Prognostic significance of CDKN2A/B deletions in acute lymphoblastic leukaemia: a meta-analysis

Cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) genes are frequently altered in acute lymphoblastic leukaemia (ALL) patients. The aim of this meta-analysis was to comprehensively assess the prognostic value of CDKN2A/B deletions in ALL patients.

Systematic literature review was conducted in PubMed, Embase and Cochrane databases up to July 2018. Pooled hazard ratios (HRs) with 95% confidence intervals (CIs) were calculated with fixed-effects or random-effects models.

A total of thirteen studies including 2857 patients were eligible for this meta-analysis. Combined HRs suggested that CDKN2A/B deletions were poor prognostic factors for both overall survival (OS) (HR = 2.15, 95% CI 1.82-2.54) and event-free survival (EFS)/disease-free survival (DFS)/relapse-free survival (RFS) (HR = 2.16, 95% CI 1.73-2.69). The adverse impact remained significant in both adult and paediatric ALL patients, and also in subgroups by ethnicity, ALL type, detection method of CDKN2A/B deletions, statistical method and endpoint.

Our findings suggested that CDKN2A/B deletions were associated with poor prognosis independently in both adult and childhood ALL patients. Inclusion of CDKN2A/B status may further improve the risk stratification of ALL patients. Key Messages Although numerous studies have explored the prognostic significance of cyclin-dependent kinase inhibitor 2A/B (CDKN2A/B) deletions in acute lymphoblastic leukaemia (ALL) patients, the results remain conflicting. In this meta-analysis, we found that CDKN2A/B deletions were independent poor prognostic markers for both adult and paediatric ALL patients. Our findings justify the inclusion of CDKN2A/B status in the risk stratification of ALL patients.