New approaches to lymphoma diagnosis

Combined detection of lymphocyte clonality and MALT1 translocations in bronchoalveolar lavage fluid for diagnosing pulmonary lymphomas

Diagnosis of pulmonary lymphoma using small tissue samples is difficult and often requires surgical procedures; thus, a less invasive sampling method is desirable. We previously showed that pulmonary mucosa-associated lymphoid tissue (MALT) lymphoma can be diagnosed by detecting MALT lymphoma translocation gene 1 (MALT1) translocations in bronchoalveolar lavage fluid (BALF) cells. Analysis of B-cell clonality based on immunoglobulin heavy chain (IGH) gene rearrangements was also reportedly useful for diagnosing pulmonary lymphoma. The aim of this prospective multicenter study was to evaluate the yet unknown diagnostic potential of combined detection of MALT1 translocations and clonality using BALF. We analyzed B- and T-cell clonality based on IGH and T-cell receptor (TCR) rearrangements together with MALT1 translocations using BALF of patients with clinically suspected pulmonary lymphomas. In total, 39 patients were evaluated and categorized into three groups: B-cell lymphoma, lymphoproliferative disorders, and other diseases. IGH rearrangement detection for B-cell lymphoma diagnosis exhibited sensitivity and specificity of 88.9% and 90.0%, respectively. TCR rearrangements were not observed in patients with B-cell lymphomas. The presence of IGH rearrangements together with the absence of TCR rearrangements indicated 96.0% specificity for the diagnosis of B-cell lymphoma. The sensitivity and specificity of MALT1 translocations for diagnosing MALT lymphoma were 28.6% and 100%, respectively. The combined detection of lymphocyte clonality and MALT1 translocations using BALF is suitable for screening and diagnosis of B-cell lymphomas. Analysis of specific genes such as MALT1 should improve the precision of B-cell lymphoma diagnosis.

Population Pharmacokinetics of Blinatumomab in Pediatric and Adult Patients with Hematological Malignancies

BACKGROUND AND OBJECTIVES

Blinatumomab (BLINCYTO^®) is a novel bispecific T cell engager (BiTE^®) approved in the USA for the treatment of relapsed or refractory B cell precursor acute lymphoblastic leukemia (ALL) in children and adults, as well as minimal residual disease ALL in adults. This analysis characterized the population pharmacokinetics of intravenous blinatumomab in pediatric and adult patients.

METHODS

A total of 2417 serum concentrations of blinatumomab from 674 patients, including adult (n = 628) and pediatric patients (n = 46), from eight clinical studies were analyzed. The impact of covariates on pharmacokinetic parameters were explored, and significant covariates were further evaluated using a simulation approach.

RESULTS

Blinatumomab pharmacokinetics were described by a one-compartment linear model with first-order elimination, a clearance (CL) of 2.22 L/h, and a central volume of 5.98 L. A statistically significant effect of body surface area (BSA) on CL was observed. The smallest BSA of 0.37 m² in the pediatric population was associated with a 63% reduction in blinatumomab systemic CL, relative to an adult patient with the median BSA (1.88 m²), supporting the use of BSA-based dosing in patients of lower bodyweight. The BSA effect was minimal, with a ≤ 25% change in CL over the range of BSA in adults, supporting no need for BSA-based dosing.

CONCLUSIONS

Blinatumomab pharmacokinetics were adequately described by a one-compartment linear model with first-order elimination. No covariates other than BSA on CL were identified as significant. BSA-based dosing should be considered for lightweight patients to minimize inter-subject variability in blinatumomab exposure.

Orbital and Eyelid B-Cell Lymphoma: A Multicenter Retrospective Study

Simple Summary

The treatment of orbital and eyelid B-cell lymphoma remains a field of progress. The aim of our study was to analyze patients diagnosed, staged and treated for orbital and eyelid B-cell lymphoma to assess clinical characteristics, treatment outcomes and recurrence patterns. We included in this study 141 cases of orbital and eyelid B-cell lymphoma. We found five lymphoma subtypes and we confirmed that the histopathologic subtype and the type of treatment were found to be the main factors influencing treatment outcome.

Abstract

Background: The aim of this study was to analyze patients diagnosed, staged and treated for orbital and eyelid B-cell lymphoma (OEL). Methods: One hundred and forty-one cases of OEL were included in this study. Primary endpoints were to analyze the histopathologic findings, the main risk factors and the type of treatment and to correlate them with recurrence of OEL. The secondary endpoint was to determine the progression-free survival (PFS) time. Results: Extranodal marginal zone B-cell lymphoma was the most frequent subtype (66%), followed by small lymphocytic lymphoma (12.7%), diffuse large B-cell lymphoma (DLBCL) (9.2%), follicular lymphoma (6.6%), mantle cell lymphoma (4.3%) and Burkitt lymphoma (1.2%). The probability of relapse was influenced by the histopathologic subtype DLBCL (OR = 7.7, 95% CI 1.8–32.3) and treatment with chemotherapy (OR = 14.9, 95% CI 2.6–83.7). Multivariate analysis showed that the histopathologic subtype DLBCL and chemotherapy treatment retained statistical significance for a poorer PFS, with hazard ratios of 8.581 (p = 0.0112) and 9.239 (p = 0.0094), respectively. Conclusions: Five lymphoma subtypes were found in patients with OEL. The histopathologic subtype and the type of treatment were found to be the main factors influencing treatment outcome.

Age-Related Gliosis Promotes Central Nervous System Lymphoma through CCL19-Mediated Tumor Cell Retention

How lymphoma cells (LCs) invade the brain during the development of central nervous system lymphoma (CNSL) is unclear. We found that NF-κB-induced gliosis promotes CNSL in immunocompetent mice. Gliosis elevated cell-adhesion molecules, which increased LCs in the brain but was insufficient to induce CNSL. Astrocyte-derived CCL19 was required for gliosis-induced CNSL. Deleting CCL19 in mice or CCR7 from LCs abrogated CNSL development. Two-photon microscopy revealed LCs transiently entering normal brain parenchyma. Astrocytic CCL19 enhanced parenchymal CNS retention of LCs, thereby promoting CNSL formation. Aged, gliotic wild-type mice were more susceptible to forming CNSL than young wild-type mice, and astrocytic CCL19 was observed in both human gliosis and CNSL. Therefore, CCL19-CCR7 interactions may underlie an increased age-related risk for CNSL.

Serological Assessment of 18 Pathogens and Risk of AIDS-Associated Non-Hodgkin Lymphoma

BACKGROUND

HIV infection is associated with increased susceptibility to common pathogens, which may trigger chronic antigenic stimulation and hyperactivation of B cells, events known to precede the development of AIDS-associated non-Hodgkin lymphoma (AIDS-NHL).

METHODS

To explore whether cumulative exposure to infectious agents contributes to AIDS-NHL risk, we tested sera from 199 AIDS-NHL patients (pre-NHL, average lead time 3.9 years) and 199 matched HIV-infected controls from the Multicenter AIDS Cohort Study, for anti-IgG responses to 18 pathogens using multiplex serology. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression models.

RESULTS

We found no association between cumulative exposure to infectious agents and AIDS-NHL risk (OR 1.01, 95% CI: 0.91 to 1.12). However, seropositivity for trichodysplasia spinulosa polyomavirus (TSPyV), defined as presence of antibodies to TSPyV capsid protein VP1, was significantly associated with a 1.6-fold increase in AIDS-NHL risk (OR 1.62, 95% CI: 1.02 to 2.57). High Epstein-Barr virus (EBV) anti-VCA p18 antibody levels closer to the time of AIDS-NHL diagnosis (<4 years) were associated with a 2.6-fold increase in AIDS-NHL risk (OR 2.59, 95% CI: 1.17 to 5.74). In addition, high EBV anti-EBNA-1 and anti-ZEBRA antibody levels were associated with 2.1-fold (OR 0.47, 95% CI: 0.26 to 0.85) and 1.6-fold (OR 0.57, 95% CI: 0.35 to 0.93) decreased risk of AIDS-NHL, respectively.

CONCLUSIONS

Our results do not support the hypothesis that cumulative exposure to infectious agents contributes to AIDS-NHL development. However, the observed associations with respect to TSPyV seropositivity and EBV antigen antibody levels offer additional insights into the pathogenesis of AIDS-NHL.

Case report of subcutaneous panniculitis-like T-cell lymphoma complicated by eyelid swelling

BACKGROUND

Subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is a rare, highly malignant, extranodal lymphoma that preferentially infiltrates into subcutaneous adipose tissue. No case of SPTCL with the earliest symptoms occurring in the eye region has been reported. We report a case of SPTCL complicated by eyelid swelling.

CASE PRESENTATION

A 19-year-old Japanese man presented with worsening left eyelid swelling. The patient's best-corrected visual acuity (BCVA) was 0.8, left intraocular pressure was 36 mm Hg, and he had prominent mucosal hyperemia and edema. His left eye had light reflex attenuation and a positive relative afferent pupillary defect, but no abnormality in the visual field or central flicker value. Magnetic resonance imaging showed left orbital adipose tissue inflammation. The blood examination was normal. He was hospitalized for an intensive examination and treatment for possible cellulitis, orbital panniculitis, and inflammatory pseudotumor. Systemic antibiotics were initiated. The following day, he underwent a sub-Tenon's injection of triamcinolone. Left eyelid swelling gradually improved. He was discharged on the ninth day and followed up with oral prednisolone. Two months later, he visited our department because of a high fever and slight right eyelid swelling. Ocular hypertension was detected. A blood examination revealed pancytopenia. Computed tomography showed fluid retention, hydrothorax, and abdominal dropsy. Magnetic resonance imaging revealed right orbital panniculitis. Because of suspected hemodyscrasia, he was referred to the hematology department of another hospital where he was diagnosed with SPTCL.

CONCLUSIONS

The possibility of SPTCL, with attention to recurrence and systemic symptoms, should be considered in young patients with sudden eyelid swelling.

Lymphohematopoietic cancers induced by chemicals and other agents and their implications for risk evaluation: An overview

Lymphohematopoietic neoplasia are one of the most common types of cancer induced by therapeutic and environmental agents. Of the more than 100 human carcinogens identified by the International Agency for Research on Cancer, approximately 25% induce leukemias or lymphomas. The objective of this review is to provide an introduction into the origins and mechanisms underlying lymphohematopoietic cancers induced by xenobiotics in humans with an emphasis on acute myeloid leukemia, and discuss the implications of this information for risk assessment. Among the agents causing lymphohematopoietic cancers, a number of patterns were observed. Most physical and chemical leukemia-inducing agents such as the therapeutic alkylating agents, topoisomerase II inhibitors, and ionizing radiation induce mainly acute myeloid leukemia through DNA-damaging mechanisms that result in either gene or chromosomal mutations. In contrast, biological agents and a few immunosuppressive chemicals induce primarily lymphoid neoplasms through mechanisms that involve alterations in immune response. Among the environmental agents examined, benzene was clearly associated with acute myeloid leukemia in humans, with increasing but still limited evidence for an association with lymphoid neoplasms. Ethylene oxide and 1,3-butadiene were linked primarily to lymphoid cancers. Although the association between formaldehyde and leukemia remains controversial, several recent evaluations have indicated a potential link between formaldehyde and acute myeloid leukemia. The four environmental agents examined in detail were all genotoxic, inducing gene mutations, chromosomal alterations, and/or micronuclei in vivo. Although it is clear that rapid progress has been made in recent years in our understanding of leukemogenesis, many questions remain for future research regarding chemically induced leukemias and lymphomas, including the mechanisms by which the environmental agents reviewed here induce these diseases and the risks associated with exposures to such agents.

Multiple primary enoral soft tissue manifestations of a Hodgkin lymphoma--case report and literature review

BACKGROUND

Hodgkin lymphoma (HL) are lymphoproliferative neoplasms, histologically comprising of mononuclear and multinucleated Hodgkin and Reed Sternberg cells (HRS). About 4 % of all lymphatic malignancies of the head and neck are HL. The typical disease presents itself as a nodal lesion. Extranodal, enoral soft tissue involvement by HL is very rare.

CASE REPORT

A 73-year-old man with a suspect, ulcerating lesion in the left retromolar region of the mandible was assigned to our hospital. Prior anti-inflammatory therapy has been without success. Subsequently, three biopsies were taken which could only show inflammation. Finally, two biopsies from the left retromolar region and the left inner cheek showed HRS cells with positive expressions of CD15 and CD30 corresponding to a Hodgkin lymphoma. No lymphatic node or bone involvement could be detected. The patient was designated to receive radio-chemotherapy, but died 3 weeks after diagnosis of multiple organ failure. In a literature review, together with this report, nine cases were found concerning primary HL of the oral mucosa. Accordingly, this is the first case of primary multiple extranodal HL in the oral mucosa in absence of lymphatic node involvement.

DISCUSSION

Neither clinical features nor radiological appearances of HL presenting as primary enoral lesions are pathognomonic. Especially when only small biopsy specimens are available, histological diagnosis remains challenging, may lead to a delay in therapy and may result in a significant worse prognosis.

A Systematic Review of Carcinogenic Outcomes and Potential Mechanisms from Exposure to 2,4-D and MCPA in the Environment

Chlorophenoxy compounds, particularly 2,4-dichlorophenoxyacetic acid (2,4-D) and 4-chloro-2-methylphenoxy)acetic acid (MCPA), are amongst the most widely used herbicides in the United States for both agricultural and residential applications. Epidemiologic studies suggest that exposure to 2,4-D and MCPA may be associated with increased risk non-Hodgkins lymphoma (NHL), Hodgkin's disease (HD), leukemia, and soft-tissue sarcoma (STS). Toxicological studies in rodents show no evidence of carcinogenicity, and regulatory agencies worldwide consider chlorophenoxies as not likely to be carcinogenic or unclassifiable as to carcinogenicity. This systematic review assembles the available data to evaluate epidemiologic, toxicological, pharmacokinetic, exposure, and biomonitoring studies with respect to key cellular events noted in disease etiology and how those relate to hypothesized modes of action for these constituents to determine the plausibility of an association between exposure to environmentally relevant concentrations of 2,4-D and MCPA and lymphohematopoietic cancers. The combined evidence does not support a genotoxic mode of action. Although plausible hypotheses for other carcinogenic modes of action exist, a comparison of biomonitoring data to oral equivalent doses calculated from bioassay data shows that environmental exposures are not sufficient to support a causal relationship. Genetic polymorphisms exist that are known to increase the risk of developing NHL. The potential interaction between these polymorphisms and exposures to chlorophenoxy compounds, particularly in occupational settings, is largely unknown.

Triggers for genomic rearrangements: insights into genomic, cellular and environmental influences

Genomic rearrangements are associated with many human genomic disorders, including cancers. It was previously thought that most genomic rearrangements formed randomly but emerging data suggest that many are nonrandom, cell type-, cell stage- and locus-specific events. Recent studies have revealed novel cellular mechanisms and environmental cues that influence genomic rearrangements. In this Review, we consider the multitude of influences on genomic rearrangements by grouping these influences into four categories: proximity of chromosomal regions in the nucleus, cellular stress, inappropriate DNA repair or recombination, and DNA sequence and chromatin features. The synergy of these triggers can poise a cell for rearrangements and here we aim to provide a conceptual framework for understanding the genesis of genomic rearrangements.

Abnormal fatty acid distribution of the serum phospholipids of patients with non-Hodgkin lymphoma

The data about the fatty acid (FA) status of non-Hodgkin lymphoma (NHL) patients are poor. Therefore, the aim of this study was to investigate the FA profile of serum phospholipids in NHL patients related to the aggressiveness and clinical stage of NHL. We analyzed the FA profile of serum phospholipids in 47 newly diagnosed, untreated NHL patients and in 29 healthy subjects. Significantly higher (p < 0.001) levels of palmitic (16:0), oleic (18:1 n-9) and arachidonic acids (20:4 n-6), saturated and monounsaturated FA were found in NHL patients, while linoleic acid (18:2 n-6) and the levels of total polyunsaturated FA (PUFA), n-3 PUFA, eicosapentaenoic (20:5 n-3) and docosahexaenoic (DHA, 22:6 n-3) were significantly reduced (p < 0.01). The level of oleic acid in patients with indolent NHL was significantly lower (p < 0.05) than in more aggressive types of disease. Contents of palmitoleic acid, docosatetraenoic (22:4 n-6), and PUFA was lower in very aggressive NHL. According to clinical stage (CS), patients with CS I had significantly higher SFA and lower n-6 FA than other three groups, and group with CS IV showed significantly decreased DHA and n-3 PUFA. Our results showed an abnormal FA profile in serum phospholipids in NHL patients.

Msh2-dependent DNA repair mitigates a unique susceptibility of B cell progenitors to c-Myc-induced lymphomas

C-Myc is one of the most common targets of genetic alterations in human cancers. Although overexpression of c-Myc in the B cell compartment predisposes to lymphomas, secondary mutations are required for disease manifestation. In this article, we show that genetic deficiencies causing arrested B cell development and accumulation of B cell progenitors lead to accelerated lymphomagenesis in Emu c-myc transgenic mice. This result suggests that B cell progenitors are more prone than their mature counterparts to developing secondary oncogenic lesions that complement c-Myc in promoting transformation. To investigate the nature of these oncogenic lesions, we examined Emu c-myc mice deficient in mismatch repair function. We report that Msh2(-/-) Emu c-myc and Msh2(G674A/G674A) Emu c-myc mice rapidly succumb to pro-B cell stage lymphomas, indicating that Msh2-dependent mismatch repair function actively suppresses c-Myc-associated oncogenesis during early B cell development.

Real-time quantitative PCR using hairpin-shaped clone-specific primers for minimal residual disease assessment in an animal model of human non-Hodgkin lymphoma

A multitude of molecular techniques for monitoring minimal residual disease in lymphoproliferative disorders have been described to date. Real-Time Quantitative PCR targeting Immunoglobulin Heavy chain patient-specific sequences is increasingly being used for molecular detection of residual neoplastic B-cells using allele-specific oligos. The establishment of individually tailored PCR assays with the extensive use of patient-specific fluorescent-labeled oligos may be cumbersome and expensive. The present study was aimed at evaluating the usefulness of recently described hairpin-shaped allele-specific primers, originally intended for typing single-nucleotide polymorphisms, for the assessment of minimal residual disease using SYBR Green intercalating dye. Three cloned and 2 sequenced clonogenic Ig heavy chain rearranged gene loci, obtained from 5 cases of canine spontaneous B-cell lymphoma, were used as an experimental model. Both standard linear and hairpin-shaped forward and reverse clone-specific primers were evaluated in terms of specificity, sensitivity and PCR efficiency. Hairpin-shaped primers were demonstrated to have achieved accurate results more consistently than the respective linear primers allowing the specific and sensitive quantification of minimal residual disease of lymphoproliferative disorders with fewer validation procedures and more flexibility on the assay design.

Potent in vitro and in vivo activity of an Fc-engineered anti-CD19 monoclonal antibody against lymphoma and leukemia

CD19 is a pan B-cell surface receptor expressed from pro-B-cell development until its down-regulation during terminal differentiation into plasma cells. CD19 represents an attractive immunotherapy target for cancers of lymphoid origin due to its high expression levels on the vast majority of non-Hodgkin's lymphomas and some leukemias. A humanized anti-CD19 antibody with an engineered Fc domain (XmAb5574) was generated to increase binding to Fcgamma receptors on immune cells and thus increase Fc-mediated effector functions. In vitro, XmAb5574 enhanced antibody-dependent cell-mediated cytotoxicity 100-fold to 1,000-fold relative to an anti-CD19 IgG1 analogue against a broad range of B-lymphoma and leukemia cell lines. Furthermore, XmAb5574 conferred antibody-dependent cell-mediated cytotoxicity against patient-derived acute lymphoblastic leukemia and mantle cell lymphoma cells, whereas the IgG1 analogue was inactive. XmAb5574 also increased antibody-dependent cellular phagocytosis and apoptosis. In vivo, XmAb5574 significantly inhibited lymphoma growth in prophylactic and established mouse xenograft models, and showed more potent antitumor activity than its IgG1 analogue. Comparisons with a variant incapable of Fcgamma receptor binding showed that engagement of these receptors is critical for optimal antitumor efficacy. These results suggest that XmAb5574 exhibits potent tumor cytotoxicity via direct and indirect effector functions and thus warrants clinical evaluation as an immunotherapeutic for CD19(+) hematologic malignancies.

GeneScanning analysis of Ig/TCR gene rearrangements to detect clonality in canine lymphomas

The diagnosis of canine lymphoma is achieved using morphological and immunological methods. In a certain percentage of cases, difficulties in making a definitive diagnosis of lymphoproliferative disorders may occur despite extensive immunophenotyping. Therefore, additional diagnostics, such as molecular assessment of Ig/TCR gene rearrangements clonality, may confirm the final diagnosis. Polyacrylamide gel electrophoresis and heteroduplex analysis have already been proven to be suitable for detecting clonality but are cumbersome and labor-intensive. In the present study, GeneScanning analysis of PCR products originating from different primer sets targeting different regions of Ig and TCR was validated in improving sensitivity as well as in reducing the turnaround time of gene rearrangement assays. GeneScanning exploits 5' fluorescently labelled primers for the automated and fast analysis of PCR products either as singleplex or multiplex runs. Initially, the assay was set up using DNA purified from normal tissues (n=6), hyperplastic/reactive tissues (n=10) and a small set of immunophenotyped lymphoma samples (n=12). The optimized methods were then used in a large set of 96 canine lymphoma samples. Normal and hyperplastic/reactive lymphoid tissues showed typically polyclonal or, occasionally, oligoclonal PCR products. Lymphoma samples showed monoclonal peaks arranged as a single or, occasionally, a double narrow base peak sometimes embedded in a polyclonal background. In all immunophenotyped cases, an Ig or TCR clonal finding corresponded to B- and T-cell lymphomas, respectively. Overall, 94/96 (97.9%) samples showed clonal Ig/TCR clonal rearrangements among which clonal Ig was found in 61/96 (63.5%) of samples and clonal TCR in 33/35 Ig negative samples (34.4% of all cases). In one out of ten randomly chosen cases, both Ig and TCR clonal gene rearrangements were found. Among the factors affecting assay accuracy, DNA quality has been shown to be critical and the amplification of DNA controls of different size are recommended to evaluate DNA integrity. Frozen material such as that which remained inside the hub of the needle used for diagnostic procedures is optimal for the analysis herein described. In conclusion, GeneScanning represents a versatile tool for routinely assessing Ig/TCR clonal rearrangements and supporting the diagnostic protocol of canine lymphomas.

Nuclear microenvironment in cancer diagnosis and treatment

The nuclear architecture plays an important role in the temporal and spatial control of complex functional processes within the nucleus. Alterations in nuclear structures are characteristic of cancer cells and the mechanisms underlying these perturbations may directly contribute to tumor development and progression. In this review, we will highlight aspects of the nuclear microenvironment that are perturbed during tumorigenesis and discuss how a greater understanding of the role of nuclear structure in the control of gene expression can provide new options for cancer diagnosis and treatment.

Oral Hodgkin lymphoma: a wolf in wolf's clothing

Hodgkin lymphoma typically presents as a nodal lesion and infrequently involves extranodal sites. The English language literature contains only 7 reports of primary Hodgkin lymphoma arising in the oral mucosa in the absence of nodal disease. We report a case of primary, extranodal Hodgkin lymphoma in the palatal mucosa of a 79-year-old white female. An incisional biopsy revealed a diffuse, mixed cellular infiltrate, consisting of benign lymphocytes, plasma cells, histiocytes, and foci rich in eosinophils. Within this background was a scattering of large, atypical cells, including Reed-Sternberg forms that exhibited immunoreactivity for CD30 and CD20 and nonreactivity for CD15 and CD45RO, supporting a diagnosis of classical Hodgkin lymphoma. Positron emission tomography exhibited a single focal area of abnormal hypermetabolic activity involving the left palate area, without involvement of any other site. The clinical stage was Ann Arbor I-A. The primary tumor and submandibular and upper neck lymph nodes were treated with a 6-MV photon beam to a total dose of 4000 cGy. There was no evidence of disease at 15-month follow-up.

Intraocular lymphoma: update on diagnosis and management

BACKGROUND

Primary intraocular lymphoma (PIOL) is a subset of primary central nervous system lymphoma (PCNSL) in which lymphoma cells initially invade the retina, vitreous, or optic nerve head, with or without concomitant CNS involvement. The incidence of this previously rare condition has increased dramatically. Given its nonspecific presentation and aggressive course, PIOL provides a diagnostic and therapeutic challenge.

METHODS

We review the current strategies for diagnosis and treatment of PIOL and present our own experience with PIOL.

RESULTS

Recent developments in the diagnosis of PIOL include immunohistochemistry, flow cytometry, cytokine evaluation, and molecular analysis. However, definitive diagnosis still requires harvesting of tissue for histopathology. Optimal treatment for PIOL remains unclear. Initial therapeutic regimens should include methotrexate-based chemotherapy and radiotherapy to the brain and eye. In addition, promising results have been seen with intravitreal methotrexate and autologous stem cell transplantation for recurrent and refractory disease.

CONCLUSIONS

Efforts to further determine the immunophenotype and molecular characteristics of PIOL will continue to assist in the diagnosis of PIOL. Future studies are required to determine the role of radiotherapy and optimal local and systemic chemotherapeutic regimens.

Hepatitis C and risk of lymphoma: results of the European multicenter case-control study EPILYMPH

BACKGROUND & AIMS

Increasing evidence points toward a role of hepatitis C virus (HCV) infection in the etiology of malignant lymphomas. However, previous epidemiologic studies were limited in size to establish an association between HCV infection and specific lymphoma subtypes. We performed a large, multicenter, case-control study to address this question.

METHODS

The study comprised 5 European countries and included newly diagnosed cases of any lymphoid malignancy recruited between 1998 and 2004. Controls were matched to cases by 5-year age group, sex, and study center. In-person interviews were conducted to collect data on demographic, medical, and family history as well as environmental exposures. Serum samples of 1807 cases and 1788 controls (excluding human immunodeficiency virus-positive and organ-transplantation subjects) were screened for HCV infection using an enzyme immunoassay. Positive as well as randomly selected negative samples were subjected to HCV RNA detection and HCV genotyping.

RESULTS

HCV infection was detected in 53 (2.9%) lymphoma cases and in 41 (2.3%) control subjects (odds ratio [OR], 1.42; 95% confidence interval [CI]: 0.93-2.15). Restricted to individuals who tested positive for HCV-RNA (indicating persistent infection and active viral replication), the OR was 1.82 (95% CI: 1.13-2.91). In subtype-specific analyses, HCV prevalence was associated with diffuse large B-cell lymphoma (OR, 2.19; 95% CI: 1.23-3.91) but not with chronic lymphocytic leukemia or follicular, Hodgkin's, or T-cell lymphoma. The sample size was not sufficient to derive any conclusions for rare lymphoma entities such as splenic marginal zone lymphoma.

CONCLUSIONS

These results support a model that chronic HCV replication contributes to lymphomagenesis and establish a specific role of HCV infection in the pathogenesis of diffuse large B-cell lymphoma.

Pathology of primary central nervous system lymphoma

✓ The understanding of primary central nervous system lymphoma (PCNSL) has lagged behind that of the much more common systemic, nodal lymphomas. Reasons for this include the relative rarity of PCNSL and the fact that these lesions differ in some ways from their histologically similar systemic counterparts. The purpose of this paper is twofold: first, the author provides concise descriptions of the pathological features of both common and uncommon types of PCNSL while discussing issues such as the confusion surrounding histological classification of PCNSLs, problems related to intraoperative diagnosis, and the appropriate diagnostic work up. Second, the author discusses a small number of molecular studies to demonstrate the great promise they offer. Such studies have already clarified some issues, including the category of lymphocyte from which the majority of PCNSLs are derived. Hopefully in the future these studies will help guide treatment decisions.

Gene polymorphisms in Toll-like receptors, interleukin-10, and interleukin-10 receptor alpha and lymphoma risk

Interactions between environment and immune system play an essential role in the aetiology of immunopathologies, including lymphomas. Toll-like receptors (TLR) belong to a group of pattern recognition receptors, with importance for innate immune response and inflammatory processes. Interleukin-10 (IL-10) is a key regulatory cytokine and has been implicated in lymphomagenesis. Functional polymorphisms in these inflammation-associated genes may affect the susceptibility towards lymphoma. To test this hypothesis, we have genotyped DNA of 710 lymphoma cases and 710 controls within the context of a population-based epidemiological study for 11 functionally important single-nucleotide polymorphisms in TLR1, -2, -4, -5, -9, IL10 and IL10 receptor (IL10RA). The IL10RA Ser138Gly variant was underrepresented among lymphoma cases (odds ratio (OR)=0.81, 95 per cent confidence interval (95% CI)=0.65-1.02), mainly owing to an inverse association with Hodgkin's lymphoma (HL). The TLR2 -16933T>A variant was associated with a 2.8-fold increased risk of follicular lymphoma (95% CI=1.43-5.59) and a decreased risk of chronic lymphocytic leukaemia (OR=0.61, 95% CI=0.38-0.95). Furthermore, the TLR4 Asp299Gly variant was positively associated with the risk of mucosa-associated lymphoid tissue lymphoma (OR=2.76, 95% CI=1.12-6.81) and HL (OR=1.80, 95% CI=0.99-3.26). In conclusion, this study suggests an effect of polymorphisms in factors of the innate immune response in the aetiology of some lymphoma subtypes.

[Significance of the initial cytomorphological and immunocytochemical findings and the correlation with the International Prognostic Index for the survival in patients with non-Hodgkin's lymphoma]

BACKGROUND/AIM

Fine-needle aspiration biopsy is a quick, economical, and safe initial method in managing a patient with suspected lymphoma. According to a few reports on this preoblem, the aim of this study was to compare histological findings to cytomorphological ones in needle aspirates. We also compared these findings to the overal survival (OS) time.

METHODS

We analyzed the fine-needle aspiration biopsies of peripheral lymph nodes, and the International Prognostic Index (IPI) in 81 patients with non-Hodgkin's lymphoma (NHL). We put these findings into correlation with OS time.

RESULTS

According to the International Working Formulation (IWF) criteria, the dominant cell population was asfollows: 18 patients had the small cell population, 21 patients had small cleaved cells, 18 patients had the mixed cell population, 21 patients had large cell population, 2 patients had Burkitt lymphoma type, and 1 patient had the dominant lymphoblasts. On presentation, 32 patients had a low IPI index, 32 patients had a low intermediate, and 17 patients had a high intermediate IPI. We confirmed the statistical significance (Kaplan-Mayer) of cytomorphology (p = 0.013) and IPI index (p = 0.016) for survival time. During a 48-month follow-up, OS was 37.2 months for the patients with the dominant small cells, and 32 months for the patients with small cleaved cells (PH equivalent to indolent NHL). For the patients with the dominant mixed cell population, large cell population and Burkitt limphoma cell, OS were 17, 14.4, and 9.3 months, respectively (PH equivalent to aggressive NHL). Patients with low IPI had the highest OS, 36 months for the low intermediate and only 11.6 months for the high intermediate IPI index.

CONCLUSION

We concluded that an initial cytological and clinical profile of patients with NHL, might give a quick and relevant information for planning an adequate therapy.

Grading follicular lymphoma on fine-needle aspiration specimens-A practical approach

Fine-needle aspiration biopsy (FNA) is a useful tool for evaluating and staging follicular lymphoma (FL) without subjecting patients to multiple excisional biopsies. The relative lack of architecture in FNA is a limitation in grading FL. Recognizing the various cellular components in aspirates of FL, correlating with flow cytometry, using other ancillary tests, and preparing cell blocks can help overcome difficulties in the grading process. Understanding the clinical relevance of distinguishing the various grades of FL is important in determining whether an aspiration biopsy is adequate or whether additional sampling by surgical biopsy is indicated.

B-cell lymphomas differ in their responsiveness to CpG oligodeoxynucleotides

Human B cells detect CpG motifs within microbial DNA via TLR9. Synthetic CpG oligodeoxynucleotides are currently being tested in clinical trials for the therapy of different types of B cell non-Hodgkin's lymphoma. However, there is only limited information on the CpG oligodeoxynucleotide sensitivity of primary malignant B cells of different non-Hodgkin's lymphoma entities. Here we found that most B-cell malignancies except plasmacytoma respond to CpG oligodeoxynucleotides by up-regulating expression of costimulatory and antigen-presenting molecules, by increasing expression of CD20, and by proliferation. In an in vitro analysis of 41 individual patient-derived primary tumor samples, B-cell chronic lymphocytic leukemia (B-CLL) and marginal zone lymphoma showed the strongest activation upon stimulation with CpG oligodeoxynucleotides. Small lymphocytic lymphoma, follicular lymphoma, mantle cell lymphoma, and large cell lymphoma showed an intermediate response. Consistent with CpG oligodeoxynucleotides sensitivity, TLR9 mRNA was present in B-CLL but absent in plasmacytoma. Although CpG oligodeoxynucleotides induced proliferation in all CpG oligodeoxynucleotide-sensitive types of B-cell malignancies, proliferation was weaker than in normal B cells and at least for B-CLL was followed by increased apoptosis. In conclusion, B-cell malignancies show significant differences in their responsiveness to CpG oligodeoxynucleotides. Focusing clinical studies on patients with highly CpG oligodeoxynucleotide-sensitive B-cell malignancies may improve the clinical outcome of such trials.

Frequent aberrations of chromosome 8 in aggressive B-cell non-Hodgkin lymphoma

Translocations involving chromosome 8 are the most common aberrations in B-cell non-Hodgkin lymphoma (B-NHL). The presence of the typical t(8;14)(q24;q32) or its variants has been confirmed in all cases of Burkitt lymphoma (BL), in some cases of Burkitt-like lymphoma (BLL), and in diffuse large B-cell lymphoma (DLBCL). The alterations lead to deregulated expression of c-myc protein by a chromosomal translocation joining C-MYC gene with sequences from immunoglobulin (Ig) enhancers. The C-MYC gene rearrangement plays an essential role in leukemogenesis of BL and probably plays a part in other aggressive NHLs. The present study was undertaken to compare the cytogenetic features in cases of BL, BLL, and DLBCL. We detected chromosomal aberrations by G-banding and fluorescence in situ hybridization (FISH) painting in 10 cases of aggressive B-NHL and used FISH to visualize the C-MYC gene rearrangement. Chromosome 8 was most frequently involved in structural aberrations (8/10 cases), and 4 cases showed the typical t(8;14)(q24;q32). Only two of 5 patients suspected of having BL fulfilled all the criteria for this diagnosis; in the others, chromosome 8 was aberrant, but the absence of C-MYC rearrangement or the results of flow cytometry excluded the diagnosis of BL. All BLL cases showed C-MYC overexpression, but only one had a rearrangement of the C-MYC gene; the remaining cases showed other aberrations of chromosome 8. This study indicates that the mechanisms of C-MYC activation involved in BLL can be different from that for the BL.

Early TCR-beta and TCR-gamma PCR detection of T-cell clonality indicates minimal tumor disease in lymph nodes of cutaneous T-cell lymphoma: diagnostic and prognostic implications

The lymph nodes are generally the first extracutaneous manifestation in patients with cutaneous T-cell lymphoma (CTCL); however, their early involvement is difficult to assess. The aim of our study was to define the diagnostic and prognostic value of T-cell clonality analysis for a more precise assessment of lymph node involvement in CTCL. T-cell clonality was determined by 2 independent polymerase chain reaction (PCR) assays, namely a recently developed T-cell receptor-beta (TCR-beta) PCR technique as well as an established TCR-gamma PCR. T-cell clonality was found in 22 of 22 lymph nodes with histologically detectable CTCL involvement as well as in 7 of 14 histologically noninvolved dermatopathic lymph nodes. The clonal T-cell populations in the lymph nodes were in all cases identical to those detected in the corresponding skin lesions, identifying them as the tumor cell population. T-cell clonality was not found in any of the 12 dermatopathic lymph nodes from 12 patients with inflammatory skin diseases. Clonal T-cell detection in 7 of 14 dermatopathic lymph nodes of patients with CTCL was associated with limited survival (74 months; confidence interval [CI], 66-82 months) as in patients with histologically confirmed lymph node involvement (41 months; CI, 35-47 months), whereas all patients without T-cell clonality in the lymph nodes (7 patients) were alive at the last follow-up. Thus, T-cell clonality analysis is an important adjunct in differentiating benign dermatopathic lymphadenitis from early CTCL involvement.

The nature and origin of the B-chronic lymphocytic leukemia cell: a tentative model

Chronic lymphocytic leukemia cells have the profile of antigen (Ag) activated memory B cells but also show a constellation of T-cell-associated properties. We suggest that the early transforming events may occur in an early lymphoid progenitor. This precursor differentiates into a mature B cell that, though retaining T-cell features, has a functional B-cell receptor that may allow Ag intervention to trigger clonal expansion. This model has to cope with the existence of at least two subsets of the disease as defined by their IgVH genes mutational status. Mutated cases have a lower capacity to interact with Ag and are reminiscent of anergic cells. This explains their less harmful behavior as compared with unmutated case, which have a more aggressive potential likely because they had the opportunity to acquire additional chromosomal aberrations after repeated rounds of Ag stimulation and replication.

Classification of B-cells according to their differentiation status, their micro-anatomical localisation and their developmental lineage

B-lymphocytes or B-cells form a diverse and flexible repertoire of immune cells that are reactive to almost all potential pathogens by means of the production of antigen-specific immunoglobulins. They can be divided into different populations or subsets, characterised by a distinct combination of properties. These subsets are identified on the base of their differentiation status (precursor B-cells, peripheral B-cells), their localisation in the micro-anatomical compartments of the B-cell follicle (marginal zone B-cells, lymphocytic corona B-cells, follicle centre B-cells), and the developmental lineage to which they belong (B-1 cells, and B-2 or conventional B-cells). The latter classification of B-cells into B-1 cells and B-2 cells is commonly followed by immunologists, mainly in the study of mice models, while pathologists and haematologists tend to use a terminology for B-cells which refers to their localisation in the micro-anatomical compartments of the B-cell follicle and/or differentiation status. In this review, we will discuss the various subsets of B-cells and point to the similarities between the various classification systems in use.

Molecular heterogeneity of diffuse large B-cell lymphoma: implications for disease management and prognosis

Diffuse large B-cell lymphoma (DLBCL) accounts for approximately 40% of all B-cell non-Hodgkin lymphomas of the Western world. According to the "WHO classification of tumours of the haematopoietic and lymphoid tissues", the term DLBCL is likely to include more than one disease entity, as suggested by the marked variability of the clinical presentation and response to treatment of this disease. Such heterogeneity may reflect the occurrence of distinct molecular subtypes of DLBCL as well as differences in the host's immune function. In immunocompetent hosts, approximately 50% DLBCL carry one of two primary molecular lesions defining two distinct genotypic subgroups, characterized by activation of either the BCL-6 or the BCL-2 proto-oncogene. Conversely, the remaining DLBCL of immunocompetent hosts display one of several molecular lesions, each associated with a small subset of cases and including activation of the proto-oncogenes REL, MUC-1, BCL-8 and c-MYC. The molecular pathogenesis of immunodeficiency-associated DLBCL differs substantially from that of DLBCL in immunocompetent hosts. In fact, EBV infection is present in a large fraction of immunodeficiency-associated DLBCL, whereas it is consistently negative in DLBCL of immunocompetent hosts, probably reflecting the critical role of disruption of the immune system in this disease. Finally, the application of DNA microarray technology to DLBCL has led to the distinction of two disease variants: a germinal center like DLBCL and an activated peripheral B-cell like DLBCL. Overall the molecular features of DLBCL may identify prognostic categories of the disease and may represent a powerful tool for therapeutic stratification.

Identification of nucleolin as an AU-rich element binding protein involved in bcl-2 mRNA stabilization

bcl-2 mRNA contains an AU-rich element (ARE) that functions in regulating bcl-2 stability. Our earlier studies indicated that taxol- or okadaic acid-induced bcl-2 mRNA destabilization in HL-60 cells is associated with decreased binding of trans-acting factors to the ARE. To identify factors that play a role in the regulation of bcl-2 mRNA stability, bcl-2 ARE-binding proteins were purified from HL-60 cells. Three polypeptides of 100, 70, and 32 kDa were isolated from a bcl-2 ARE affinity matrix. Matrix-assisted laser desorption ionization mass spectroscopy analysis identified these proteins as full-length nucleolin and proteolytic fragments of nucleolin. RNA gel shifts assays indicated that recombinant nucleolin (residues 284-707) binds specifically to bcl-2 ARE RNA. In addition, recombinant nucleolin decreases the rate of decay of mRNA in HL-60 cell extracts in an ARE-dependent manner. Taxol or okadaic acid treatment of HL-60 cells results in proteolysis of nucleolin in a similar time frame as drug-induced bcl-2 mRNA down-regulation. These findings suggest that nucleolin functions as a bcl-2-stabilizing factor and that taxol and okadaic acid treatment induces apoptosis in HL-60 cells through a process that involves down-regulation of nucleolin and destabilization of bcl-2 mRNA.

A low-density cDNA microarray with a unique reference RNA: pattern recognition analysis for IFN efficacy prediction to HCV as a model

We have designed and established a low-density (295 genes) cDNA microarray for the prediction of IFN efficacy in hepatitis C patients. To obtain a precise and consistent microarray data, we collected a data set from three spots for each gene (mRNA) and using three different scanning conditions. We also established an artificial reference RNA representing pseudo-inflammatory conditions from established hepatocyte cell lines supplemented with synthetic RNAs to 48 inflammatory genes. We also developed a novel algorithm that replaces the standard hierarchical-clustering method and allows handling of the large data set with ease. This algorithm utilizes a standard space database (SSDB) as a key scale to calculate the Mahalanobis distance (MD) from the center of gravity in the SSDB. We further utilized sMD (divided by parameter k: MD/k) to reduce MD number as a predictive value. The efficacy prediction of conventional IFN mono-therapy was 100% for non-responder (NR) vs. transient responder (TR)/sustained responder (SR) (P < 0.0005). Finally, we show that this method is acceptable for clinical application.

Prognostic value of cell-cycle markers in ocular adnexal lymphoma: an assessment of 230 cases

BACKGROUND

To determine the prognostic value of cell-cycle associated markers in ocular adnexal lymphoma (OAL).

METHODS

Two hundred sixty-one consecutive cases of ocular adnexal lymphoproliferative lesions were subdivided into reactive lymphoid hyperplasia (RLH), atypical lymphoid hyperplasia (ALH) and OAL. The latter were sub-typed according to the new WHO Lymphoma Classification. All lesions were investigated applying standard immunohistochemical methods with antibodies specific for pRB, p53, p16, p21, BCL-6 and for multiple myeloma oncogene-1-protein (MUM1, also known as IRF4). The main endpoints included the development of a local recurrence, of systemic disease and of lymphoma-related death. The association of prognostic variables with endpoints was assessed by multiple logistic and Cox regression models, respectively.

RESULTS

The ocular adnexal lymphoproliferative lesions were categorised as OAL ( n=230; 88%), RLH ( n=29; 11%), and ALH ( n=2; 1%). The major lymphoma subtypes included 136 extranodal marginal zone B-cell lymphoma (EMZL), 31 diffuse large cell B-cell lymphomas, 27 follicular lymphomas, 9 plasmacytomas, 9 lymphoplasmocytic lymphoma/immunocytomas and 8 mantle cell lymphomas. The median follow-up time was 44.5 months. Most OAL patients had Stage IE disease and were treated with radiotherapy. Thirty-seven (25%) Stage IE patients had tumour relapses: these were significantly associated with an increased BCL6 blast percentage. Sixty-two (42%) Stage IE patients developed systemic disease: they had "non-EMZL" with large growth fractions and increased blast percentages for BCL6. Fifty-seven (25%) OAL patients died because of their lymphoma; lymphoma-related death was significantly associated on multivariable analysis with advanced clinical stage, an age >60 years and large tumour growth fractions.

CONCLUSION

Subtyping of OAL according to the new WHO Lymphoma Classification, the stage of disease and tumour cell growth fraction aided the prediction of (1) tumour relapse, (2) the development of systemic disease and (3) lymphoma-related death in OAL.

Evaluation of vitrectomy specimens and chorioretinal biopsies in the diagnosis of primary intraocular lymphoma in patients with Masquerade syndrome

PURPOSE

To correlate the histopathological diagnoses established by diagnostic vitrectomy and chorioretinal biopsy in patients with clinically suspected primary intraocular lymphoma (PIOL) or chronic idiopathic uveitis, and the clinical follow-up data.

METHODS

Eighty-four consecutive pars plana vitrectomy (PPV) specimens, three chorioretinal biopsies and two enucleated eyes taken from 80 patients were evaluated. All PPV specimens were unfixed; these were centrifuged, the "cytospins" being stained conventionally (May-Grünwald-Giemsa) and using immunocytology (CD79a, CD3, CD68, immunoglobulin (Ig) light chains). An extended immunohistochemical panel, as well as polymerase chain reaction (PCR) for rearrangements of the Ig heavy chain gene (IgH-PCR), were used to investigate the chorioretinal biopsies and the enucleated eyes. Diagnoses, made on the basis of morphology and immunophenotype, included "reactive cellular infiltrate", "malignant lymphoma", "suspicious of neoplastic disease", and "insufficient for diagnosis". The corresponding clinical data were collected and compared with the diagnosis.

RESULTS

The 80 patients consisted of 46 women and 34 men. The patients' age range varied from 21 to 100 years (mean age 62 years). Sixty-two (74%) of the 84 vitrectomy specimens were diagnosed as "reactive cellular infiltrate", 12 (14%) as definite "malignant lymphoma", 5 (6%) as "suspicious of neoplastic disease" and 5 (6%) specimens were considered "insufficient for diagnosis". An additional chorioretinal biopsy enabled an unequivocal diagnosis of PIOL to be reached in 3 patients. All PIOL were diffuse large cell B-cell lymphoma (DLBCL), with the immunophenotype CD79+, CD20+, BCL-2+, BCL-6+, MUM1+ and monotypical expression for IgM+. A monoclonal IgH-PCR amplification product was obtained in four vitrectomy specimens, two chorioretinal biopsies and one of the enucleated eyes. Comparison of the diagnoses with long-term follow-up clinical data resulted in concordance in 77 (96%) cases and discrepancies ("false-negative" diagnoses) in 3 patients (4%). The patients diagnosed with lymphoma were treated with either radiotherapy, chemotherapy or both. At final follow-up (mean 35 months), 5 patients (6%) had developed cerebral lymphomatous manifestation, and 7 (9%) had succumbed to their disease.

CONCLUSION

The diagnosis of PIOL is often extremely difficult, requiring sufficient rapidly transported good-quality material, and experienced interpretation. Although cytological examination of vitreal aspirates remains the gold standard in diagnosis, examination of chorioretinal biopsies increase the reliability of diagnosing or excluding a PIOL that involves the retina or choroid. Most PIOL are DLBCL with an immunophenotype suggesting a cellular origin from germinal centre cells.

Non-Hodgkin lymphoma

Non-Hodgkin lymphoma is a non-specific term that includes several lymphoproliferative malignant diseases with different clinical and histological appearances. Here, we concentrate on adult lymphomas. We look at their molecular basis, at the development of a classification system based on a better understanding of the biology of the various subgroups, and at how refinement of adverse prognostic factor groupings helps in clinical management. Lymphomas can present in various ways and be difficult to diagnose. About a quarter of cases arise extranodally and might present special problems. Developments in cytotoxic chemotherapy have led to good long-term survival prospects for aggressive lymphoma; introduction of novel approaches, including monoclonal antibody therapy, offers promise for indolent lymphoma, and should further improve prognosis for aggressive tumours.