Dominique Morel

CD5 expression identifies a subset of splenic marginal zone lymphomas with higher lymphocytosis: a clinico-pathological, cytogenetic and molecular study of 24 cases

Background Classically, splenic marginal zone B-cell lymphoma is characterized by the absence of CD5 expression. Cases of apparent splenic marginal zone B-cell lymphoma showing CD5 expression, as diagnosed by blood studies, have been described; however, in the absence of histological evidence, the correct diagnosis of these cases is controversial because of possible confusion with other CD5-positive small B-cell neoplasms. Design and Methods We report a series of 24 CD5-positive, t(11;14)-negative cases of splenic marginal zone B-cell lymphoma diagnosed by flow cytometry studies of blood and histologically proven on spleen sections. Clinical data as well as morphological, immunological, cytogenetic and molecular characteristics were assessed to evaluate the similarities and differences of these cases with those of classical CD5-negative splenic marginal zone B-cell lymphoma. Results The CD5 expression detected in blood by flow cytometry was confirmed in most cases by immunohistochemistry on spleen sections. In general, cases of CD5-positive and CD5-negative splenic marginal zone B-cell lymphoma did not appear different and, in particular, they showed similar karyotypic changes such as 7q deletion, trisomy 3, trisomy 18 and biased IGHV usage (i.e. VH1-2). The main differences were a higher lymphocyte count at diagnosis (8.15×109/L versus 3.90×109/L; P=0.005) and more frequent diffuse bone marrow infiltration (34% versus 8%; P=0.03) in the CD5-positive group. A tendency to a more mutated IGHV status in the CD5 positive cases was observed (80% versus 54.5%; (P=0.11). No significant differences in outcome were found in relation to CD5 expression. Conclusions This study confirms the existence of cases of CD5-positive splenic marginal zone B-cell lymphoma and shows that these cases are closely related to classical splenic marginal zone lymphoma. Whether or not CD5-positive splenic marginal zone B-cell lymphoma constitutes a true subset obviously requires the study of more cases.

Distribution of the cytogenetic abnormality ˛i(3)(q10) in persistent polyclonal B-cell lymphocytosis: a FICTION study in three cases

Persistent polyclonal B‐cell lymphocytosis (PPBL) is a rare entity characterized by a moderate but sustained lymphocytosis where some binucleated or bilobulated circulating forms constitute, even if they are not entirely specific, the cytological hallmark of the disease. An additional chromosome long arm i(3)(q10) has recently been reported as a recurrent cytogenetic aberration, contrasting with a usual polyclonal immunoglobulin expression. To determine more precisely the distribution of the chromosomal abnormality within the peripheral lymphocyte population and study the relationship between the +i(3)(q10) and the bilobulated character, we investigated three new cases of PPBL displaying the cytogenetic abnormality on the karyotype, using a technique of simultaneous fluorescence immunophenotyping and interphase cytogenetics (FICTION). We demonstrated that the +i(3)(q10) was restricted to the B lymphocytes, independently of the κ or λ light chain isotype and was present in both bilobulated and non‐bilobulated cells. Therefore it is likely that the cytogenetic abnormality occurs at an early stage of lymphocyte differentiation in a precursor cell already committed to the B‐cell lineage, before any rearrangement of immunoglobulin genes has taken place.

Physicochemical characterization of covalently bonded alkyl monolayers on silica surfaces

Abstract The physicochemical properties of silica surfaces covalently bonded with alkyl monolayers, in a chain length range from C6 to C22, are investigated by using chromatographic, ellipsometric and capacitance measurements. A compact structure is found with an interchain distance of about 0.67 nm; the experimental thickness is very close to the theoretical chain length value. The hydrophobic character of such chemically modified silica surfaces increases with the chain length.

Relevance of a scoring system including CD11c expression in the identification of splenic diffuse red pulp small B-cell lymphoma (SRPL)

‘Splenic red pulp lymphoma with numerous basophilic villous lymphocytes’ (SRPL), recently described, is characterized by clinical, morphologic, immunologic, cytogenetic and molecular features distinct from SMZL/SLVL and HCL. In particular, the intensity of CD11c staining (expressed as fluorescence intensity ‐RFI‐) in SRPL is significantly different from the RFI in SMZL/SLVL and HCL. Moreover the use of a scoring system based on the expression of CD11c, CD22, CD76, CD38 and CD27 appears to improve the differential diagnosis between SRPL and SMZL/SLVL and emphasizes that SRPL is an entity closed to but distinct from SMZL/SLVL. Copyright

In non-follicular lymphoproliferative disorders, IGH/BCL2-fusion is not restricted to chronic lymphocytic leukaemia.

The translocation t(14;18) and its t(2;18) and t(18,22) variants, which involve the BCL2 genetic hallmark for follicular lymphoma (FL), have been reported in several cases of chronic B‐cell lymphoproliferative disease (CLPD) and frequently in chronic lymphocytic leukaemia (CLL). We describe here the clinical, morphological, immunological, cytogenetic and molecular findings from 37 cases of t(14;18)‐positive CLPD, identified from our series of non‐FL B‐cell neoplasms (n = 993) that were routinely analysed in peripheral blood by conventional cytogenetics analyses. The FL diagnosis was excluded by morphology and immunology (the samples were CD10 negative in all cases). The BCL2 translocations were observed in 22 CLL cases, including 7 monoclonal B‐cell lymphocytosis (MBL) cases re‐classified according to the new International Workshop on CLL criteria, six small lymphocytic lymphoma (SLL) cases, 1 splenic marginal zone lymphoma (SMZL) case and eight cases of unclassifiable CLPD with overlapping CLL/MZL features. In the CLL cases, the IGH/BCL2 fusion was remarkably associated with trisomy 12 (13/22) and mutated IGHV status (20/21) and did not affect the outcome. Moreover, most of these CLLs harboured a low mutation load of BCL6 gene and unmutated FAS (CD95) loci, which points to a post–germinal‐centre cellular origin.

Quantitative study of the hydroxylation and of the chemical grafting of oxidized porous silicon

Abstract A porous silica layer was obtained by anodic dissolution of silicon and thermal oxidation. The initial porous structure of silicon is preserved after well defined oxidation treatments. The silica layer was hydrated and chemically modified by grafting bromohexyl silane. The adaptation of different analytical methods allows the determination of the silanol and the graft densities. The experimental conditions for obtaining the highest densities were defined. These results will be applied to the preparation of ion sensitive membranes for ISFET.

Alarms and Parameters Generated by Hematology Analyzer: New Tools to Predict and Quantify Circulating Sezary Cells

The rigorous cytological review by manual or automatic microscopic analysis is critical in the detection of circulating neoplastic cells, since their morphology as well as their count contributes to the diagnosis and prognosis of many diseases. However, the cytological analysis is not always obvious and requires trained and competent cytologist. In this context, the alarms and/or parameters generated by hematology analyzer could be particularly informative to alert the operators.

Analytical control of the preparation and the chemical grafting of Si/SiO2 heterostructures. Application to the fabrication of silicon microsensors

Abstract Three analytical methods were applied for the analysis of grafted planar heterostructures of Si/SiO2: neutron activation, GC and XPS analysis. Neutron activation analysis of bromoalkyl grafts allows the graft density to be quantified. Several parameters were studied: time and temperature of the hydration treatment, as well as temperature of the grafting process. GC allows the grafted alkyl and perfluorinated chains (C≥8) to be identified and quantified. Optimal conditions have been defined to obtain dense alkyl layers. The XPS method allows a qualitative control of the surface to be performed at each physical and chemical process but a quantitative determination of the graft density cannot be done because of the carbon contamination and of the instability of bromoalkyl and perfluorinated grafts under the photon beam. From these results, optimal experimental conditions have been found for the fabrication of grafted selective membranes for chemical and biochemical silicon sensors.

Unusual spheroids in cerebrospinal fluid

We report on a case of AIDS-related plasmablastic lymphoma with clinical suspicion of meningeal relapse in a 43-year-old male patient. After six cycles of R-CHOP and two cycles of cytarabine–methotrexate, the patient progressed 6 months later with left third nerve palsy and bilateral axillary lymph nodes. HIV infection was under efficient antiretroviral treatment. Magnetic resonance imaging detected a tissue infiltration of the left superior orbital fissure with extension in the cavernous sinus and infiltration of the right and left muscle. In the cerebrospinal fluid (CSF), cell count was normal (leukocytes < 2 ⁄ lL), protein concentration was 0.48 g ⁄L, and glucose level was 5.31 mm. Viral PCR tests in CSF for the detection of HSV, CMV, VZV, and enteroviruses were negative. Mycobacteria PCR test and cryptococcal antigen testing as well as syphilis and Lyme borreliosis serologies were also negative. CRP and renal function were normal. Full blood count revealed a normal white cell count of 6.3 · 10 ⁄L, a hemoglobin level of 10.3 g ⁄dL, and a platelet count of 405 · 10 ⁄L. Aggressive lymphoma was treated with intrathecal injection of liposomal cytarabine, cyclophosphamide, and etoposide. When the CSF cell count during the follow-up reached an apparently abnormal threshold (50 ⁄ lL), the first concern was a possible refractory plasmablastic lymphoma. However, the examination of May–Grünwald–Giemsastained slides prepared on cytospins showed a very low cellularity with only few normal lymphoid cells. This was in discordance with the initial cell count, and we wondered whether fragile cells were destroyed during cytocentrifugation. A more careful direct examination of the CSF by varying the focus under a light microscope revealed unusual spheroid images (10–20 lm) with internal fine granular structure (Fig. 1a, b) among few red blood cells (Fig. 1d). This observation is consistent with remnants of cytarabine liposomes of the last injection. Moreover, we frequently noticed an obvious unique refractive vesicle close to the membrane of the spheroids. In few of them, we also observed half-empty spheroids, which might be due to the drug release or breakdown of the membrane lipids (Fig. 1c). Multivesicular liposomes consist of an aggregation of several polyhedral compartments providing drug encapsulation. This technology is referred to as DepoFoam (SkyePharma PLC, London, UK), and the first clinically available formulation was DepoCyt containing liposomal cytarabine. Intrathecal injection of DepoCyt results in a prolonged drug release in the CSF for approximately 14 days. The average diameter of multivesicular liposomes ranged from 10 to 30 lm as mentioned in the product monograph. Thus, because DepoCyt particles may have a similar aspect to tumor cells or leukocytes and have a delayed clearance, CSF examination should be carefully analyzed to avoid counting errors or misinterpretation. Our simple morphological description allows the discrimination of liposomal structures from cells on hemocytometer used for manual cell counting. Medical laboratory should be informed of this easily recognizable presentation in CSF and have to inquire about treatment with liposomal drugs.