What is the cure rate and relapse rate for childhood leukemia?

Childhood Leukemia Cure and Relapse Rates

The cure rate for childhood acute lymphoblastic leukemia (ALL) is approximately 80-90%, while acute myeloid leukemia (AML) has lower cure rates of 40-60%, with relapse occurring in approximately 15-20% of ALL cases and 30-40% of AML cases. 1, 2, 3

Acute Lymphoblastic Leukemia (ALL)

Cure Rates

• ALL represents 75-80% of acute leukemias in children 4
• Modern treatment protocols have pushed the cure rate to near 90% 1
• The 5-year event-free survival rates are approximately 80% 3
• This high cure rate is achieved through:
  • More precise risk stratification
  • Personalized chemotherapy based on leukemic cell characteristics
  • Improved supportive care
  • Host pharmacokinetics and pharmacogenetics 1

Relapse Rates and Management

• Despite high cure rates, approximately 15-20% of children with ALL experience relapse
• For patients with relapsed ALL:
  • Second complete remission (CR2) rates range from 68-72% with bortezomib-containing regimens 5
  • 5-year progression-free survival after relapse is approximately 56-72%, depending on minimal residual disease (MRD) status 5
  • Patients with MRD-positive second CR should receive additional 1-2 courses of therapy to achieve MRD-negative status prior to allogeneic hematopoietic cell transplantation (HCT) 5

Acute Myeloid Leukemia (AML)

Cure Rates

• AML represents approximately 20% of childhood leukemias 4
• Cure rates for pediatric AML are lower than ALL:
  • Approximately 40-50% 2
  • Some more recent studies report cure rates approaching 60% 3
• Treatment requires intensive anthracycline- and cytarabine-based therapy using at least 4-5 courses 5

Relapse Rates and Management

• Relapse rates in pediatric AML are higher than ALL, occurring in approximately 30-40% of cases
• For relapsed AML:
  • Second CR rates with reinduction chemotherapy range from 59-69% 5
  • Overall survival after relapse is approximately 38% 5
  • Allogeneic hematopoietic stem cell transplantation (HSCT) is recommended for all children who achieve second CR 5

Factors Affecting Cure and Relapse Rates

Cytogenetic Subtypes

• Favorable cytogenetic subtypes in ALL:
  • TEL-AML1 fusion gene (22% of pediatric cases)
  • Hyperdiploidy (>50 chromosomes) (25% of pediatric cases) 5
• Poor prognosis cytogenetic subtypes:
  • BCR-ABL fusion gene (Ph-positive ALL) (3% of pediatric cases) 5

Age Considerations

• Adolescent and young adult (AYA) patients have suboptimal cure rates (60-70% 5-7 year event-free survival) compared to younger children 5
• AYA patients have:
  • Lower frequency of favorable cytogenetic subtypes
  • Higher incidence of Ph-positive ALL 5

Minimal Residual Disease (MRD)

• MRD status is a critical prognostic factor
• MRD assessment should be performed upon completion of initial induction therapy 5
• MRD negativity is defined as <1 × 10^-4 (<0.01%) 5
• Persistent MRD positivity indicates higher risk of relapse 5

Recent Advances and Future Directions

• Novel targeted therapies are improving outcomes:

  • Blinatumomab (bispecific anti-CD3/CD19 monoclonal antibody) for relapsed B-cell ALL 5
  • Gemtuzumab ozogamicin (GO) for CD33-positive AML 5
  • Tisagenlecleucel (CAR T-cell therapy) with 3-year relapse-free survival of 52% in relapsed/refractory ALL 5

• Future improvements in cure rates are expected from:

  • Discovery of additional recurrent molecular lesions
  • Development of novel targeted treatments through high-throughput genomics
  • Innovative drug-screening systems 1
  • More precise risk-group stratification allowing more tailored treatment 6

The dramatic improvement in childhood leukemia outcomes represents one of the most remarkable successes in modern medicine, transforming what was once a universally fatal disease into one that is now largely curable.