Methotrexate (MTX) is an immunosuppressor that is widely used to treat autoimmune diseases, including rheumatoid arthritis (RA). However, it can have serious adverse effects including a lymphoma: MTX-associated lymphoproliferative disorder (MTX-LPD). Extranodal lesions are common in MTX-LPD patients. However, MTX-LPD in the central nervous system (CNS) is extremely rare with few reported cases. Here, we describe a case of primary CNS MTX-LPD in a patient with RA, with a review of the literature. A 68-year-old woman who had received MTX for her RA for more than 10 years was referred to our hospital. Head magnetic resonance imaging (MRI) showed multiple lesions with heterogeneous contrast enhancement scattered throughout both hemispheres. As immunosuppression caused by MTX was suspected, MTX was discontinued, based on a working diagnosis of MTX-LPD. We performed an open biopsy of her right temporal lesion. Histopathologic examination showed atypical CD20+ lymphoid cells, leading to a definitive diagnosis of diffuse large B-cell lymphoma (DLBCL). In situ hybridization of an Epstein-Barr virus-encoded small RNA (EBER) was positive. Sanger sequencing confirmed that both MYD88 L265 and CD79B Y196 mutations were absent. The LPD regressed after stopping MTX. Follow-up head MRI at 8 months after surgery showed no evidence of recurrence. Although primary CNS MTX-LPD is extremely rare, it should be included in the differential diagnosis when a patient receiving MTX develops CNS lesions. Diagnosis by biopsy and MTX discontinuation are required as soon as possible.

Keywords: CD79B; MTX-associated LPD; MYD88; Methotrexate; Primary central nervous system lymphoma.

Moreau score has been used to differentiate chronic lymphocytic leukemia (CLL) from other mature B-cell neoplasms. However, it showed limitations in Asian patients. Therefore, we conducted a new score system replacing CD5 and CD23 with CD43 and CD180 to evaluate its diagnostic value of CLL. 237 untreated samples diagnosed with mature B-cell neoplasms were collected and were randomly divided into an exploratory and a validation cohort by a 2:1 ratio. The expression of CD5, CD19, CD20, CD23, CD43, CD79b, CD180, CD200, FMC7, and surface immunoglobulin (SmIg) were analyzed among all the samples. A proposed score was developed based on the logistic regression model. The sensitivity and specificity of the proposed score were calculated by ROC curves. CD43/CD180, CD200, FMC7, and CD79b were included in our new CLL score, which showed a sensitivity of 91.8% and a specificity of 83.1%. These results were confirmed in a validation cohort with a sensitivity of 90.5% (p = 0.808) and a specificity of 79.5% (p = 0.639). In CD5 negative or CD23 negative CLL group, the new CLL score displayed improved sensitivity of 79.4% compared to Moreau score and CLLflow score (41.2% and 47.1%, respectively). In atypical CLL group, the new CLL score showed improved sensitivity of 84.2% compared to Moreau score and CLLflow score (61.4% and 64.9%, respectively). This proposed atypical CLL score helped to offer an accurate differentiation of CLL from non-CLL together with morphological and molecular methods, particularly in Chinese patients with atypical immunophenotype.

Keywords: atypical; chronic lymphocytic leukemia; flow cytometry; immunophenotype.

Gene differential expression studies can serve to explore and understand the laws and characteristics of animal life activities, and the difference in gene expression between different animal tissues has been well demonstrated and studied. However, for the world-famous rare and protected species giant panda (Ailuropoda melanoleuca), only the transcriptome of the blood and spleen has been reported separately. Here, in order to explore the transcriptome differences between the different tissues of the giant panda, transcriptome profiles of the heart, liver, spleen, lung, and kidney from five captive giant pandas were constructed with Illumina HiSeq 2500 platform. The comparative analysis of the intertissue gene expression patterns was carried out based on the generated RNA sequencing datasets. Analyses of Gene Ontology (GO) enrichment, Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment, and protein-protein interaction (PPI) network were performed according to the identified differentially expressed genes (DEGs). We generated 194.52 GB clean base data from twenty-five sequencing libraries and identified 18,701 genes, including 3492 novel genes. With corrected p value <0.05 and |log₂FoldChange| >2, we finally obtained 921, 553, 574, 457, and 638 tissue-specific DEGs in the heart, liver, spleen, lung, and kidney, respectively. In addition, we identified TTN, CAV3, LDB3, TRDN, and ACTN2 in the heart; FGA, AHSG, and SERPINC1 in the liver; CD19, CD79B, and IL21R in the spleen; NKX2-4 and SFTPB in the lung; GC and HRG in the kidney as hub genes in the PPI network. The results of the analyses showed a similar gene expression pattern between the spleen and lung. This study provided for the first time the heart, liver, lung, and kidney's transcriptome resources of the giant panda, and it provided a valuable resource for further genetic research or other potential research.

Past decades of the current millennium have witnessed an unprecedented rise in Early age Onset of Colo Rectal Cancer (EOCRC) cases in India as well as across the globe. Unfortunately, EOCRCs are diagnosed at a more advanced stage of cancer. Moreover, the aetiology of EOCRC is not fully explored and still remains obscure. This study is aimed towards the identification of genes and pathways implicated in the EOCRC. In the present study, we performed high throughput RNA sequencing of colorectal tumor tissues for four EOCRC (median age 43.5 years) samples with adjacent mucosa and performed subsequent bioinformatics analysis to identify novel deregulated pathways and genes. Our integrated analysis identifies 17 hub genes (INSR, TNS1, IL1RAP, CD22, FCRLA, CXCL3, HGF, MS4A1, CD79B, CXCR2, IL1A, PTPN11, IRS1, IL1B, MET, TCL1A, and IL1R1). Pathway analysis of identified genes revealed that they were involved in the MAPK signaling pathway, hematopoietic cell lineage, cytokine-cytokine receptor pathway and PI3K-Akt signaling pathway. Survival and stage plot analysis identified four genes CXCL3, IL1B, MET and TNS1 genes (p = 0.015, 0.038, 0.049 and 0.011 respectively), significantly associated with overall survival. Further, differential expression of TNS1 and MET were confirmed on the validation cohort of the 5 EOCRCs (median age < 50 years and sporadic origin). This is the first approach to find early age onset biomarkers in Indian CRC patients. Among these TNS1 and MET are novel for EOCRC and may serve as potential biomarkers and novel therapeutic targets in future.

Cells expressing the surface markers CD3, CD4, CD79b, IgM, MHC class II, and ModoUG (nonclassical MHC class I) were detected in red-tailed phascogale tissues using immunohistochemistry, and the appearance and localization of cells observed here was consistent with previous observations in other marsupial species. CD3⁺ cells were first detected at one day postpartum (dpp) in the thymus, followed by ModoUG⁺ cells at 5-7 dpp in the thymus and lymph nodes. CD79b⁺ cells were first detected at 12-14 dpp in bone marrow, spleen, and lymph nodes. IgM⁺ cells were first detected at 12-14 dpp in thymus, bone marrow, spleen, and lymph nodes. MHC class II⁺ cells were first detected at 12-14 dpp in thymus, bone marrow, and lymph nodes. CD4⁺ cells were detected in adult thymus and spleen only. The presence of the mature immune cell populations and their localization to characteristic T and B cell zones in mature lymphoid tissues with normal histological structure indicates that red-tailed phascogales develop immunocompetence by the end of pouch life. Anat Rec, 2019. © 2019 Wiley Periodicals, Inc.

BACKGROUND

Trisomy 12 chronic lymphocytic leukemia (CLL) is phenotypically different from the rest of CLL cytogenetic subgroups. However, it is unknown whether this is also the case for trisomy 12 CLL-phenotype monoclonal B-cell lymphocytosis (MBL).

METHODS

We analyzed the expression of several markers in a series of 89 cytogenetically characterized MBL (including 17 trisomy 12 cases). Additionally, we compared the expression of these markers between trisomy 12 MBL, trisomy 12 CLL and a series of cases with trisomy 12 but fulfilling only 3 of the 5 Moreau CLL diagnostic criteria.

RESULTS

CD20, CD22 and CD79b were expressed more intensely in trisomy 12 MBL than in non-trisomy 12 MBL and there was a trend towards a dimmer expression of CD43 in trisomy 12 MBL. There were no differences between trisomy 12 CLL and trisomy 12 MBL. Expression of CD20 was dimmer and that of CD43 brighter in trisomy 12 MBL than in cases with trisomy 12 and 3 Moreau criteria.

CONCLUSIONS

In this study, trisomy 12 and non-trisomy 12 MBL were phenotypically different, but the differences are similar to those described between trisomy 12 and non-trisomy 12 CLL, suggesting that they are a distinct subgroup within CLL, given that the differences can already be found at its precursor stage. © 2017 International Clinical Cytometry Society.

Identification of prognostic factors in acute lymphoblastic leukemia (ALL) patients is important for stratifying patients into risk groups and tailoring treatment accordingly. Molecular and cytogenetic abnormalities are the most important prognostic factors. Minimal residual disease (MRD) is also an important predictor of relapse in ALL. However, the correlation of both prognostic variables has not been thoroughly studied.

We investigated the correlation between defined cytogenetic abnormalities and selected new MRD markers (CD79b, CD123, and CD200) in 56 newly diagnosed Egyptian pediatric B-cell ALL patients.

CD123 found to be expressed in 45% of patients, CD200 in 80.3%, and CD79b in 67.9%. MRD analysis during treatment showed stable expression patterns of CD200. There was significant association of CD123 expression with the hyperdiploid ALL group (P = .017). Another association (P = .029) was found between CD79b negativity and the t(12;21) group. CD200 was widely expressed in all groups.

There is a significant correlation between some markers, and certain ALL recurrent cytogenetic subgroups (CD123 and hyperdiploidy, CD79b negativity, and ETV-RUNX1 group) have good prognostic value. CD200 can be used as MRD markers in ALL patients and can also can serve as therapy targets.

OBJECTIVE

To analyze the prognostic factors for chronic lymphocytic leukemia (CLL) with typical and atypical immunophenotype. The parameters analyzed included sex, age, Binet stages, absolute lymphocyte count (ALC), immunoglobulin heavy-chain variable region (IgVH) gene mutation status, ZAP-70 protein, CD38 expression and cytogenetic aberrations.

METHODS

According to the clinical guideline and scoring system for CLL in Britain, among 77 patients, 61 patients with score 5 called typical immunophenotype CLL, 16 with score 4 or 3 were atypical immunophenotype CLL. Multiparameter flow cytometry was employed for immunophenotypic analysis in 77 CLL patients for CD5, CD19, CD23, FMC7, sIg, CD20, CD79b expression and ZAP-70 protein and CD38. IgVH mutation status was detected by multiplex RT-PCR and sequencing of the purified PCR amplification products. Fluorescence in situ hybridization (FISH) and a panel of probes were used to detect cytogenetic aberrations.

RESULTS

There was no significant difference between the two groups in sex, age, ZAP-70 and IgVH mutation status (P=0.398, P=0.189, P=0.268 and P=0.131, respectively). The incidence of ALC> or =50 x 10(9)/L, Binet B + C, CD38> or =30% in atypical CLL patients (43.8%, 87.5% and 43.8%, respectively) were higher than that in typical group (16.4%, 36.1% and 16.4%, respectively) (P=0.026, P<0.01 and P=0.026, respectively). The proportion of typical patients (26.8%) with a 13q14 deletion as sole abnormality was higher than that of atypical patients (7.6%), and that with deletion of 11q22 or 17p13 was lower than that of atypical patients (12.2% vs 46.2%) (P=0.022).

CONCLUSIONS

There were obvious differences between the typical immunophenotype CLL and atypical CLL in ALC, Binet stages, CD38 expression level and cytogenetic aberrations.

Background: Hairy cell leukaemia (HCL) is a rare lymphoproliferative disorder of B cell origin, and uncommonly it affects the lymph node. Fine needle aspiration cytology (FNAC) of lymph node of HCL has rarely been described.

Case description and diagnosis: A 41-year-old man presented with pallor, fever, tachycardia, generalized lymphadenopathy, and massive splenomegaly. The FNAC of the cervical lymph node was done. The smears showed many atypical lymphocytes with a plasmacytoid appearance. There were many large cells with round to reniform shaped nuclei having with hair-like cytoplasmic processes. Flow cytometry (FCM) revealed a clonal B cell population with light chain restriction and positive CD20, CD79b, CD22, CD11c, CD25, CD103, CD123, and CD200 markers.

Conclusion: The characteristic cytological features such as atypical lymphoid cells, large cells with hairy projections along with FCM findings, are helpful in the diagnosis of HCL.

Keywords: Hairy cell leukaemia; cytology; fine needle aspiration; lymph node.

To establish reference values of various immunophenotypic markers in B lymphocyte population in healthy Chinese adults and build background information for accurate interpretation of B cell immunophenotyping data in clinical practice, peripheral blood from 41 healthy adults were collected separately into test tubes containing EDTA-K(2) and stored in room temperature no more than 24 hours before analysis. Whole blood lysis technique and multiparameter flow cytometry were applied to immunophenotype B cells gated on CD19/SSC dot-plot. The results showed that CD22, CD20, CD62L, CD40, CD24, CD79b, CD79a, and FMC-7 were almost positive in the circulating B cell population, whereas CD11a, CD80, CD103, CD10, CD40L, CD54, CD95L, CD86, and CD95 were almost negative in the peripheral blood B lymphocytes. CD18, CD44, CD23, CD5, CD11c and CD43 were positive in different B cell subpopulations. 78% of B cells were IgD positive and ratio kappa/lambda was 1.26. The significance of all these markers in the differential diagnosis of lymphoproliferative diseases was discussed. The conclusion is that it is necessary to consider the qualitative and quantitative levels of expression of various markers in normal B cell population in order to accurately interpret the pathological immunophenotypic data in clinical practice. It is also important to note the immunotypic differences of B cells between Chinese and Western populations.

Flow-cytometric demonstration of the typical chronic lymphocytic leukemia (CLL) immunophenotype is vital for diagnosis. CLL has a characteristic immunophenotype, expressing CD5, CD19, dim CD20, dim CD22, CD23, bright CD43, dim CD45, dim to negative CD79b, dim CD81, CD200, and dim monoclonal surface immunoglobulin. This characteristic immunophenotype allows a definitive diagnosis and the ruling out of another leukemia or lymphoma. Flow cytometry also provides important prognostic information and accurate assessment of response to therapy. Here we describe optimal specimen collection, red cell lysis, appropriate panel, cell staining, acquisition on a flow cytometer, and analysis for CLL specimens.

Background. Extranodal marginal zone lymphoma of mucosa-associated lymphoid tissue (MALT) is a well-characterized entity that may share clinical and morphological findings with other low-grade non-Hodgkin's lymphomas. Dissemination of MALT-type lymphoma to bone marrow and peripheral blood simultaneously with the presence of T-large granular cell leukemia (T-LGL) has rarely been reported. Case Presentation. This is the case of a 42-year-old male who presented with a gastric MALT-type lymphoma, disseminated to the bone marrow and the peripheral blood with high serum IgM levels and t(11;18)(q21;q21). The morphological, immunophenotypical and, immunohistochemical studies of the successive bone marrow and peripheral blood samples had revealed the coexistence of two distinct lymphoma cell populations: a B-cell, marginal zone type population expressing CD19, CD20, CD22, CD79b, IgM, and kappa light chain, and a T-large granular cell population, developed after treatment with rituximab expressing CD3, CD8, CD5, CD7, and CD45. Conclusion. Based on the analysis of this unusual case we performed an extensive review of the literature to elucidate the relationship between T-LGL and B-cell lymphomas and to emphasize the importance of paraprotein analysis at diagnosis of gastric MALT lymphoma.

BACKGROUND

Chronic lymphocytic leukemia (CLL) is one of the commonest leukemias that has been reported extensively throughout the literature. The characteristic phenotype includes co-expression of CD5 and CD23, along with dim expression of light chain and CD22/CD79b, with lack of FMC7. The immunophenotypic scoring system given by Matutes has been used to differentiate CLL from non-CLL chronic lymphoproliferative disorders. Various aberrancies have been described in CLL cases, including abnormal (dim or bright) expression of B cell markers and lineage infidel T cell, myelomonocytic, or rarely Natural killer (NK) cells markers. However, the aberrant co-expression of CD56 and CD57 has not yet been reported.

RESULTS

We hereby report a case of 62-year female with a typical CLL phenotype and Matutes score of 5, showing the expression of CD56 and CD57.

CONCLUSIONS

This entity may represent a rare subtype of CLL which needs to be studied more extensively for its prognostic implications. This is the first report of CLL with aberrant CD56 and CD57 expression.

Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized aggressive disease commonly associated with Epstein-Barr virus (EBV) infection after hematopoietic stem cell transplantation (HSCT). Although rituximab (RTX) is incorporated into the first-line therapy for EBV-PTLD patients, the outcome of the clinically overt disease is still not optimal mainly due to the regrowth of tumor cells. The proliferation of CD20-/CD19+ tumor cells is increasingly reported in RTX-treated EBV-PTLD patients, whereas the emergence of CD20-/CD19- tumor cells is barely recognized. Here, we report a fatal case of an 18-year-old patient who developed EBV-PTLD after allogeneic HSCT for anaplastic large-cell lymphoma. On day 60 after HSCT, the patient developed abdominal pain, watery diarrhea, and low-grade fever. Colon biopsy revealed the proliferation of CD20+/CD19+/EBV-encoded RNA (EBER)+ tumor cells, and an increase of EBV DNA was detected in peripheral blood (PB). He was treated with RTX for EBV-PTLD and was cleared of EBV DNA in PB. However, he manifested high-grade fever, pancytopenia, and elevated soluble interleukin-2 receptor with a prominent hemophagocytosis in bone marrow aspirates and was treated with etoposide for hemophagocytic lymphohistiocytosis (HLH) complication. He then developed EBV DNA positivity in PB and finally died of Bacteroides fragilis sepsis subsequent to bloody stool and ileus on day 163. Autopsy revealed erosion and bleeding in the whole colon with the proliferation of CD20-/CD19-/EBER+ tumor cells. Immunohistochemical analysis uncovered the CD3-/CD56-/CD79a+/CD79b+ B-cell origin of tumor cells. This case clinically demonstrates the removal of both CD20 and CD19 antigens from EBER+ B cells in an RTX-treated EBV-PTLD patient with HLH complication.

Diffuse Large B-Cell lymphoma (DLBCL) is the most commonly diagnosed form of non-Hodgkin lymphoma (NHL) in adults. Most patients receive an initial treatment with chemo-immunotherapy, which includes rituximab, cyclophosphamide, vincristine, doxorubicin and prednisone (R-CHOP). Cure rates are high but those who relapse, or do not respond to initial therapy, have a poor prognosis. Polatuzumab vedotin, an anti-CD79b monoclonal antibody conjugated to the cytotoxic payload monomethyl aurostatin-E (MMAE), in combination with bendamustine and rituximab (polatuzumab-BR) is a new, effective therapeutic option to add to the treatment of relapsed/refractory (R/R) DLBCL Areas covered: This review covers the clinical development of polatuzumab for the treatment of lymphoma, its current and future use in patients with DLBCL and identifies its place in the treatment of R/R DLBCL. A search of PubMed and oncology/hematology congresses using "polatuzumab" as the search term was undertaken to identify the most pertinent clinical reports. Expert opinion: Polatuzumab-BR is an effective and safe option for transplant-ineligible patients with R/R DLBCL either before or after CAR-T (chimeric antigen receptor T-cell therapy). Ongoing combination trials with polatuzumab will expand its applications in the treatment of this disease.

Keywords: Antibody Drug Conjugate (ADC); Diffuse Large B Cell lymphoma; Lymphoma; Polatuzumab; Polatuzumab Vedotin; Rituximab; refractory DLBCL; relapsed DLBCL.

Enforced activation of NF-κB signaling can be achieved by constitutive NF-κB-inducing kinases, IKK2 and NIK, or via lymphoma-associated mutants of MYD88, CARD11, and CD79B. In order to model Diffuse Large B Cell Lymphoma (DLBCL) in mice, conditional alleles for these proteins are combined with alleles targeting Cre recombinase expression in mature B cells. However, unopposed NF-κB signaling promotes plasmablast differentiation, and as a consequence the model system must be complemented with further mutations that block differentiation, such as Prdm1/BLIMP1 inactivation or overexpression of BCL6. Here, we describe the currently available tools for DLBCL models in mice and their relative advantages and drawbacks. Furthermore, we describe methods to monitor lymphomagenesis, using ultrasound tomography of the spleen, and the technique of partial splenectomy surgery with recovery. These powerful techniques allow paired comparison of individual lymphoma cases before and after interventions, including therapies, and to study the evolution of lymphoma over time. NF-κB activation also promotes widespread nodal involvement with lymphoma and we describe the post-mortem dissection of major nodal groups.

Keywords: Diffuse large B cell lymphoma; Lymphoma evolution; NF-κB; Partial splenectomy; Relapse/refractory; Spleen ultrasound; Surgery; Therapy.

Despite substantially improved survival with rituximab-based treatment regimens, there is an unmet medical need for better treatments of B-cell lymphoma, particularly for patients with relapsed or refractory disease. Retreatment with rituximab exerts a limited effect in these patients, and platinum-based salvage treatment followed by autologous stem cell transplantation remains the only curative option. Recent strategies have focused on targeting novel B-cell surface markers, inhibiting B-cell receptor signaling, and enhancing the cytotoxicity of effector cells. The current article will review the recent progress in immunochemotherapy targeting other than CD20 for B-cell lymphomas.

Keywords: B-cell lymphoma; CD19; CD22; CD79b.

Vitreoretinal lymphoma (VRL) is a rare subtype of diffuse large B-cell lymphoma (DLBCL) considered a variant of primary central nervous system lymphoma (PCNSL). Diagnosis of VRL requires examination of vitreous fluid, but cytologic differentiation from uveitis remains difficult. Due to its rarity and difficulty in obtaining diagnostic material, little is known about the genetic profile of VRL. The aim of our study was to investigate the mutational profile of a large series of primary and secondary VRL. Targeted next generation sequencing using a custom panel containing the most frequent mutations in PCNSL was performed on 34 vitrectomy samples of 31 patients with VRL and negative controls with uveitis. In a subset of cases, genome-wide copy number alterations (CNA) were assessed using the Oncoscan platform. Mutations in MYD88 (74%), PIM1 (71%), CD79B (55%), IGLL5 (52%), TBL1XR1 (48%), ETV6 (45%) and 9p21/CDKN2A deletions (85%) were the most common alterations, with similar frequencies in primary (15), synchronous (3) or secondary (13) VRL. This mutational spectrum is similar to MYD88mut/CD79Bmut (MCD or cluster 5) DLBCL with activation of Toll-like and B-cell receptor pathways and CDKN2A loss, confirming their close relationship. Oncoscan analysis demonstrated a high number of CNAs (mean 18.6/case). Negative controls lacked mutations or CNAs. Using cell free DNA of vitreous fluid supernatant, mutations present in cellular DNA were reliably detected in all examined cases. Mutational analysis is a highly sensitive and specific tool for the diagnosis of VRL and can also be applied successfully to cell free DNA derived from the vitreous.

OBJECTIVE

We aimed to determine the hot spot mutational frequencies of Enhancer of Zeste homolog 2 (EZH2) and cluster of differentiation 79B (CD79B) genes in a cohort of mature B-cell non-Hodgkin's lymphomas.

METHODS

DNA samples from formalin-fixed and paraffin embedded (FFPE) tissues from a total of 37 patients with mature B-cell non-Hodgkin lymphomas were included in the study. Molecular genetic analysis was performed by direct sequencing of the DNA samples.

RESULTS

We analyzed formaldehyde fixed-paraffin embedded (FFPE) tumor tissue samples from 17 female and 20 male patients with a median age of 63.7 years at the time of diagnosis. None of the patients had previously reported hot spot mutations in EZH2 and CD79B, but previously unreported single nucleotide variations of CD79B were present in nine patients. rs779833118 was the most frequent variation (7/37 patients, 18.9%). A non-synonymous variation rs757407417, which could have a potentially damaging outcome, was detected in two patients.

CONCLUSIONS

None of the patients had well-known hot spot mutations in EZH2 and CD79B. However, we detected novel CD79B variations in mature B-cell non-Hodgkin's lymphoma patients.

Purpose: Primary central nervous system lymphoma (PCNSL) is a rare type of non-Hodgkin lymphoma. Previous studies have identified MYD88, CD79b and PIM1 as the most common genetic mutations in PCNSL. The extent to which mutations vary by ethnicity is unknown. The purpose of this study was to describe differences in genetic mutations and survival by Hispanic ethnicity in PCNSL.

Methods: 30 patients with PCNSL were examined for mutations in 275 genes by DNA analysis and 1408 genes by RNA analysis utilizing next generation sequencing.

Results: 60% of patients were Hispanic. 125 different mutated genes were detected. The most commonly affected genes were: MYD88 (44%), CARD11 (21%), CD79b (17%), PIM1 (17%) and KMT2D (17%) . MYD88 mutation was less frequent in Hispanic patients (27% vs 66%, P=.02). More Hispanic patients had >3 mutated genes (89% vs 55 %. P=.03). Two-year progression-free survival (PFS) and overall survival (OS) in Hispanic vs. non-Hispanic patients (PFS 60% vs 27%, P=.09), (OS 60% vs 36%, P=.23). MYD88, CARD11, PIM1, and KMT2D were not associated with significant differences in OS or PFS. CD79b mutation correlated with superior 2-yr PFS (P=.04).

Conclusions: We identified highly recurrent genetic alterations in PCNSL. Our data suggest that heterogeneity in some mutations may be related to ethnicity. There was no statistically significant difference in 2-yr PFS and OS in our Hispanic patients. Studies on larger population may further help to describe differences in tumor biology, and outcomes in Hispanic patients.

Keywords: Gene mutations; Hispanic; Next generation sequencing; Primary central nervous system lymphoma.

CD20-based monoclonal antibodies have become established as treatments for lymphoma, rheumatoid arthritis, systemic lupus erythematosus, vasculitis and dermatomyositis, with the principle therapeutic mechanism relating to B-cell depletion through effector cell engagement. An article by Brühl et al. in this issue of the European Journal of Immunology [Eur. J. Immunol. 2015. 45: 705-715] reveals a fundamentally distinct mechanism of silencing autoimmune B-cell responses. Rather than B-cell depletion, the authors use anti-CD79b antibodies to induce B-cell tolerance and suppress humoral immune responses against collagen to prevent the development of arthritis in mice. Here we highlight the differences in the mechanisms used by anti-CD20 and anti-CD79b Ab therapy and discuss why depletion of B cells may not be required to treat autoimmune arthritis and other B-cell-associated pathologies.

We present the case of a 65 years old male, admitted in the Hematology Department of the Universitary Emergency Hospital Bucharest, complaining of physical asthenia and weight loss; periodical medical examination has revealed splenomegaly and leucocytosis with lymphocytosis, persistent for the past 3 years. The clinical and paraclinical exam demonstrated splenomegaly (21 cm in diameter on computer tomography scan), hepatomegaly and generalized lymphadenopathies. The laboratory tests confirmed leucocytosis with lymphocytosis--a clonal population of B lymphocytes CD20+ CD19+ CD23+/- CD79b+(low), CD43+ FMC7+ CD5+ CD38+ ZAP70+ cyclin D1-. Lymph node and bone marrow biopsy together with flowcytometry established the diagnosis of Malignant non-Hodgkin Lymphoma--Atypical Splenic Marginal Zone B-cell lymphoma (aberrant expression of CD5) stage IVB, with leukemic picture, complicated with autoimmune hemolytic anemia with highly positive Coombs' tests. We performed therapeutic splenectomy, which was difficult because of the dimensions of the organ. The short term evolution was complicated by acute complete thrombosis of the splenic vein, but the long term evolution (1 year follow-up) was favorable--remission of anemia, significant improvement of performance status, decrease of leucocytosis and reduction of the tumoral mass.

Recent classifications of non-Hodgkin's lymphomas based on combination of morphologic, immunophenotypic, and cytogenetic criteria have individualized mantle cell lymphoma (MCL). This clinico-biological entity which accounts for 3 to 10% of all non-Hodgkin's lymphomas, now appears to be a biological and therapeutic model for the understanding and treatment of hematologic malignancies. The present study consisting of two cases of MCL collated at laboratory of hematology of Rabat Ibn Sina hospital. The morphological appearance of MCL is characterized by diffuse or nodular lymph infiltration in the mantle zone, the osteo-medullary biopsy shows an interstitial infringement characterized by the presence of lymphocytes resembling centrocytes with cleaved and angular nuclei, dispersed chromatin, inconspicuous nucleoli and scanty cytoplasm. The flow cytometry showed immunophenotype positive for surface Ig, CD19, CD20, CD22, CD79b, CD5 and cyclin D1, and negative for CD10, CD23 and CD25. In conclusion, the methods of diagnosis and prognosis evaluation of mantle cell lymphoma are based on the nodular, medullary and blood morphology, the immunophenotypic, cytogenetic and molecular study of neoplastic cells.

Myeloid disorders, especially myelodysplastic syndrome (MDS) and acute myeloid leukemia (AML), cause significant mobility and high mortality worldwide. Despite numerous attempts, the common molecular events underlying the development of MDS and AML remain to be established. In the present study, 18 microarray datasets were selected, and a meta-analysis was conducted to identify shared gene signatures and biological processes between MDS and AML. Using NetworkAnalyst, 191 upregulated and 139 downregulated genes were identified in MDS and AML, among which, PTH2R, TEC, and GPX1 were the most upregulated genes, while MME, RAG1, and CD79B were mostly downregulated. Comprehensive functional enrichment analyses revealed oncogenic signaling related pathway, fibroblast growth factor receptor (FGFR) and immune response related events, 'interleukine-6/interferon signaling pathway, and B cell receptor signaling pathway', were the most upregulated and downregulated biological processes, respectively. Network based meta-analysis ascertained that HSP90AA1 and CUL1 were the most important hub genes. Interestingly, our study has largely clarified the link between MDS and AML in terms of potential pathways, and genetic markers, which shed light on the molecular mechanisms underlying the development and transition of MDS and AML, and facilitate the understanding of novel diagnostic, therapeutic and prognostic biomarkers.