Probes: CDKN2A (p16) (9p21) | Centromere 9
Disease(s): Acute Lymphoblastic Leukemia (ALL)
Loss of the CDKN2A 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 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.
1. Braun M, Pastorczak A, Fender W, et al. Biallelic loss of CDKN2A is associated with poor response to treatment in pediatric acute lymphoblastic leukemia. Leuk Lymphoma. 2017;58:1162-1171.
2. Messina M, Chiaretti S, Fedullo AL, et al. Clinical significance of recurrent copy number aberrations in B-lineage acute lymphoblasticleukaemia without recurrent fusion genes across age cohorts. Brit J Haematol. 2017;178(4):583-587.
3. Ribera J, Zamora L, Montesinos P, et al. Prognostic significance of copy number alterations in adolescent and adult patients with precursor B acute lymphoblastic leukemia enrolled in PETHEMA protocols. Cancer. 2015;121:3809-3817.
- Bone Marrow Aspirate: 1-2 mL sodium heparin tube. EDTA tube is acceptable.
- Peripheral Blood: 2-5 mL sodium heparin tube. EDTA tube is acceptable..
- Fresh, Unfixed Tissue: Tissue in RPMI.
- Fluids: Equal parts RPMI to specimen volume.
- Paraffin Block or Cut Slides: Not available.