Genome-Wide Single-Nucleotide Polymorphism Array Analysis Improves Prognostication of Acute Lymphoblastic...

Area of Science:

• Hematology
• Oncology
• Genetics

Background:

• Chromosomal abnormalities are crucial for acute lymphoblastic leukemia (ALL) risk stratification.
• Traditional cytogenetic analysis misses clinically relevant abnormalities in a significant portion of pediatric (30%) and adult (50%) ALL patients.

Purpose of the Study:

• To evaluate the utility of integrating whole-genome single-nucleotide polymorphism (SNP) array analysis with conventional cytogenetics and fluorescence in situ hybridization (FISH) for detecting clinically significant aberrations in ALL.
• To improve the diagnostic yield for ALL risk stratification.

Main Methods:

• Integration of cytogenetic, FISH, and whole-genome SNP array data from 60 consecutive ALL cases.
• Analysis of B-cell ALL (B-ALL) and T-cell ALL (T-ALL) for recurring and additional chromosomal aberrations.

Main Results:

• Conventional methods detected abnormalities in 33 B-ALL cases.
• SNP array analysis identified additional clinically significant aberrations in 21 B-ALL and 2 T-ALL cases, including IKZF1 deletion and novel fusion genes.
• The combined approach increased the detection rate of clinically significant abnormalities from 56% to 75%.

Conclusions:

• Whole-genome SNP array analysis detects cytogenetically cryptic aberrations with prognostic and therapeutic implications.
• Routine application of SNP array analysis at ALL diagnosis enhances detection of clinically significant abnormalities, improving risk stratification.