white cell count of less than 30 x 10(9)/l at presentation were found to have a significantly better disease-free survival than those with a count of more than 30 x 10(9)/l (35 vs 22%, P = 0.026, univariate analysis). There was no difference in leukaemia-free survival according to age, sex, ethnic group, or immunophenotype. These results show that the use of moderately intensive chemotherapy protocols in Asian (non-Caucasian) patients achieves similar results to those used in Caucasians. We also showed that the difficulties in 'curing' approximately 70% of adult patient with ALL are universal.
Signal transduction pathways are constitutively expressed in leukaemic cells resulting in aberrant survival of the cells. It is postulated that in cells of chemo-sensitive patients, chemotherapy induces apoptotic signals leading to cell death while survival signals are maintained in cells of chemo-resistant patients. There is very little information currently, on the expression of these mediators in patients immediately after chemotherapy initiation. We examined the expression pattern of proinflammatory cytokines, signaling molecules of the PI3K and MAPK pathways molecules and death receptor, DR5 on paired samples at diagnosis and during chemotherapy in acute myeloid leukaemia patients treated with cytosine arabinoside and daunorubicin. The results were correlated with remission status one month after chemotherapy. We found that in chemo-sensitive patients, chemotherapy significantly increased the percentage of cases expressing TNF-alpha (p = 0.025, n = 9) and IL-6 (p = 0.002, n = 11) compared to chemo-resistant cases. We also observed an increased percentage of chemo-sensitive cases expressing DR5 and phosphorylated p38, and Jnk. Thus, expression of TNF-alpha, IL-6, DR5, phospho-p38 and phospho-Jnk may regulate cell death in chemo-sensitive cases. In contrast, a significantly higher percentage of chemo-resistant cases expressed phospho-Bad (p = 0.027, n = 9). IL-beta and IL-18 were also found to be higher in chemo-resistant cases at diagnosis and during chemotherapy. Thus, expression of various cellular molecules in leukaemic blasts during chemotherapy may be useful in predicting treatment outcome. These cellular molecules may also be potential targets for alternative therapy.