Polyclonal B-cell lymphocytosis with binucleated lymphocytes (PPBL)

Persistent polyclonal B-cell lymphocytosis (PPBL) is a rare and recently described entity. The review of the literature show PPBL is diagnosed predominantly but not exclusively in women, usually smokers. PPBL is recognized by a moderate, chronic and absolute lymphocytosis (>4 × 109/l) in the peripheral blood. In 10% of cases without lymphocytosis, the PPBL diagnosis has to be suggested by peripheral blood examination showing in all cases atypical binucleated lymphocytes. A polyclonal serum IgM is also associated and HLA-DR7 expression is present in most cases. Contrary to B-cell chronic lymphoproliferative disorders (B-CLPD), peripheral B cells are polyclonal with kappa and lambda light-chain expression and no clonal rearrangement of immunoglobulin heavy chain genes is usually demonstrated. The detection of an extra isochromosome for the long arm of chromosome 3 +i(3)(q10) has to be considered as a specific marker of PPBL. We performed conventional cytogenetic analysis (CCA) in 111 patients with typical PPBL we followed-up more than 4 years. +i(3q) was detected in 34% (33/98), PCC in 8% (8/98) and both abnormalities in 31% (30/98). CCA showed neither +i(3q) nor PCC in 28% (27/98). Fluorescence in situ hybridization (FISH) was also performed in 84 cases and +i(3q) was detected in 71% (60/84). When combining both procedures in 84 patients, +i(3q) was detected in 17 patients with negative CCA and was confirmed in 43 patients with positive CCA. CCA and FISH were both negative in 24 cases. Whether patients with PPBL are at increased risk of hematological malignancy remains unclear. After a median follow-up of 4.4 years, most PPBL patients presented a stable clinical and biological course. Six patients died from pulmonary cancer, myocardial infarction, cerebral aneurysm rupture or diffuse large B-cell lymphoma. Two patients had IgM monoclonal gammopathy of undetermined significance (MGUS) at the time of PPBL diagnosis and two other patients developed IgM MGUS respectively 12 and 22 years after PPBL diagnosis. A malignant non Hodgkin's lymphoma (NHL) appeared in 3 additional patients: two patients presented diffuse large B cell lymphoma and 1 patient a splenic marginal zone lymphoma. In conclusion, the possibility of PPBL to evolve toward a clonal proliferation, malignant lymphoma or secondary solid cancer lead us to consider PPBL not as a benign pathology. We recommend a careful and continued clinical and biological long-term follow-up in all PPBL patients

Recommendations of the SFH (French Society of Haematology) for the diagnosis, treatment and follow-up of hairy cell leukaemia

International audienceHairy cell leukaemia (HCL) is a rare haematological malignancy, with approximately 175 new incident cases in France. Diagnosis is based on a careful examination of the blood smear and immunophenotyping of the tumour cells, with a panel of four markers being used specifically to screen for hairy cells (CD11c, CD25, CD103 and CD123). In 2011, the V600E mutation of the BRAF gene in exon 15 was identified in HCL; being present in HCL, it is absent in the variant form of HCL (HCL-v) and in splenic red pulp lymphoma (SRPL), two entities related to HCL. The management of patients with HCL has changed in recent years. A poorer response to purine nucleoside analogues (PNAs) is observed in patients with more marked leukocytosis, bulky splenomegaly, an unmutated immunoglobulin variable heavy chain (IgVH) gene profile, use of VH4-34 or with TP53 mutations. We present the recommendations of a group of 11 experts belonging to a number of French hospitals. This group met in November 2013 to examine the criteria for managing patients with HCL. The ideas and proposals of the group are based on a critical analysis of the recommendations already published in the literature and on an analysis of the practices of clinical haematology departments with experience in managing these patients. The first-line treatment uses purine analogues: cladribine or pentostatin. The role of BRAF inhibitors, whether or not combined with MEK inhibitors, is discussed. The panel of French experts proposed recommendations to manage patients with HCL, which can be used in a daily practice

Long-term follow-up of 111 patients with persistent polyclonal B-cell lymphocytosis with binucleated lymphocytes.

International audienceInitially described in 1982, the persistent polyclonal B-cell lymphocytosis (PPBL) is characterized by a chronic, stable, persistent and polyclonal lymphocytosis, the presence of binucleated lymphocytes in the peripheral blood and a polyclonal increase in serum immunoglobulin-M (IgM). In this apparently benign entity, we showed that PPBL was associated with recurrent chromosomal abnormalities and a typical cytogenetic profile including isochromosome 3q, +i(3q), premature chromosome condensation (PCC), both abnormalities in the same patient or chromosomal instability. Despite clinical and polyclonal lymphocytosis stability, the long-term follow-up is not yet well established.We analyse and report here the long-term follow-up of 111 patients with typical PPBL

Etude de la dormance tumorale dans les leucémies aiguës myéloïdes (caractérisation phénotypique et génotypique des cellules leucémiques et étude des facteurs impliqués dans la dormance tumorale)

CAEN-BU Médecine pharmacie (141182102) / SudocSudocFranceF

L'hémogramme au laboratoire (nouvelles perspectives)

L hémogramme est un examen essentiel à la prise en charge des patients dans de multiples pathologies. Les analyseurs d hématologie cellulaire permettent de réaliser de façon fiable et rapide les numérations et les formules leucocytaires. Les conditions pré-analytiques sont aussi essentielles à la qualité des résultats. Nous avons montré que les délais et températures de conservation des échantillons ont une incidence sur les résultats. Nous avons notamment observé une augmentation du volume globulaire moyen dès six heures si l échantillon est conservé à température ambiante. Malgré les performances analytiques satisfaisantes des analyseurs, l examen microscopique du frottis sanguin est indiqué pour la recherche de cellules anormales et le contrôle des formules dont le résultat est douteux. La formule manuelle est soumise à de nombreuses variations liées au faible nombre de cellules comptées mais est considérée comme la technique de référence. Dans ce contexte, des méthodes de cytométrie en flux permettant de réaliser de façon simple une formule leucocytaire se développent. Nous avons ainsi évalué les performances analytiques du système HematoFlow , qui utilise un panel de six anticorps et permet d identifier 17 populations leucocytaires. Les paramètres de corrélation avec la formule manuelle sont satisfaisants. Nous avons observé des discordances liées à des problèmes d autogating ou d expression des marqueurs par les cellules. En cas d hyperlymphocytose, la sensibilité de détection des pathologies lymphoïdes B est supérieure à celle de la méthode microscopique. Ce système peut ainsi s intégrer dans la démarche diagnostique en complément du frottis sanguin.CAEN-BU Médecine pharmacie (141182102) / SudocSudocFranceF

Leucémie à tricholeucocytes Correspondance : Points essentiels

International audienc