In a nutshell
The study reported the outcomes of children with non-T cell acute lymphoblastic leukemia (ALL) treated with risk-adjusted therapy. The main finding was that patients with standard-risk (SR) ALL had improved survival without cancer-related events.
Some background
ALL-97 was the first clinical trial performed on Japanese children with ALL. However, the benefits of ALL-97 in children with SR-ALL were unsatisfactory compared with the following trials from western countries.
It was estimated that preventative cranial irradiation therapy (pCRT) to prevent brain recurrence had contributed to poorer outcomes in ALL-97. Therefore, it is important to evaluate the safety and effectiveness of modifying treatments according to disease risk. This may involve avoiding pCRT which has long-term toxic side effects and intensifying chemotherapy.
Methods & findings
This study was conducted on 1138 children with non-T cell ALL. Patients were divided into 3 groups – standard-risk (SR), high-risk (HR), and extremely high-risk (ER). This was based on patients’ age, white blood cell count, cancer genetic defects, and treatment response. There were 456 SR, 543 HR, and 139 ER patients. PCRT was only performed on patients whose cancer had spread to the brain. Patients were followed-up for 6.6 years on average.
All clinical symptoms of cancer were gone (complete response) in 96.4% of patients. Event-free survival (EFS) for 4 years was achieved in 85.4% of patients. EFS means how long patients survive without having cancer-related events. EFS at 8 years was 82%. Overall, 91.2% of patients survived after 4 years and 88.6% after 8 years.
On average, 15.9% of patients faced relapse at 4 years. Relapse rates were 8.7% for SR, 13.4% for HR and 30.4% for ER patients. A total of 9 patients experienced a relapse in the brain and 7 had a relapse in both brain and bone-marrow.
When compared to the ALL-97 trial the 4-year EFS rates were improved from 81.3% to 88.2% in SR-ALL patients by risk-adjusted therapy. However, treatment outcomes were not largely improved in HR patients.
The bottom line
The authors concluded that risk-adjusted therapy improved the outcomes of children with SR-ALL.
The fine print
The study was performed on children in Japan only. The number of leukemic cells left in the blood after therapy was also not assessed.
Published By :
Blood cancer journal
Date :
Feb 27, 2020
