Results of Intensive Chemotherapy of Acute Myeloblastic Leukemia in Children According to the Berlin-Frankfurt-Münster Strategy: A Single-Institution Trial

Abstract

In order to improve the poor results of treatment of childhood acute myeloblastic leukemia (AML), we applied the Berlin-Frankfurt-Münster (BFM) strategy for patients with AML admitted to the clinic of our institute. The reference group included 29 patients treated with courses “7+3” and “5+2” (conventional doses of cytosine arabinoside, ara-C, and daunorubicin). The results of this treatment were as follows: remission was achieved in 58.6% of patients relapse-free survival at 42 months was 21.4%. Between February 1990 and May 1994, a total of 46 consecutive patients with AML were treated according to the BFM strategy (complication from AML-BFM-83 and AML-BFM-87 studies); there were 17 males and 29 females. Mean age was 8 years (range 1-15 years). The French-American-British (FAB) subtype distribution was as follows: MO-4.25%, Ml-6.45%, M2-19.1% M3-10.65%, M4-23.4%, M5-27.75%, M6-6.4%. All patients received an 8-day induction course: conventional doses of ara-C, daunorubicin 30 mg/m² daily-six doses, and etoposide 150 mg/m² a day–three doses. A sixdrug (prednisolone; 6-mercapto-purine, 6-MP; vincristine; ara-C, cyclophosphamide; doxorubicin) consolidation course lasted 6 weeks. Twenty three patients received intensification therapy: 20 patients with high doses of ara-C plus etoposide and three patients with high-dose ara-C plus mitoxantrone. Twelve patients did not receive an intensification course. CNS prophylaxis included ara-C intrathecally and cranial gamma-irradiation (18 Gy). As a result of the treatment 35 patients (76%) achieved complete remission (CR). There were 11 induction failures: the toxic deaths (13%) and five primary refractory disease (10%). One patient died in CR after the intensification course. Of 34 patients completing the intensive phase of therapy, five patients relapsed (15%). The actuaial event-free survival is 63% at 51 months.

In conclusion our cohort of AML patients is characterized by a peculiar distribution of FAB subtypes with a prevalence of M4 and M5 subtypes needing intensive regimens of therapy. The BFM strategy of intensive treatment showed high efficacy in the presented group of patients with AML.