Use

Loss of the CDKN2A/B gene (also called p16 or pINK4A) at 9p21 is frequently observed in acute lymphocytic leukemia (30-40% of cases) and requires a method more sensitive than cytogenetics (such as FISH) for reliable detection. CDKN2A/B gene deletion is associated with an adverse prognosis in pediatric, adolescent, and adult patients with B-cell ALL (B-cell precursor or BCP-ALL) due to increased risk for relapse, poor response to therapy, lower overall survival, and/or higher incidence of concurrent deletion of other genes. Reports vary whether the impact of heterozygous deletions is as severe as homozygous deletions.