Cytogenetic abnormalities additional to t(11;14) correlate with clinical features in leukaemic presentation of mantle cell lymphoma, and may influence prognosis: a study of 60 cases by FISH

Plasmablastic Lymphoma. A State-of-the-Art Review: Part 2-Focus on Therapy

The objective of this two-part review is to present a current and comprehensive understanding of the diagnosis and management of plasmablastic lymphoma. The first part, which was published previously, focused on the study of epidemiology, etiology, clinicopathological characteristics, differential diagnosis, prognostic variables, and the impact of plasmablastic lymphoma on specific populations. This second part addresses the difficult topic of the treatment of plasmablastic lymphoma, specifically examining both the conventional, consolidated approach and the novel therapeutic strategy.

Comprehensive FISH testing using FFPE tissue microarray of primary lymph node tissue identifies secondary cytogenetic abnormalities in Mantle Cell Lymphoma

INTRODUCTION

Mantle Cell Lymphoma (MCL), is characterised by the reciprocal translocation t(11;14) resulting in CCND1-IGH gene fusion and subsequent upregulation of the CCND1 gene. Rearrangements of MYC and losses of CDKN2A and TP53 have been identified as biomarkers informing prognostic and potentially therapeutic information however these are not routinely assessed in MCL investigation. We aimed to identify additional cytogenetic changes using fluorescence in situ hybridisation (FISH) on formalin fixed paraffin embedded (FFPE) primary lymph node tissue microarrays in a cohort of 28 patients diagnosed with MCL between 2004 and 2019. FISH results were compared with corresponding immunohistochemistry (IHC) biomarkers to determine if IHC was a reliable screening tool to direct FISH testing.

METHOD

FFPE lymph node tissue samples were constructed into tissue microarrays (TMA) which were stained with 7 immunohistochemical biomarkers: Cyclin D1, c-Myc, p16, ATM, p53, Bcl-6 and Bcl-2. The same TMAs were hybridised with FISH probes for the corresponding genes; CCND1-IGH, MYC, CDKN2A, ATM, TP53, BCL6 and BCL2. FISH and the corresponding IHC biomarkers were analysed to determine if secondary cytogenetic changes could be identified and if IHC could be used as a reliable, inexpensive predictor of FISH abnormalities to potentially direct FISH testing.

RESULTS

CCND1-IGH fusion was detected in 27/28 (96%) of samples. Additional cytogenetic changes were identified by FISH in 15/28 (54%) of samples. Two additional abnormalities were detected in 2/28 (7%) samples. Cyclin D1 IHC overexpression was an excellent predictor of CCND1-IGH fusion. MYC and ATM IHC were useful screening tests to direct FISH testing and identified cases with poor prognostic features including blastoid change. IHC did not show clear concordance with FISH for other biomarkers.

CONCLUSION

FISH using FFPE primary lymph node tissue can detect secondary cytogenetic abnormalities in patients with MCL which are associated with an inferior prognosis. An expanded FISH panel including MYC, CDKN2A, TP53 and ATM should be considered in cases where anomalous IHC expression or is seen for these markers or if the patient appears to have the blastoid variant of the disease.

Expanding anti-CD38 immunotherapy for lymphoid malignancies

BACKGROUND

Lymphoid neoplasms, including multiple myeloma (MM), non-Hodgkin lymphoma (NHL), and NK/T cell neoplasms, are a major cause of blood cancer morbidity and mortality. CD38 (cyclic ADP ribose hydrolase) is a transmembrane glycoprotein expressed on the surface of plasma cells and MM cells. The high expression of CD38 across MM and other lymphoid malignancies and its restricted expression in normal tissues make CD38 an attractive target for immunotherapy. CD38-targeting antibodies, like daratumumab, have been approved for the treatment of MM and tested against lymphoma and leukemia in multiple clinical trials.

METHODS

We generated chimeric antigen receptor (CAR) T cells targeting CD38 and tested its cytotoxicity against multiple CD38^high and CD38^low lymphoid cancer cells. We evaluated the synergistic effects of all-trans retinoic acid (ATRA) and CAR T cells or daratumumab against cancer cells and xenograft tumors.

RESULTS

CD38-CAR T cells dramatically inhibited the growth of CD38^high MM, mantle cell lymphoma (MCL), Waldenstrom's macroglobulinemia (WM), T-cell acute lymphoblastic leukemia (T-ALL), and NK/T-cell lymphoma (NKTCL) in vitro and in mouse xenografts. ATRA elevated CD38 expression in multiple CD38^low cancer cells and enhanced the anti-tumor activity of daratumumab and CD38-CAR T cells in xenograft tumors.

CONCLUSIONS

These findings may expand anti-CD38 immunotherapy to a broad spectrum of lymphoid malignancies and call for the incorporation of ATRA into daratumumab or other anti-CD38 immunological agents for cancer therapy.

Mantle cell lymphoma: insights into therapeutic targets at the preclinical level

INTRODUCTION

Mantle cell lymphoma (MCL) is a chronically relapsing B-cell non-Hodgkin lymphoma characterized by recurrent molecular-cytogenetic aberrations that lead to deregulation of DNA damage response, cell cycle progression, epigenetics, apoptosis, proliferation, and motility. In the last 10 years, clinical approval of several innovative drugs dramatically changed the landscape of treatment options in the relapsed/refractory (R/R) MCL, which translated into significantly improved survival parameters.

AREAS COVERED

Here, up-to-date knowledge on the biology of MCL together with currently approved and clinically tested frontline and salvage therapies are reviewed. In addition, novel therapeutic targets in MCL based on the scientific reports published in Pubmed are discussed.

EXPERT OPINION

Bruton tyrosine-kinase inhibitors, NFkappaB inhibitors, BCL2 inhibitors, and immunomodulary agents in combination with monoclonal antibodies and genotoxic drugs have the potential to induce long-term remissions in majority of newly diagnosed MCL patients. Several other classes of anti-tumor drugs including phosphoinositole-3-kinase, cyclin-dependent kinase or DNA damage response kinase inhibitors have demonstrated promising anti-lymphoma efficacy in R/R MCL. Most importantly, adoptive immunotherapy with genetically modified T-cells carrying chimeric antigen receptor represents a potentially curative treatment approach even in the patients with chemotherapy and ibrutinib-refractory disease.

Aggressive morphologic variants of mantle cell lymphoma characterized with high genomic instability showing frequent chromothripsis, CDKN2A/B loss, and TP53 mutations: A multi-institutional study

Aggressive morphologic variants of mantle cell lymphoma (MCL), including blastoid and pleomorphic (B/P-MCL), are rare and associated with poor clinical outcomes. The genomic landscape of these variants remains incompletely explored. In this multi-institutional study, we describe recurrent mutations and novel genomic copy number alterations (CNAs) in B/P-MCL, using next generation sequencing and SNP-array. Chromothripsis, a recently described phenomenon of massive chromosomal rearrangements, was identified in eight of 13 (62%) B/P MCL cases, and a high degree of genomic complexity with frequent copy number gains and losses was also seen. In contrast, a comparative cohort of nine cases of conventional MCL (C-MCL) showed no chromothripsis and less complexity. Twelve of 13 (92%) B/P-MCL cases showed loss of CDKN2A/B (6 biallelic and 6 monoallelic losses); while only one C-MCL showed monoallelic CDKN2A/B loss. In B/P-MCL, TP53 was the most commonly mutated gene, with mutations present in eight cases (62%), six of which showed concurrent loss of chromosome 17p. Of the eight cases with chromothripsis, six (85%) harbored TP53 mutations. Other recurrent mutations in B/P-MCL included ATM (7, 53%), CCND1 (5, 38%), NOTCH1 (2, 18%), NOTCH2, and BIRC3 (each in 3, 23%). Here, we describe high genomic instability associated with chromothripsis and a high frequency of CDKN2A/B and TP53 alterations in the aggressive variants of MCL. The nonrandom chromothripsis events observed in B/P-MCL may be an indicator of clinically aggressive MCL. In addition, frequent CDKN2A deletion and high genomic instability may provide potential targets for alternative treatment.

Advances in targeted therapy for malignant lymphoma

The incidence of lymphoma has gradually increased over previous decades, and it ranks among the ten most prevalent cancers worldwide. With the development of targeted therapeutic strategies, though a subset of lymphoma patients has become curable, the treatment of refractory and relapsed diseases remains challenging. Many efforts have been made to explore new targets and to develop corresponding therapies. In addition to novel antibodies targeting surface antigens and small molecular inhibitors targeting oncogenic signaling pathways and tumor suppressors, immune checkpoint inhibitors and chimeric antigen receptor T-cells have been rapidly developed to target the tumor microenvironment. Although these targeted agents have shown great success in treating lymphoma patients, adverse events should be noted. The selection of the most suitable candidates, optimal dosage, and effective combinations warrant further investigation. In this review, we systematically outlined the advances in targeted therapy for malignant lymphoma, providing a clinical rationale for mechanism-based lymphoma treatment in the era of precision medicine.

Ectonucleotidases in Blood Malignancies: A Tale of Surface Markers and Therapeutic Targets

Leukemia develops as the result of intrinsic features of the transformed cell, such as gene mutations and derived oncogenic signaling, and extrinsic factors, such as a tumor-friendly, immunosuppressed microenvironment, predominantly in the lymph nodes and the bone marrow. There, high extracellular levels of nucleotides, mainly NAD⁺ and ATP, are catabolized by different ectonucleotidases, which can be divided in two families according to substrate specificity: on one side those that metabolize NAD⁺, including CD38, CD157, and CD203a; on the other, those that convert ATP, namely CD39 (and other ENTPDases) and CD73. They generate products that modulate intracellular calcium levels and that activate purinergic receptors. They can also converge on adenosine generation with profound effects, both on leukemic cells, enhancing chemoresistance and homing, and on non-malignant immune cells, polarizing them toward tolerance. This review will first provide an overview of ectonucleotidases expression within the immune system, in physiological and pathological conditions. We will then focus on different hematological malignancies, discussing their role as disease markers and possibly pathogenic agents. Lastly, we will describe current efforts aimed at therapeutic targeting of this family of enzymes.

Poly(ADP-Ribose) Polymerases in Host-Pathogen Interactions, Inflammation, and Immunity

The literature review presented here details recent research involving members of the poly(ADP-ribose) polymerase (PARP) family of proteins. Among the 17 recognized members of the family, the human enzyme PARP1 is the most extensively studied, resulting in a number of known biological and metabolic roles. This review is focused on the roles played by PARP enzymes in host-pathogen interactions and in diseases with an associated inflammatory response. In mammalian cells, several PARPs have specific roles in the antiviral response; this is perhaps best illustrated by PARP13, also termed the zinc finger antiviral protein (ZAP). Plant stress responses and immunity are also regulated by poly(ADP-ribosyl)ation. PARPs promote inflammatory responses by stimulating proinflammatory signal transduction pathways that lead to the expression of cytokines and cell adhesion molecules. Hence, PARP inhibitors show promise in the treatment of inflammatory disorders and conditions with an inflammatory component, such as diabetes, arthritis, and stroke. These functions are correlated with the biophysical characteristics of PARP family enzymes. This work is important in providing a comprehensive understanding of the molecular basis of pathogenesis and host responses, as well as in the identification of inhibitors. This is important because the identification of inhibitors has been shown to be effective in arresting the progression of disease.

Complex karyotype in patients with mantle cell lymphoma predicts inferior survival and poor response to intensive induction therapy

BACKGROUND

Risk stratification of newly diagnosed patients with mantle cell lymphoma (MCL) primarily is based on the MCL International Prognostic Index (MIPI) and Ki-67 proliferative index. Single-center studies have reported inferior outcomes in patients with a complex karyotype (CK), but this remains an area of controversy.

METHODS

The authors retrospectively reviewed 483 patients from 5 academic centers in the United States and described the effect of a CK on survival outcomes in individuals with MCL.

RESULTS

A CK was found to be associated with inferior overall survival (OS) (4.5 vs 11.6 years; P<.01) and progression-free survival (PFS) (1.9 vs 4.4 years; P<.01). In patients who underwent high-intensity induction followed by autologous stem cell transplantation (ASCT) in first remission, a CK was associated with poor OS (5.1 vs 11.6 years; P = .04) and PFS (3.6 vs 7.8 years; P<.01). Among patients with a CK, high-intensity induction had no effect on OS (4.5 vs 3.8 years; P = .77) nor PFS (2.3 vs 1.5 years; P = .46). Similarly, ASCT in first remission did not improve PFS (3.5 vs 1.2 years; P = .12) nor OS (5.1 vs 4.0 years; P = .27). On multivariable analyses with Ki-67 and MIPI, only CK was found to be predictive of OS (hazard ratio [HR], 1.98; 95% confidence interval [95% CI], 1.12-3.49 [P = .02]), whereas both CK (HR, 1.91; 95% CI, 1.17-3.12 [P = .01]) and Ki-67 >30% (HR, 1.86; 95% CI, 1.06-3.28 [P = .03]) were associated with inferior PFS. Multivariable analysis did not identify any specific cytogenetic abnormalities associated with inferior survival.

CONCLUSIONS

CK appears to be independently associated with inferior outcomes in patients with MCL regardless of the intensity of induction therapy and receipt of ASCT. Cytogenetics should be incorporated into the workup of a new diagnosis of MCL and novel therapeutic approaches should be investigated for patients with CK. Cancer 2018;124:2306-15. © 2018 American Cancer Society.

Del17p does not always significantly influence the survival of B-cell chronic lymphoproliferative disorders

B-cell chronic lymphoproliferative disorders (B-CLPD) comprise several entities with indolent clinical manifestations but heterogeneous survival. Cytogenetic aberrations are now the standard prognostic predictors in chronic lymphocytic leukemia (CLL) but have been less investigated in other subtypes of B-CLPD. In this study, we detected cytogenetic aberrations by fluorescence in situ hybridization (FISH) in 875 B-CLPD patients, based on a panel probes locating at 13q14, 11q22, 17p13 and CEP12. We identified del17p acted as the independent adverse cytogenetic predictor for overall survival (OS) in CLL. Del13q, del11q and del17p were adverse factors for OS in Waldenström's macroglobulinemia in the univariate analysis but lost their role in the multivariate analysis. Trisomy 12 acted as an independent poor factor for both marginal zone lymphoma (MZL) and unclassified B-CLPD (BCLPD-U) subtype. Del17p did not impact survival in MZL and BCLPD-U patients. These contrasting results indicate different roles of the same cytogenetic aberrations in the pathogenesis of each B-CLPD subtype. As del17p contributed to the poorest survival in CLL and desired extraordinary treatment strategy, the imitation of CLL strategy to other B-CLPD with del17p should be carefully advocated based on this study.

Bone marrow micro-environment is a crucial player for myelomagenesis and disease progression

Despite the advent of many therapeutic agents, such as bortezomib and lenalidomide that have significantly improved the overall survival, multiple myeloma remains an incurable disease. Failure to cure is multifactorial and can be attributed to the underlying genetic heterogeneity of the cancer and to the surrounding micro-environment. Understanding the mutual interaction between myeloma cells and micro-environment may lead to the development of novel treatment strategies able to eradicate this disease. In this review we discuss the principal molecules involved in the micro-environment network in multiple myeloma and the currently available therapies targeting them.

Monoclonal antibodies targeting CD38 in hematological malignancies and beyond

CD38 is a multifunctional cell surface protein that has receptor as well as enzyme functions. The protein is generally expressed at low levels on various hematological and solid tissues, while plasma cells express particularly high levels of CD38. The protein is also expressed in a subset of hematological tumors, and shows especially broad and high expression levels in plasma cell tumors such as multiple myeloma (MM). Together, this triggered the development of various therapeutic CD38 antibodies, including daratumumab, isatuximab, and MOR202. Daratumumab binds a unique CD38 epitope and showed strong anti-tumor activity in preclinical models. The antibody engages diverse mechanisms of action, including complement-dependent cytotoxicity, antibody-dependent cellular cytotoxicity, antibody-dependent cellular phagocytosis, programmed cell death, modulation of enzymatic activity, and immunomodulatory activity. CD38-targeting antibodies have a favorable toxicity profile in patients, and early clinical data show a marked activity in MM, while studies in other hematological malignancies are ongoing. Daratumumab has single agent activity and a limited toxicity profile, allowing favorable combination therapies with existing as well as emerging therapies, which are currently evaluated in the clinic. Finally, CD38 antibodies may have a role in the treatment of diseases beyond hematological malignancies, including solid tumors and antibody-mediated autoimmune diseases.

High incidence of MYC and BCL2 abnormalities in mantle cell lymphoma, although only MYC abnormality predicts poor survival

The incidence and prognostic role of MYC and BCL2 rearrangements in mature B-cell lymphomas have been extensively studied, except the infrequent mantle cell lymphoma (MCL). Here, we analyzed the MYC and BCL2 abnormalities and other cytogenetic aberrations by fluorescence in situ hybridization (FISH) in 50 MCL patients with bone marrow involvement. Eighteen patients (36.0%) had MYC gains and/or amplifications, and twelve patients (24.0%) had BCL2 gains and/or amplifications. Among the 18 patients with MYC abnormality, four had simultaneous MYC translocations, but no BCL2 translocation was detected among patients with BCL2 abnormality. Only two patients (4.0%) had both MYC and BCL2 abnormalities. The patients with a MYC abnormality had a significantly higher tumor burden, a higher percentage of medium/high risk MIPI group and genomic instability compared to those without this abnormality. However, no significant difference was observed between patients with or without a BCL2 abnormality in terms of clinical and cytogenetic factors. Patients with a MYC abnormality had poorer progress-free survival (PFS) (9.0 vs. 48.0 months, p = .000) and overall survival (OS) (12.0 vs. 94.5 months, p = .000), but the presence of a BCL2 abnormality did not significantly influence either PFS or OS. In multivariate analysis, the MYC abnormality was the independent adverse factor for both PFS and OS, and intensive chemotherapy did not improve the outcome of these patients. Thus, the presence of a MYC but not BCL2 abnormality predicted the poor survival of MCL patients, and a new treatment strategy should be developed for these patients.

Blastoid variant mantle cell lymphoma with complex karyotype including 11q duplication

We describe a case of blastoid mantle cell lymphoma with a complex karyotype. The blastoid variant is a rare type of non-Hodgkin lymphoma exhibiting an aggressive clinical course. Mantle cell lymphoma is a distinct entity of mature B-cell neoplasms genetically characterized by the presence of t(11;14). In the present case, conventional analysis revealed structural abnormalities of chromosomes 2, 4, 6, 10, 13, and 19, along with 3 additional marker chromosomes. The derivative 1 chromosome determined in the case was a result of t(1p;11q). Our interesting finding was the presence of a different translocation between 11q and chromosome 1 in addition to t(11;14). Thus, the resulting 11q duplication was believed to additionally increase the enhanced expression of cyclin D1 gene, which is responsible in the pathogenesis of the disease. Fluorescence in situ hybridization method by the t(11;14) probe revealed clonal numerical abnormalities of chromosomes 11 and 14 in some cells. The detection of multiple abnormalities explains the bad prognosis in the present case. On the basis of our findings, we can easily conclude that results of cytogenetic analyses of similar mantle cell lymphoma patients would provide clues about new responsible gene regions and disease prognosis. In conclusion, it has been suggested that the presence of multiple chromosomal aberrations in addition to the specific t(11;14) may have a negative impact on clinical course and survival rate.

Management of mantle cell leukemia with cardiac involvement leading to cardiogenic shock

Mantle cell lymphoma is an aggressive subtype of B cell non-Hodgkin lymphoma. It can progress to leukemic phase but frank leukemic picture at initial presentation is not common. Leukemic phase indicates advance stage of the disease and generally associated with extensive extra-nodal involvement. Pericardial invasion has been reported, however we could not find a report of myocardial infiltration by this disease since the appraisal of the term "mantle cell lymphoma" in 1992. Here we report a case of cardiac involvement by mantle cell leukemia leading to cardiogenic shock which complicates the treatment decisions.

Clinical practice guidelines for diagnosis, treatment, and follow-up of patients with mantle cell lymphoma. Recommendations from the GEL/TAMO Spanish Cooperative Group

Mantle cell lymphoma (MCL) is considered a distinct type of B-cell lymphoma genetically characterized by the t(11;14) translocation and cyclin D1 overexpression. There is also a small subset of tumors negative for cyclin D1 expression that are morphologically and immunophenotypically indistinguishable from conventional MCL. Although in the last decades, the median overall survival of patients with MCL has improved significantly, it is still considered as one of the poorest prognoses diseases among B-cell lymphomas. Election of treatment for patients with MCL is complex due to the scarcity of solid evidence. Current available data shows that conventional chemotherapy does not yield satisfactory results as in other types of B-cell lymphomas. However, the role of other approaches such as autologous or allogenic stem cell transplantation, immunotherapy, the administration of consolidation or maintenance schedules, or the use of targeted therapies still lack clear indications. In view of this situation, the Spanish Group of Lymphomas/Autologous Bone Marrow Transplantation has conducted a series of reviews on different aspects of MCL, namely its diagnosis, prognosis, first-line and salvage treatment (both in young and elderly patients), new targeted therapies, and detection of minimal residual disease. On the basis of the available evidence, a series of recommendations have been issued with the intention of providing guidance to clinicians on the diagnosis, treatment, and monitoring of patients with MCL.

Genomic profiling of mantle cell lymphoma

Genomic profiling of mantle cell lymphoma (MCL) cells has enabled a better understanding of the complex mechanisms underlying the pathogenesis of disease. Besides the t(11;14)(q13;q32) leading to cyclin D1 overexpression, MCL exhibits a characteristic pattern of DNA copy number aberrations that differs from those detected in other B-cell lymphomas. These genomic changes disrupt selected oncogenes and suppressor genes that are required for lymphoma development and progression, many of which are components of cell cycle, DNA damage response and repair, apoptosis, and cell-signaling pathways. Additionally, some of them may represent effective therapeutic targets. A number of genomic and molecular abnormalities have been correlated with the clinical outcome of patients with MCL and are considered prognostic factors. However, only a few genomic markers have been shown to predict the response to current or novel targeted therapies. One representative example is the high-level amplification of the BCL2 gene, which predicts a good response to pro-apoptotic BH3 mimetic drugs. In summary, genomic analyses have contributed to the substantial advances made in the comprehension of the pathogenesis of MCL, providing a solid basis for the identification of optimal therapeutic targets and for the design of new molecular therapies aiming to cure this fatal disease.

Nuclei micro-array FISH, a desirable alternative for MCL diagnosis

Mantle cell lymphoma (MCL) is a rare, specific lymphoma subtype. Though the morphologic and immunophenotypic features of MCL have been well described in recent literatures, it is still a diagnostic dilemma because of its frequent confusion with other small B cell lymphomas (SBCLs). In the present study, we primarily focus on establishing a sensitive and specific method for the diagnosis of MCL, which is efficient to distinguish this disease from other SBCLs. We carried out our investigation for MCL and other SBCLs (including SLL, FL, MZL, and MALT) on their feature of morphology, immunophenotype, and t(11;14)(q13;q32) translocation analysis based on polymerase chain reaction (PCR) and interphase nuclei micro-array fluorescence in situ hybridization (FISH). The morphologic and immunologic analysis showed the positive rate of cyclin D1 was 76.47% in MCL, which was significantly higher than that in other SBCLs. The positive rate of t(11;14) translocation was 25.81% and 35.48%, respectively, tested by general and semi-nested PCR, while 93.10% positive rate was shown with low background and strong signals pattern when tested by Nuclei micro-array FISH. Our research shows that t(11;14) translocation is a special and useful diagnostic marker for MCL, and detection of the marker by nuclei micro-array FISH is convenient and economic, especially more sensitive and specific than other methods for the diagnosis of MCL.

The basis and rational use of molecular genetic testing in mature B-cell lymphomas

An increasing number of neoplasms are associated with variably specific genetic abnormalities. This is best exemplified by hematological malignancies, in which there is a growing list of entities that are defined by their genetic lesion(s); this is not (yet) the case in mature B-cell lymphomas. However, enhanced insights into the pathogenesis of this large and diverse group of lymphomas have emerged with the ongoing unraveling of a plethora of fascinating genetic abnormalities. The purpose of this review is to synthesize well-recognized data and nascent discoveries in our understanding of the genetic basis of a spectrum of mature B-cell lymphomas, and how this may be applied to contemporary clinical practice. Despite the explosion of new and exciting knowledge in this arena, with the potential for enhanced diagnostic and prognostic strategies, it is essential to remain cognizant of the limitations (and complexity) of genetic investigations, so that assays can be developed and used both judiciously and rationally.

Genetic testing in orbital tumors

OBJECTIVE

This review aims to discuss the clinical application of cytogenetic and molecular testing in the diagnosis and prognosis of orbital tumors and, in so doing, highlight the basis of these methods, their advantages, and limitations.

SUMMARY

Specific chromosomal aberrations are detected in many lymphoproliferative neoplasms, soft tissue tumors, and in a few benign tumors of the orbit. Detection of these characteristic chromosomal translocations is most helpful to refine the diagnosis and classification, especially when the tumor is poorly differentiated and shows overlapping morphological features with another tumor type. This review outlines orbital tumors with characteristic chromosomal translocations and the relative frequency of detecting the genetic mutation. Various genetic techniques are available for genetic testing, including karyotyping, fluorescence in situ hybridization (FISH), reverse transcriptase polymerase chain reaction (RT-PCR), and genomic polymerase chain reaction (PCR). As yet, the newer methods of array-comparative genomic hybridization (array-CGH) and expression profiling are most commonly used in research settings or in large specialist centers, and their general application to cancer diagnostics is limited by their cost. Therefore, this review focuses on the methodologies that should be available to most diagnostic units. It is true that "one size does not fit all" in this field and that a combination of molecular techniques may be needed to confirm results at the genomic and transcriptional levels.

Susceptibility of mantle cell lymphomas to reovirus oncolysis

Mantle cell lymphoma (MCL) an incurable B-cell, non-Hodgkin lymphoma (NHL) urgently requires new treatments. We assessed reovirus mediated oncolysis in a panel of human MCL cell lines. In vitro, we found the cytopathic effect of reovirus infection ranged from high to very limited and correlated with levels of Ras activation. In vivo, a single reovirus injection intra-tumorally resulted in complete regression of both the injected and the contra-lateral tumor in a subcutaneous bi-tumor model, in one out of three cell lines tested. Reovirus treatment of MCL seems feasible but will need to be guided by the presence of molecular determinants of reovirus susceptibility.

[Monoclonal gammopathy and primary colonic mantle cell lymphoma]

The association of a monoclonal gammopathy (MG) with a B cell non-Hodgkin's lymphoma (NHL) is a well-known phenomenon. It has been recognized in many subtypes of primary gastrointestinal lymphoma but its association with primary colonic mantle cell lymphoma has never been yet described. We report a 65-year-old man who presented with an exudative ascites and constipation. Serum electrophoresis showed a monoclonal peak in the gamma region of 45g/L and immunoelectrophoresis confirmed the presence of monoclonal gammopathy of IgM kappa type. Bone marrow aspirate was normal. Radiologic and endoscopic investigations evidenced a primary colonic mantle cell lymphoma. Although the association of an MG with an NHL and, in particular, to a primitive digestive location appears a rare phenomenon, endoscopic investigations in patients with MG appears legitimate in the presence of any digestive sign.

CD38 gene polymorphism and chronic lymphocytic leukemia: a role in transformation to Richter syndrome?

CD38 rules proliferation signals in chronic lymphocytic leukemia (CLL) cells, suggesting that the molecule is not merely a prognostic marker but also a key element in the pathogenetic network underlying the disease. CD38 has a genetic polymorphism, characterized by a C>G variation in the regulatory region of intron 1. The working hypothesis is that the presence of different alleles in CLL patients marks (or accounts for) some of the clinical heterogeneity. CD38 allele distribution in 248 Italian patients overlapped with that of the controls (n = 232), suggesting that susceptibility to CLL is not influenced by CD38 genotype. Stratification of patients according to markers of unfavorable prognosis constantly resulted in a significantly higher frequency of the rare G allele. Furthermore, analysis of clinical parameters showed that G allele is independently associated with nodal/splenic involvement. The highest G allele frequency was observed in the 16 patients of the cohort that developed Richter syndrome (RS). Five-year cumulative incidence of transformation was significantly higher in G allele carriers than in CC homozygotes. Multivariate analysis on a total of 30 RS patients confirmed that the probability of transformation is strongly associated with G allele, likely representing an independent risk factor for RS development.