The prognostic value of flow cytometry determination of CD38 and CD49d on leukemic cells of Argentinian CLL patients.

CORDINI, GREGORIO; ELÍAS ESTEBAN ENRIQUE; ANA COLADO; MARICEF VERGARA RUBIO; MORANDE, PABLO E; ALEXIA VEREERTBRUGGHEN; CARMEN STANGANELLI; SLAVUTSKY IRMA; FERNÁNDEZ GRECCO HORACIO; ROSARIO CUSTIDIANO; JULIO CÉSAR SÁNCHEZ AVALOS; ÁNGELES VICENTE; GONZALO MARTÍN GARATE; BEZARES FERNANDO; BORGE MERCEDES; GIORDANO MIRTA; GAMBERALE ROMINA

Edimburgo

Workshop; XVIII International Workshop on Chronic Lymphocytic Leukaemia; 2019

iwCLL Consortium

CLL shows a highly variable clinical course, which can be predictedby several biologic markers, includingthe mutational status of immunoglobulin heavyvariable (IGHV) gene, genomic abnormalities,and expression of CD38 and CD49d.The aim of this study was to determine whether combined flow cytometry determination of CD38 and CD49d can be used to predict time to first treatment(TTFT) in our cohort of CLL patients. The study includes peripheral blood samples from 159 patients affected by typical B-CLL. The median age at diagnosis was 73 years with a male to female ratio of 1.65. The median follow-up of our patients was 10.3 years; 60 out of 159 required treatment (37.7%) with a median TTFT of 8.3 years(95% CI 5.7-11.8). The distribution of clinical stages at diagnosis according to Rai?s criteriawas: 36.8%, stage 0; 26.5%, stage I; 14.7%, stage II; 5.9%, stage III; 16.2%, stage IV. Fluorescence in situ hybridization (FISH) testing was available for 69 patients: del13q14 26.9%, del11q22 7.2%, del17p13 15.9% and trisomy 12 15.2%. The IGHV mutational status, available for 82 out of 159 cases showed 63.4% of mutated-and 36.6% of unmutated-IGHV gene configuration. The expression of CD38 and CD49d on CD19+ cells was evaluatedin our laboratory by three-colorimmunofluorescence, as previously described (1), employing PE-conjugated anti-CD38 or anti-CD49d monoclonal antibodies (mAbs) withPerCP-conjugated anti-CD19 mAbs.Patients with ≥7% of CD19+ cellsexpressing CD38 were considered CD38+(2) and patients with ≥30% of CD19+ cellsexpressing CD49d were considered CD49d+(3).Figure 1A shows the percentage of CD19+ cells expressing CD38 and CD49d for each of the 159 CLLpatients. We found that 46 patients (28.9%) were CD38+ and CD49d+, while 67 patients were negative for both markers (42.2%).The remaining samples were discordant for the expression of CD38 and CD49d:28 patients (17.6%) were CD38+CD49d- and 18 patients (11.3%) were CD38-CD49d+. As previously described(4), the association between the two antigens washighly significant (p