Table 2.
Novel key genomic alteration associated with prognosis in adult ALL
| Gene alteration | Frequency | Comments |
|---|---|---|
| IKZF1 deletions and sequence mutations |
15% of pediatric B-ALL cases; 70% of BCR-ABL1 + lymphoid leukemia, and 30% of high-risk BCR-ABL1-like B-ALL |
IKZF1 alterations are associated with poor outcome in both BCR-ABL1–positive and negative ALL cases, and triple the risk of treatment failure. IKZF1 status is an independent risk factor at a multivariable analysis of established prognostic factors. |
| CRLF2 rearrangement (as IGH@-CRLF2 or P2RY8-CRLF2) |
Up to 16% of pediatric and adult B-ALL; >50% Down syndrome (DS) ALL |
Concomitant JAK1/2 mutations in >50% of cases; associated with IKZF1 alteration and poor outcome, particularly in non-DS-ALL. |
| JAK1/2 mutations |
Up to 10% of high-risk BCR ABL1-like B-ALL; 18–35% of DS ALL |
Almost all cases of B-ALL with JAK1/2 mutations harbor concomitant CRLF2 rearrangement, associated with poor outcome; may be responsive to JAK inhibitors. |
| CREBBP deletions and sequence mutations |
19% of relapsed B-ALL |
Associated with glucocorticoid resistance; Resulted in impaired acetylation of histone targets; histone deacetylase inhibitors may be useful. |
| CDKN2A/B deletions |
~30% of B-ALL; 47% of relapsed BCR-ABL1-ALL; |
Associated with poor outcome in terms of overall survival, and incidence of relapse in adult BCR-ABL1-positive ALL; controversial prognosis in other B-ALL subtypes. |
| TP53 deletions and sequence mutations |
Up to 12% of B-ALL; |
Enriched at relapse and associated with non-response to chemotherapy and poor event-free survival and overall survival. |
| PHF6 deletions and sequence mutations |
38% of adult T-ALL cases |
Associated with reduced overall survival. |
| PTEN deletions and sequence mutations |
6–8% of T-ALL |
Associated with poor response to chemotherapy and resistance to pharmacological inhibition of NOTCH1 |
| N/K-RASmutations |
10% of adult T-ALL |
N/K-RASmutations demonstrated trends to a worse outcome. |
| NOTCH1 mutations |
~50% of T-ALL |
Associated with favorable outcome |
| FBXW7 mutations |
12-24% of adult T-ALL |
Associated with favorable prognosis due to enhanced glucocorticoid receptor α levels and steroid sensitivity |
| NT5C2 mutations | 19% of relapse T cell ALL and 3% of relapse B-precursor ALL | NT5C2 mutant proteins increase nucleotidase activity in vitro and drive resistance to treatment with nucleoside analog therapies |