Deletion of CDKN2A/B is associated with inferior relapse free survival in pediatric B cell acute lymphoblastic leukemia

Abstract

Considering conflicting data on CDKN2A/B deletion in ALL, this study to assess its prognostic significance as an independent marker in a total of 96 pediatric B and T-ALL cases was planned. The overall frequency of CDKN2A/B deletion was 44% (n = 43) with 36% (30/83) in B-ALL and 100% (13/13) in T-ALL. CDKN2A/B deletion was significantly associated with high WBC count (p = .002) and National Cancer Institute risk (p = .01) in B-ALL. Importantly, CDKN2A/B deletion cases had poor EFS of 42% at 28 months compared to EFS of 90% in rest (p = .0004). Further, relapse free survival was only 56% for cases with CDKN2A/B deletions (n = 25), compared to 100% in control group (p = .001). Moreover, CDKN2A/B deletion was the only risk factor associated with early relapse (p = .01) compared to IKZF1 deletion (p = .73) or occurrence of BCR-ABL1 fusion transcript (p = .26). Thus our study data highlights potential prognostic role of CDKN2A/B deletions in early disease stratification in pediatric B-ALL.

Keywords:

• Acute lymphoblastic leukemia
• BCP-ALL
• MLPA
• copy number abnormality
• CDKN2A/B
• minimal residual disease

Acknowledgments

The study was supported by research grant from Council of Scientific and Industrial Research (CSIR), New Delhi, India [grant no. 27(312)/15, 2015–2018] and Institute’s (PGIMER, Chandigarh) special research grant for DM/MD thesis completion. The authors would like to acknowledge and thank CSIR and PGIMER for sponsoring our research proposal.

Potential conflict of interest

Disclosure forms provided by the authors are available with the full text of this article online at https://doi.org/10.1080/10428194.2018.1482542.