ALBERT

Description: Introduction/ Background : Chronic lymphocytic leukemia (CLL) is a heterogeneous disease which can present as an aggressive and life threatening leukemia or as an indolent form that will not require treatment for decades. This heterogeneity has important consequences which will impact on clinical approaches, treatment strategies, and survival times from diagnosis. Prognostic markers such as expression of specific proteins in or on CLL cells (ie, CD38, 70-kD ζ-associated protein or CD49d), cytogenetic abnormalities (del 13q, del 11q, del 17p and trisomy 12) quantified by FISH and immunoglobulin heavy chain (IgVH) gene mutation have all been very useful. Futhermore, patients with early-stage disease, with biologically aggressive disease and shorter survival times can be distiguished. However, these prognostic tests are expensive and require considerable technical expertise and equipment and thus are not available to many patients with CLL living in developing countries. Therefore less expensive prognostic markers are needed. In this study, we evaluated the prognostic significance of smudge cells percentage on a blood smear in CLL patients. Patients and Methods : In this prospective study, 42 untreated patients with CLL have participated after signing a consent form. Patients were seen at our center between July 2011 and May 2015. Patients were diagnosed on the basis of an absolute lymphocyte count greater than 5.109/L and a demonstration of monoclonality using flow cytometry (panel comprising CD19, CD5, CD22, CD23, FMC7, and surface Ig). Staging was done according to the Binet staging system. CD38 surface expression was determined by flow cytometry in all patients. The cytogenetic abnormalities : del 13q, del 11q, del 17p and trisomy 12, were performed by FISH and available for 25 patients.Smudge cells were defined as broken cells with no intact cytoplasm and a disrupted nuclear membrane (Figure 1). The smudge cell percentage is estimated by counting 200 lymphocytes and/or smudge cells; the smudge cell number is then divided by total number of cells counted (smudge cells + intact lymphocytes) and multiplied by 100. Each slide was evaluated by 2 hematologists and the blood smears were prepared using a manual wedge method. Categorical variables were analyzed using the χ2 test or Fisher exact test (p

Description: The incidence of CLL in Africa is not known for several reasons, among them the difficulty to access the diagnosis since there is only clinical features and cytology which are available in several countries in francophone Africa, especially in Senegal. The WHO criteria which have been published since 2001 from the first revised WHO classification of tumours of haematopoitic and lymphoid tissues cannot be applied since there is no facility for immunophenotyping and cytogenetic. Moreover, no research in place can be set up without any precise diagnosis. In this study, we have developed the flow cytometry technique in the laboratory of Immunology in CHU Le Dantec in Dakar to obtain the immunophenotype looking at the expression of Kappa/lambda light chains, CD19, CD22, CD20, FMC7, CD5, CD10, CD23, CD38. Peripheral blood smears were fixed according to the technique for FISH to detect the following cytogenetic abnormalities: trisomy12, deletion 13q14, deletion 11q22-23, deletion 17p. RNA to test by qRT-PCR the expression of microRNA mir15a, mir16-1, mir181a, mir181b, and mir 34a and 34b was obtained from peripheral blood lymphocytes. Twelve cases of CCL aged ranging from 50 to 80 year old were characterized at clinical level according to the Binet’s system: 1 stage A, 5 stage B, 6 stages C. In most of cases (9 cases) hyperlymphocytosis of small lymphocytes with clumped chromatin and scanty cytoplasm was very high (122.000 to 336 000/mm3). The “Matutes” score obtained by immunophenotyping was 5 or 4 for 11 patients in favor of typical CLL. The expression of CD38 which is a marker of unfavorable prognosis is positive in 9 patients. Nine patients had cytogenetic abnormalities: 3 trisomy 12, 6 del 13q14, 2 del 11q22-23, 1 del17p. Four patients had two simultaneous cytogenetic abnormalities (tri 12, tri 13 ; del13q14, del11q22-23 ; del13q24, del17p ; del13q24, tri12). The analysis of mi-RNA showed high expression of mir15a and mir 16-1 and low value of mir181a and mir 181b which were described in aggressive CLL ; however the expression of mir 34a and mir34b was also high. This study shows the aggressiveness of CLL in Senegal, probably due to the delay of the diagnosis. We have also demonstrated the possibility to set up immunophenotype and the possibility of a precise diagnosis of lymphoproliferative disorder in place, in western Africa and the series will be extended. Moreover we have also demonstrated the possibility to construct translational research project from samples characterized in the University Hospital in Dakar gathering the cases from different sanitary structures in the country. Such experiment would be a model for epidemiologic, clinico-biologic and translational research studies in order to set up in the country the capacity building for diagnosis and research. Disclosures: No relevant conflicts of interest to declare.

Description: Introduction : Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western populations, being rarer in Asian and African people. It has been suggested that patients with CLL from Africa might have a more aggressive disease compared with Causasien patients. In this study, we aimed to identify genetic factors that may account for this difference Methods: We collected peripheral blood mononuclear cells (PBMCs) from a total of 75 patients with CLL, 25 from Senegal (Africa), and 50 from Siena. Since it is well known that there are differences in germline IGH repertoires between different populations, we also collected PBMCs from five healthy Senegalese individuals as control. We analyzed immunoglobulin heavy chain (IGH) genes mutational status by performing next-generation sequencing in these 2 groups of patients. Results: We found that Senegalese patients more frequently had adverse prognostic factors and an unmutated profile. Furthermore, we documented that IGHV1 (IGHV1-69), IGHD3, and IGHJ6 were significantly more frequent in Senegalese patients, whereas IGHV3-30 was common and limited to the Italian cohort. Stereotyped receptors commonly detected in the white population were not recorded in our Senegalese series. Conclusion: The different IGH repertoire we observed in the Senegalese cohort may reflect the diverse genetic and microenvironmental (ie, polymicrobial stimulation) background. Disclosures Gozzetti: Takeda: Honoraria; Amgen: Honoraria; Janssen: Honoraria, Research Funding.