Clinical And Biological Features Of Patients With Chronic Lymphocytic Leukemia And Trisomy 12

ObjectiveTo establish the incidence of+12 in chronic lymphocytic leukemia(CLL) patients, and its association with the different clinical stage,IgVH gene mutation status,ZAP-70 (70-kd zeta-associated protein) and CD38.MethodsConventional cytogenetics(CC) and interphase fluorescence in situ hybridization (FISH) were used to detect chromosomal abnormalitie,s in bone marrow or peripheral blood cultures in 61 cases with CLL.Multi-PCR and sequencing techniques were used to detect the IgVH gene mutation status in 52 CLL cases.Multiparametric flow cytometry and a panel of monoclonal antibodies were used to immunophenotype 30 CLL patients with+12.ResultsA total of 10/60 patients(11.7%) had chromosomal abnormalities by CC,while 49/60 patients(80.3%) had chromosomal abnormalities by FISH,13 cases(21.30%) with+12 were detected.No association was found between the+12 incidence and clinical stage (P＞0.05).There was significant difference in the age between those with and without+12 (P＜0.05).Using multiplex PCR,somatic hypermutation status of IgVH genes were easily and rapidly analyzed.The results showed that 38(73%) patients had mutated IgVH, whereas 14 others had unmutated IgVH.In CLL with+12,6(60%) patients had mutated IgVH,whereas 4 others had unmutated IgVH.There was a significant association between +12 and IgVH mutation status(P＜0.05).No association was found between ZAP-70 and IgVH mutation status(r=0.023,P=0.876),A significant association was found between CD38 and IgVH mutation status(r=0.318,P=0.024).A significant association was found between +12 and CD38 expression(P＜0.05).No association was found between +12 and ZAP-70 expression(P＞0.05).ConclusionTrisomy 12 was one of most common chromosomal abnormalities in CLL,the application of FISH would establish more accurately the incidence of+12.A significant association was found between+12 and IgVH mutation,CD20 and CD38 expression were more frequent in+12 versus the non+12 cases.It remained to be determined whether this abnormality was associated with a worse clinical stage.