Multiprobe FISH Panels for Chromosome Rearrangements in Patients with Adult Acute Lymphoblastic Leukemia.

Abstract 4122

For acute Lymphoblastic Leukemia(ALL), several cytogenetic aberrations have been shown to play a crucial role in clinical Prognosis and also are being used as targets for response to therapy. This has led to Cytogenetics, and more recently Fluorescence In Situ ybridization(FISH), to be a tool for the detection of ALL treatment trials. Conventional cytogenetic(CC) analysis is a technically demanding and time-consuming process that is hindered by the limited availability of informative metaphase cells. Thus, interphase FISH is often used to complement CC,rule out submicroscopic rearrangements, and evaluate specimens with poor morphology or no growth in culture.

The Chromoprobe Multiprobe ALL panel (Cytocell Technologies,Cambridge, UK) has been designed to detect rearrangements that occur primarily in B-cell lineage ALL, and includ some T-lineage markers. This panel detect the rearrangements of MYC, E2A, MLL, IGH, and p16; fusions of BCR/ABL and TEL/AML1 simultaneously; enumeration of chromosomes 4, 10, and 17 Probes for the specific rearrangements can also be used to assess ploidy. In this study, we performed the multi-probe FISH assay on interphase cells to detect multiple abnormalities associated with adult ALL.At prensent, We analyzed 48 samples from ALL cases using a FISH panel,the results showed that 71% cases had 1 or more genetic abnormalities. The most frequent abnormality was BCR/ABL, followed by MLL, IGH abnormalities, MYC rearrangement, TEL/AML1 fusion, +10, p16, 8 cases had MLL with IGH abnormalities and TEL/AML1 fusion, 7 cases had BCR/ABL fusion with MYC rearrangement,3cases had MLL and p16, no fusion partner was detected in 14 cases. Meanwhile,detected this samples with CC,we found that 42% cases had chromosome abnormalities,and 16% samples without growth in culture. This reults preliminary demonstrated that ALL always with multiple karyotype abnormalities, Multiprobe FISH is an essential method to refine the cytogenetic analysis. This study is going on,further study including more samples was necessary.