Worldwide, Acute Lymphoblastic Leukemia (ALL) is one of the most common childhood malignancies. Approximately 75% of childhood leukemias are ALL; B Cell ALL is more common and more favorable prognostically than T Cell ALL. Overall, the long-term survival rate (survival past 5 years after diagnosis) for childhood ALL is very high, approximately 80-90%.
Favorable risk factors include:
- age <10 years old
- white blood cell count (WBC) less than 50 x 109 /L
- female gender
- B-ALL
- t(12;21) with ETV6-RUNX1 gene fusion
- high hyperdiploidy
- rapid time to complete remission after treatment
Poor risk factors include:
- age >16 years
- white blood cell count (WBC) greater than 50 x 109 /L
- male gender
- T-ALL
- hypodiploidy
- Philadelphia chromosome t(9;22)
- intrachromosomal amplification of chromosome 21
These are just a few examples. The complete diagnosis and treatment for ALL are so complex that clinicians must consider a vast array of biomarkers and other factors.