Why Do Children with Acute Lymphoblastic Leukemia Fare Better Than Adults?

Abstract

It is a new and exciting time for acute lymphoblastic leukemia (ALL). While nearly 50 years ago, only one in nine children with ALL survived with chemotherapy, nowadays nearly 90% of children have a chance of long-term survival. Adults with ALL, as well as the special category of adolescents and young adult (AYA) patients, are catching up with the new developments seen in children, but still their prognosis is much worse. A plethora of factors are regarded as responsible for the differences in treatment response, such as age, ethnicity, disease biology, treatment regimens and toxicities, drug tolerance and resistance, minimal residual disease evaluation, hematopoietic stem cell transplantation timing and socio-economic factors. Taking these factors into account, bringing pediatric-like protocols to adult patient management and incorporating new agents into frontline treatment could be the key to improve the survival rates in adults and AYA.

Keywords: acute lymphoblastic leukemia; adolescents and young adults; differences in treatment response; novel therapies; pediatric-like protocols; prognosis; survival rates.

Figure 1

The schematic mechanisms of action of novel therapies. The mechanism of action of monoclonal antibody Rituximab (antiCD20), Daratumumab (antiCD38), antibody–drug conjugate Inotuzumab ozogamicin (antiCD22), bi-specific antibody Blinatumomab (CD3 antiCD19 T cell engager) and CAR-T cells (followed by expansion and differentiation after infusion).