Contributions
Abstract: PB1616
Type: Publication Only
Background
Aims
Methods
Results
qPCR results showed that most of the 9p21 losses corresponded to homozygous deletions in both genes (36%, 19/53), while heterozygosis deletions corresponded to 5.7% (3/53) and different CNA status between CDKN2A and B to 28% (15/53) of the samples. Globally alterations in CDKN2A/B locus were observed in 70% (37/53) of patients. Results obtained by the array corroborate the findings obtained by qPCR. The resolution of the array allowed us to distinguish between homozygosis in CDKN2A and heterozygosis on CDKN2B. The FISH analysis corroborated the homozygous deletion in the CDKN2A/B locus in all the cases analyzed. With that, we ask for clinical implications of CDKN2A/B CNA status in 49 cases with adequate follow-up. Median age (range) was 34 (16-68) years, 76% males, median WBC count 34 (0.6-431.0) x109/L. Immunophenotype: pro-T+pre-T (n=21), cortical T (n=21), mature T (n=7). CR was achieved in 92% (45/49) and MRD levels <0.1% at the end of induction were attained in 81% of patients. A trend for better OS was observed for patients with heterozygous or homozygous deletion of CDKN2B (61% [40%>82%]) vs. non deleted patients (25% [0%>54%],(p=0.084), whereas no clinical impact was observed for the CNA status in the CDKN2A gene. No influence of CDKN2A or CDKN2B CNA status on CIR was observed. By multivariate analysis only the MRD level at the end of induction influenced on OS (p=0.028, HR=5.58 [1.21 ; 25.79]) and on CIR (p=0.07, HR= 3.67 [0.90-15.63]).
Conclusion
Session topic: 1. Acute lymphoblastic leukemia - Biology
Keyword(s): adult, T-ALL, prognosis, Gene deletion
Abstract: PB1616
Type: Publication Only
Background
Aims
Methods
Results
qPCR results showed that most of the 9p21 losses corresponded to homozygous deletions in both genes (36%, 19/53), while heterozygosis deletions corresponded to 5.7% (3/53) and different CNA status between CDKN2A and B to 28% (15/53) of the samples. Globally alterations in CDKN2A/B locus were observed in 70% (37/53) of patients. Results obtained by the array corroborate the findings obtained by qPCR. The resolution of the array allowed us to distinguish between homozygosis in CDKN2A and heterozygosis on CDKN2B. The FISH analysis corroborated the homozygous deletion in the CDKN2A/B locus in all the cases analyzed. With that, we ask for clinical implications of CDKN2A/B CNA status in 49 cases with adequate follow-up. Median age (range) was 34 (16-68) years, 76% males, median WBC count 34 (0.6-431.0) x109/L. Immunophenotype: pro-T+pre-T (n=21), cortical T (n=21), mature T (n=7). CR was achieved in 92% (45/49) and MRD levels <0.1% at the end of induction were attained in 81% of patients. A trend for better OS was observed for patients with heterozygous or homozygous deletion of CDKN2B (61% [40%>82%]) vs. non deleted patients (25% [0%>54%],(p=0.084), whereas no clinical impact was observed for the CNA status in the CDKN2A gene. No influence of CDKN2A or CDKN2B CNA status on CIR was observed. By multivariate analysis only the MRD level at the end of induction influenced on OS (p=0.028, HR=5.58 [1.21 ; 25.79]) and on CIR (p=0.07, HR= 3.67 [0.90-15.63]).
Conclusion
Session topic: 1. Acute lymphoblastic leukemia - Biology
Keyword(s): adult, T-ALL, prognosis, Gene deletion