Results of acute lymphoblastic leukemia treatment in children in the Slovak Republic

Abstract

Treatment of childhood acute lymphoblastic leukemia (ALL) according to the 1st Slovak protocol started in the Slovak Republic in 1971 in eight pediatric departments. Gradually, two other protocols were written, and 496 children were treated with these three protocols from 1971 to 1992. Since 1992, all children have been treated in three pediatric oncological departments. From 1992 to 1996, protocols for standard and high-risk ALL were developed that were used for 111 children in Bratislava, while the centres in Banska Bystrica and Košice had started to use BFM protocols. Since 1997, all patients with ALL have been treated according to ALL BFM 95, and since 2002, they have been included in the ALL IC BFM 2002 study. We evaluated treatment results in the standard arm of ALL BFM 95 and compared it with previous Slovak protocols. Rates of complete remission increased from 90.6% in the fi rst Slovak protocol to 97.1% in BFM 95; EFS and OS increased from 0.46 and 0.50 to 0.67 and 0.72, respectively. Relapse rates decreased from 42% to 20.5%. EFS was signifi cantly worse in children with leukocyte counts >100 × 10 9 /l and in the HR group in comparison to standard-and medium-risk groups. OS was also signifi cantly worse in T-cell ALL than in B-cell ALL. Death rates in the 1st complete remission decreased gradually in the Slovak protocols from 10.4% to 1.8%, but were high in BFM 95 (10.8%) due to more intensive therapy and initial unsatisfactory experiences with BFM protocols. All parameters improved in the ALL IC BFM 2002 study.

Improved outcome for children and adolescent with acute lymphoblastic leukemia in the first decade of the 21st century: A report from the Slovak Republic

“…Initially from 1997-2001, the ALL BFM 95 regimen was adopted and children were treated with this regimen in all of the three centers in the Slovak Republic, but not as part of a formal clinical trial. The 10-year EFS and OS rates from this period were 67% and 72%, with 2.9% induction deaths and 10.8% deaths in 1 st CR, and a 20% relapse rate [16]. In order to participate in the formal ALL IC-BFM 2002 trial, several important steps were taken including standardized methods for diagnosis and treatment response, development of a common database to facilitate country-wide randomization and data capture, and institution of standardized supportive care guidelines across the three centers.…”

“…Each year in the Slovak Republic, which has about 1.1 million children, approximately 40 pediatric leukemia cases are diagnosed, including 30 cases of acute lymphoblastic leukemia, 6-8 cases of acute myeloid leukemia, and 1-2 cases of chronic myeloid leukemia [16,23,24]. Children with leukemia are treated in 3 centers, which are well distributed across Slovakia.…”

“…From 1971 until 1991, a variety of different treatment regimens derived from those used in the United States were used to treat children with ALL [13,14,15]. The 10-year EFS and OS rates in this period were 46% and 50%, respectively [16]. Starting in 1997, BFM-based ALL treatment regimens have been used.…”

“…However, we encountered higher rates of death in 1 st CR. Prior to 1997, the rate of death in 1 st CR decreased gradually in Slovak protocols from 10.4% to 1.8%, but then significantly increased (10.8%) with introduction of the ALL BFM 95 protocol in Slovakia in 1997 due to insufficient experience with intensive BFM-type therapy (16). Since 2002, the cumulative incidence of death in 1 st CR decreased to 4.6%, which is still about two times higher than the results of ALL BFM 95 (2.1%) and three times higher than current achievements of leading international collaborative ALL treatment groups (1.4%) (27).…”

“…[13,14,15]. In 1995 the ALL BFM 90 protocol was gradually introduced and since 1997 all three departments of paediatric oncology treated children and adolescents with ALL following the ALL BFM 95 protocol, which formed the basis of the ALL IC-BFM 2002 trial [16].The …”