21 - Treatment of adolescents and young adults with acute lymphoblastic leukemia

Summary

Introduction

Outcome for young adult patients with acute lymphoblastic leukemia (ALL) is inferior to that of children aged 10 to 14 years and particularly those aged 1 to 9 years at diagnosis. For patients 15 to 24 years of age at diagnosis, 5-year survival has increased steadily from 36.2% in the 1980s to 55.7% in the 1990s. However, there has been no improvement in outcome for patients treated between 2000 and 2005.

Adolescents with ALL are a unique group in that treatment may be provided by either medical or pediatric oncologists. Referral to an oncologist is generally based on the preference of the primary care provider: internists and family practice physicians generally refer patients to medical oncologists while pediatricians refer patients to pediatric oncologists. Adults with ALL have a worse outcome compared with children. The reasons for a worse outcome in adult patients with ALL include a lower incidence of favorable genetic subtypes (t(12;21) or hyperdiploidy), a higher incidence of t(9;22), the presence of comorbidities in older adults, and greater treatment-associated morbidity and mortality. Avascular necrosis of bone is a significant complication of therapy that occurs almost exclusively in adolescents and young adults. There is also a significantly lower salvage rate for older patients who experience a relapse compared with younger patients.