BACKGROUNDGene rearrangements and specific translocations define some B‐cell non‐Hodgkin lymphoma (NHL) subtypes. Genome‐wide mutational studies have revealed recurrent point mutations with prognostic implications. The goals of this study were to evaluate the feasibility of applying a multiplex mutation assay to archival cytospin preparations (CPs) and to investigate the rate of EZH2, CD79B, and MYD88 mutations in B‐cell NHL samples previously tested for MYC rearrangement and/or IGH/BCL‐2 translocation.METHODSDNA was extracted from archival CPs of B‐cell NHL cases with previous fluorescence in situ hybridization (FISH) assays for MYC rearrangement and/or IGH/BCL‐2 translocation. Multiplex sequencing was performed for the detection of EZH2 (Y641), CD79B (Y196), and MYD88 (L265) mutations. Sanger sequencing was applied to samples with positive results and failed assays.RESULTSEighty‐eight archival CPs were available from 40 patients. Alterations detected by FISH were: MYC rearrangement (10 cases), IGH/BCL‐2 translocations (21 cases), dual translocations (6 cases), and other abnormalities for IGH/BCL‐2 (23 cases) and for MYC (16 cases). DNA concentration ranged from 1.88 to 62.85 ng/µL (mean, 9.46 ng/µL). Successful results were obtained in 88.0% of the specimens submitted to multiplex sequencing. With Sanger sequencing, 2 additional mutated cases were found, and all cases with mutations were confirmed. Eight specimens showed mutations: 6 for EZH2, 1 for CD79B, and 1 for MYD88. Among them, 5 cases showed concurrent MYC and/or IGH/BCL‐2 translocations and 2 revealed abnormal signals of IGH/BCL‐2 and MYC.CONCLUSIONSCPs archived for up to 6 years are a reliable source of high‐quality genomic material for multiplex sequencing. Almost all B‐cell NHL with point mutations showed concurrent chromosomal abnormalities. Cancer (Cancer Cytopathol) 2015;123:413‐20. © 2015 American Cancer Society.

The ETV6/FLT3 fusion gene has been recently reported in association with myeloproliferative neoplasm with eosinophilia (MPN-Eo) and peripheral T cell lymphoma. Favorable clinical response to a targeted FLT3 tyrosine kinase inhibitor (FLT3 TKI) was noted. Here we report a novel phenotype associated with ETV6/FLT3 rearrangement, in a 38-year-old female with presentation of progressive lymphadenopathy. Lymph node biopsy showed mixed-phenotype acute leukemia (MPAL) with expression of T cell and myeloid markers. Bone marrow morphology was consistent with MPN-Eo and no evidence of MPAL. Karyotype analysis revealed 46, XX, t(12;13)(p13;q12). ETV6/FLT3 fusion was demonstrated by fluorescence in situ hybridization. This is the first report of ETV6/FLT3 rearrangement showing a phenotype of extramedullary T/myeloid MPAL arising in the setting of MPN-Eo. We suggest addition of this entity to the WHO category of “myeloid/lymphoid neoplasms with eosinophilia,” particularly given the possibility of clinical response to FLT3 TKI in MPAL, a disease usually associated with poor prognosis.

PurposeMantle-cell lymphoma (MCL) has a variable natural history but is incurable with current therapies. MicroRNAs (miRs) are useful in prognostic assessment of cancer. We determined an miR signature defining aggressiveness in B-cell non-Hodgkin lymphomas (NHL) and assessed whether this signature aids in MCL prognosis.MethodsWe assessed miR expression in a training set of 43 NHL cases. The miR signature was validated in 44 additional cases and examined on a training set of 119 MCL cases from four institutions in Canada. miRs significantly associated with overall survival were examined in an independent cohort of 114 MCL cases to determine association with patient outcome. miR expression was combined with current clinical prognostic factors to develop an enhanced prognostic model in patients with MCL.ResultsFourteen miRs were differentially expressed between aggressive and indolent NHL; 11 of 14 were validated in an independent set of NHL (excluding MCL). miR-127-3p and miR-615-3p were significantly associated with overall survival in the MCL training set. Their expression was validated in an independent MCL patient set. In comparison with Ki-67, expression of these miRs was more significantly associated with overall survival among patients with MCL. miR-127-3p was combined with Ki-67 to create a new prognostic model for MCL. A similar model was created with miR-615-3p and Mantle Cell Lymphoma International Prognostic Index scores.ConclusionEleven miRs are differentially expressed between aggressive and indolent NHL. Two novel miRs were associated with overall survival in MCL and were combined with clinical prognostic models to generate novel prognostic data for patients with MCL.

BACKGROUNDNumerous genomic abnormalities in B‐cell non‐Hodgkin lymphomas (NHLs) have been revealed by novel high‐throughput technologies, including recurrent mutations in EZH2 (enhancer of zeste homolog 2) and CD79B (B cell antigen receptor complex‐associated protein beta chain) genes. This study sought to determine the evolution of the mutational status of EZH2 and CD79B over time in different samples from the same patient in a cohort of B‐cell NHLs, through use of a customized multiplex mutation assay.METHODSDNA that was extracted from cytological material stored on FTA cards as well as from additional specimens, including archived frozen and formalin‐fixed histological specimens, archived stained smears, and cytospin preparations, were submitted to a multiplex mutation assay specifically designed for the detection of point mutations involving EZH2 and CD79B, using MassARRAY spectrometry followed by Sanger sequencing.RESULTSAll 121 samples from 80 B‐cell NHL cases were successfully analyzed. Mutations in EZH2 (Y646) and CD79B (Y196) were detected in 13.2% and 8% of the samples, respectively, almost exclusively in follicular lymphomas and diffuse large B‐cell lymphomas. In one‐third of the positive cases, a wild type was detected in a different sample from the same patient during follow‐up.CONCLUSIONSTesting multiple minimal tissue samples using a high‐throughput multiplex platform exponentially increases tissue availability for molecular analysis and might facilitate future studies of tumor progression and the related molecular events. Mutational status of EZH2 and CD79B may vary in B‐cell NHL samples over time and support the concept that individualized therapy should be based on molecular findings at the time of treatment, rather than on results obtained from previous specimens. Cancer (Cancer Cytopathol) 2013;121:377–386. © 2013 American Cancer Society.

Abstract 1586 Background Mantle cell lymphoma (MCL) is a subtype of B-cell non-Hodgkin lymphoma (NHL) characterized by the t(11;14) translocation and concomitant over-expression of cyclin D1. MCL has a variable natural history; while some patients have prolonged survival similar to other indolent B-cell lymphomas, most follow an aggressive course with short survival. While the t(11;14) is pathognomonic of MCL, it is not necessary for disease pathogenesis, as a subset of MCL cases lack the translocation. Furthermore, in vivo models demonstrate that cyclin D1 over-expression alone is unable to bring about the disease, and that deregulation of additional cellular pathways is required for its pathogenesis. Assessment of microRNA (miR) expression in MCL may help determine mechanisms of gene deregulation and reveal pathways involved in disease pathogenesis. In this study we examined MCL in relation to both aggressive and indolent B-cell NHL to determine a miR signature that characterizes MCL. Design and Methods Total RNA from a training set of 36 B-cell NHL cases (19 indolent and 17 aggressive) and 32 MCL was applied to a high-throughput quantitative real-time PCR platform assessing the expression of 365 miRs [TaqMan Human MicroRNA Array v1.0 (Early Access) or TLDA]. miRs that were differentially expressed between MCL and aggressive NHL, and between MCL and indolent NHL were then validated using RNA from a second, independent, set of B-cell NHL cases (28 indolent and 28 aggressive) and 50 MCL cases. Validated miRs were determined and potential targets for each miR were examined. A map of targets common to the MCL miR signature was created, revealing important proteins involved in MCL pathogenesis. Results 66 miRs (11 over-expressed, 55 under-expressed) were differentially expressed between MCL and aggressive B-cell NHL and 8 miRs (7 over-expressed, 1 under-expressed) were differentially expressed between MCL and indolent B-cell NHL (false discovery rate = 0.2). 6 miRs from each group were chosen for validation in an independent set of MCL and NHL cases. Of these 12 miRs, 7 miRs validated (2 were under-expressed in MCL relative to aggressive B-cell NHL, and 5 were over-expressed in MCL relative to indolent B-cell NHL). Genes and pathways involved in disease pathogenesis are most likely targeted by multiple miRs. We thus determined a set of 123 genes predicted to be targets of this MCL miR signature, based on five miR target prediction databases from the mirDIP (microRNA data integration) portal. These genes were significantly enriched for focal adhesion and integrin signalling, proteasome-mediated degradation, and the PI3K signalling pathway. Conclusions Using the largest set of MCL cases evaluated to date, a 7-miR signature characteristic of MCL was discovered. The gene targets of these miRs are enriched for roles in proteasome-mediated protein degradation, consistent with the reported sensitivity of MCL to proteasome inhibitors. In addition, these miRs are predicted to be involved in regulation of PI3K/AKT signalling, confirming reports of the importance of this pathway in MCL pathogenesis. Enrichment of target genes involved in focal adhesion and integrin signalling indicate the importance of MCL-stromal interactions and motivates further study into the role of the tumor microenvironment in MCL pathogenesis. Disclosures: No relevant conflicts of interest to declare.

Post-transplant lymphoproliferative disorders (PTLD) are the second most frequent neoplasia in transplant patients after skin carcinomas. They occur following both solid organ transplants (SOT) and haematopoietic stem cell transplants (HSCT). Most PTLD in solid organ recipients are of host origin, whereas in HSCT recipients they are most often of donor origin. The EBV status of the recipient and the donor, the type of transplant, the type of immunosuppressive therapy used, and the time after transplant are all important parameters that have been associated with the incidence and the type of PTLD. Although most PTLD are B-cell lesions up to 15% may be T-cell or NK-cell type. Most PTLD are associated with EBV, but EBV-negative PTLD are also clearly recognized. In the 2008 WHO classification of lymphoid neoplasms (ref) PTLD are subclassified according to their histological and immunophenotypic characteristics into early lesions, polymorphic type, monomorphic type, and classical Hodgkin lymphoma-type. Overall PTLD mortality rates are around 50%, but new therapies that include early treatment with rituximab and novel anti-EBV therapies promise better outcomes.

B‐cell lymphomas with concurrent IGH/BCL2 and MYC gene rearrangements, termed dual‐translocation or double‐hit lymphomas (DTLs), rarely are identified. They usually are characterized by highly aggressive behavior, a poor prognosis, and complex karyotypes. The objective of this study was to review and describe the cytomorphologic findings in different types of cytologic preparations and clinicopathologic characteristics of patients with DTLs.

OBJECTIVE:To determine which measure of the salivary flow rate, stimulated or unstimulated, is most strongly associated with pathologic changes in minor salivary gland (MSG) biopsy specimens, and to explore the correlation of salivary flow with oral surface damage, disease duration, and symptom severity in patients with primary Sjögren's syndrome (SS).METHODS:In all patients (n = 32), a biopsy of the MSG was performed, and stimulated salivary flow was assessed. Beginning in 2002, unstimulated salivary flow was also assessed. Scores for the severity of symptoms, according to the decayed/missing/filled teeth (DMF) index, were recorded. Associations between measures of salivary flow and covariates characterizing pathology were examined.RESULTS:A definite association between stimulated salivary flow and the MSG focus score, the grade of MSG fibrosis, the duration of dry mouth symptoms, and the DMF score was observed. In contrast, unstimulated salivary flow was not associated with fibrosis, atrophy, the DMF score, or the duration of dry mouth symptoms. In patients with primary SS, the DMF score was associated with pathologic changes in the MSG. Among patients with sicca, 57.9% had an abnormal unstimulated salivary flow rate (versus 82.4% of patients with primary SS), and 15.2% had an abnormal stimulated salivary flow rate (versus 61.8% of patients with primary SS). Among patients with sicca, neither stimulated salivary flow nor unstimulated salivary flow was associated with the degree of fibrosis or atrophy or with the DMF score.CONCLUSION:Compared with unstimulated salivary flow, stimulated salivary flow appeared to be a better measure of inflammation (according to the focus score) and fibrosis. In patients with sicca, the unstimulated salivary flow rate appeared to be abnormal more commonly compared with the stimulated salivary flow rate. In the future, stimulated salivary flow may serve as a noninvasive surrogate biomarker of inflammation and fibrosis as well as a measure of response to treatment in patients with primary SS.

Two cases are described of crystal storing histiocytosis (CSH) associated with extranodal marginal zone lymphoma, presenting as lung and subcutaneous masses respectively. Fine-needle aspiration of subcutis and smears prepared from the resected lung masses showed negative images. Cytology slides of both cases were reviewed to identify cytomorphological features for the differential diagnosis between immunoglobulin crystals and mycobacteria. The crystals in CSH consist of straight and needle shaped rods with pointed or angular edges and are more variable in thickness than the uniformly thin mycobacteria. Mycobacteria show a haphazard distribution, whereas crystals are frequently present in parallel arrays. Small lymphoid or plasma cells are identified in the background of CSH, whereas a necrotic and inflammatory background is seen in mycobacteriosis. Additional samples for culture in the case of mycobacteriosis, or flow cytometry and molecular clonality testing in the case of CSH can provide critical data for a definitive diagnosis.

Background MicroRNAs (miRs) are non-coding RNA molecules involved in post-transcriptional regulation, with diverse functions in tissue development, differentiation, cell proliferation and apoptosis. miRs may be less prone to degradation during formalin fixation, facilitating miR expression studies in formalin-fixed paraffin-embedded (FFPE) tissue. Results Our study demonstrates that the TaqMan Human MicroRNA Array v1.0 (Early Access) platform is suitable for miR expression analysis in FFPE tissue with a high reproducibility (correlation coefficients of 0.95 between duplicates, p < 0.00001) and outlines the optimal performance conditions of this platform using clinical FFPE samples. We also outline a method of data analysis looking at differences in miR abundance between FFPE and fresh-frozen samples. By dividing the profiled miR into abundance strata of high (Ct<30), medium (30≤Ct≤35), and low (Ct>35), we show that reproducibility between technical replicates, equivalent dilutions, and FFPE vs . frozen samples is best in the high abundance stratum. We also demonstrate that the miR expression profiles of FFPE samples are comparable to those of fresh-frozen samples, with a correlation of up to 0.87 (p < 0.001), when examining all miRs, regardless of RNA extraction method used. Examining correlation coefficients between FFPE and fresh-frozen samples in terms of miR abundance reveals correlation coefficients of up to 0.32 (low abundance), 0.70 (medium abundance) and up to 0.97 (high abundance). Conclusion Our study thus demonstrates the utility, reproducibility, and optimization steps needed in miR expression studies using FFPE samples on a high-throughput quantitative PCR-based miR platform, opening up a realm of research possibilities for retrospective studies.

Purpose. The purpose of this study was to use factor analysis to analyze 90 clinical characteristics of a cohort of 231 patients with primary Sjogren syndrome (pSS). Methods. The records of all patients seen at the University Health Network Sjogren Syndrome Clinic from October 1992 to July 2006 were reviewed and documented. Those diagnosed as pSS by the American European Consensus Criteria of 2002 were included. The 90 clinical variables, including health history, blood analysis, symptoms of dry eye and dry mouth, salivary flow and biopsy, tear flow and staining, were analyzed by factor analysis. Results. Two hundred thirty-one patients with pSS charts were reviewed, and 90 variables were recorded. Factor analysis resulted in three factors: factor 1: ocular surface staining, factor 2: antimicrosomal antibodies and antithyroid antibodies, and factor 3: serum anti-Ro and anti-La. Conclusions. Ocular surface staining accounted for the greatest variance in this population of patients with pSS.

MIB‐1 proliferation index (PI) has proven helpful for diagnosis and prognosis in non‐Hodgkin lymphomas (NHLs). However, validated cutoff values for use in fine‐needle aspiration (FNA) samples are not available. We investigated MIB‐1 immunocytochemistry as an ancillary technique for stratifying NHL and attempted to establish PI cutpoints in cytologic samples.