Genomic alterations in chronic lymphocytic leukemia and their correlation with clinico-hematological parameters and disease progression

Chronic lymphocytic leukemia (CLL) is a heterogeneous disease, which is attributed to differences in the genetic characteristics of the leukemic clone. We studied the genomic profile of 52 treatment-naïve CLL patients. Genetic analysis was performed by multiplex ligation-dependent probe amplification (MLPA) using the SALSA P038 Probemix (MRC Holland, Amsterdam), which contains probes for 2p ( ), 6q, 8p ( ), 8q ( ), 9p21 ( ), 10q ( ), 11q ( ), chromosome 12, 13q14 ( ), 14q, 17p ( ) and chromosome 19, and for NOTCH1 7541-7542delCT, SF3B1 K700E, and MYD88 L265P mutations. The median age was 65 years (male:female=2:1). The median hemoglobin, total leukocyte, and platelet counts were 12.4 g/dL, 57.7×10 /L, and 176.5×10 /L, respectively. At least one genetic abnormality was observed in 34 (65%) patients. The most common abnormality was del(13q14) (deleted and / genes), which was observed in 22 (42%) cases, followed by trisomy 12 [7 (13%) cases]. Del(11q) (deleted ) and del(17p) (deleted ) were present in 5 (10%) and 2 (4%) cases, respectively. 19p13.2 ( ) amplification and mutation were found in one case each. Genetic abnormalities are commonly (65%) observed in CLL patients. Del(13q), which is associated with and / gene deletion, was the most common. Compared with other abnormalities, del(11q) and del(17p) patients presented with cytopenia and higher Binet stage, while those with del(13q14) had a longer time to first treatment.