Rapid detection of the t(11;14) translocation in mantle cell lymphoma by interphase fluorescence in situ hybridization on archival cytopathologic material

A Proposal for the Performance, Classification, and Reporting of Lymph Node Fine-Needle Aspiration Cytopathology: The Sydney System

BACKGROUND

The evaluation of lymph nodes (LN) by fine-needle aspiration cytology (FNAC) is routinely used in many institutions but it is not uniformly accepted mainly because of the lack of guidelines and a cytopathological diagnostic classification. A committee of cytopathologists has developed a system of performance, classification, and reporting for LN-FNAC.

METHODS

The committee members prepared a document that has circulated among them five times; the final text has been approved by all the participants. It is based on a review of the international literature and on the expertise of the members. The system integrates clinical and imaging data with cytopathological features and ancillary techniques. The project has received the endorsement and patronage of the International Academy of Cytology and the European Federation of the Cytology Societies.

RESULTS

Clinical, imaging, and serological data of lymphadenopathies, indications for LN-FNAC, technical procedures, and ancillary techniques are evaluated with specific recommendations. The reporting system includes two diagnostic levels. The first should provide basic diagnostic information and includes five categories: inadequate/insufficient, benign, atypical lymphoid cells of undetermined/uncertain significance, suspicious, and malignant. For each category, specific recommendations are provided. The second diagnostic level, when achievable, should produce the identification of specific benign or malignant entities and additional information by utilizing ancillary testing.

CONCLUSION

The authors believe that the introduction of this system for performing and reporting LN-FNAC may improve the quality of the procedure, the report, and the communication between cytopathologists and the clinicians. This system may lead to a greater acceptance and utilization of LN-FNAC and to a better interdisciplinary understanding of the results of this procedure.

Detection of cryptic CCND1 rearrangements in mantle cell lymphoma by next generation sequencing

The accurate detection of recurrent genetic abnormalities for most hematologic neoplasms is critical for diagnosis, prognosis and/or treatment. Rearrangements involving CCND1 are observed in a subset of mature B-cell neoplasms and can be reliably detected by fluorescence in situ hybridization (FISH) in most cases. However, cryptic and complex chromosomal rearrangements may pose a technical challenge for accurate diagnosis. Herein, we describe two patients with suspected mantle cell lymphoma that lacked obvious CCND1 rearrangements by FISH studies. A next generation sequencing (NGS) based assay, mate-pair sequencing (MPseq), was utilized in each case to investigate potential cryptic CCND1 rearrangements and revealed cryptic insertional events resulting in CCND1/IGH and CCND1/IGK rearrangements. These cases demonstrate that NGS-based assays, including MPseq, are a powerful approach to identify cryptic rearrangements of clinical importance that are not detected by current clinical genomics evaluation.

Lymph Node Fine-Needle Cytology: Beyond Flow Cytometry

Lymph node (LN) fine-needle cytology (FNC) coupled with flow cytometry immunophenotyping provides relevant information for the diagnosis of non-Hodgkin lymphoma (NHL). Numerous studies have shown FNC samples to be suitable for different molecular procedures; in this review, some of the molecular procedures most commonly employed for NHL are briefly described and evaluated in this perspective. Fluorescence in situ hybridization and chromogenic in situ hybridization are briefly described. Polymerase chain reaction (PCR)-based assays are used to identify and quantify mutations and translocations, namely immunoglobulin (IGH) and T-cell receptor rearrangements by clonality testing and IGVH somatic hypermutations either by Sanger sequencing, single-strand conformational polymorphisms or RT-PCR strategies. High-throughput technologies (HTT) encompass numerous and different diagnostic tools that share the capacity of multiple molecular investigation and sample processing in a fast and reproducible manner. HTT includes gene expression profiling, comparative genomic hybridization, single-nucleotide polymorphism arrays and next-generation sequencing technologies. A brief description of these tools and their potential application to LN FNC is reported. The challenge for FNC will be to achieve new knowledge and apply new technologies to FNC, exploiting its own basic qualities.

Endoscopic/Endobronchial Ultrasound-Guided Fine Needle Aspiration and Ancillary Techniques, Particularly Flow Cytometry, in Diagnosing Deep-Seated Lymphomas

Evaluation of deep-seated lymphomas by fine-needle aspiration (FNA) can be challenging due to their reduced accessibility. Controversy remains as to whether FNA and ancillary techniques can be used to diagnose deep-seated lymphomas reliably and sufficiently for clinical management. Most published studies are favorable that endobronchial ultrasound (EBUS)/endoscopic ultrasound (EUS)-FNA plays an important role in the diagnosis of deep-seated lymphomas. The addition of ancillary techniques, particularly flow cytometry, increases diagnostic yield. While subclassification is possible in a reasonable proportion of cases, the reported rates of successful subclassification are lower than those for lymphoma detection/diagnosis. The diagnostic limitation exists for Hodgkin's lymphoma, grading of follicular lymphoma, and some T-cell lymphomas. The role of FNA in deep-seated lymphomas is much better established for recurrent than primary disease. It remains unclear whether the use of large-sized-needle FNA or a combination of core needle biopsy and FNA improves subclassification. It is important for cytopathologists to have considerable understanding of the WHO lymphoma classification and develop a collaborative working relationship with hematopathologists and oncologists. As EUS/EBUS-FNA techniques advance and sophisticated molecular techniques such as next- generation sequencing become possible, the role of FNA in the diagnosis of deep-seated lymphomas will possibly increase.

Mantle cell lymphoma: a report of 31 nodal and extranodal fine-needle aspirates

INTRODUCTION

This study reports our experience using aspiration cytopathology coupled with various auxiliary tests in achieving diagnostic accuracy in cases of mantle cell lymphoma (MtCL) from both nodal and extranodal sites.

MATERIALS AND METHODS

Specimens retrieved from our cytology database used search codes for MtCL. Tissue files were searched for any cases of MtCL that had corresponding fine-needle aspiration biopsy (FNAB) cytopathology. FNAB was performed using the standard technique.

RESULTS

Thirty-one aspirates of MtCL were recovered: 11 primary and 20 recurrent examples over a wide age range (x = 63 years). All had histologic confirmation. Nearly one-half were from extranodal sites (14; 45%), mostly representing skin/soft tissue masses. Microscopic examination showed a monotonous proliferation of small-medium lymphocytes in a dispersed pattern with dendritic cells and rarely tingible-body macrophages. Flow cytometry (FCM) performed on all but 6 aspirates demonstrated light chain clonality. In 12 aspirates, ancillary testing in addition to FCM consisted of fluorescence in situ hybridization only (6 cases), fluorescence in situ hybridization plus immunohistochemical (IHC) (2), and IHC only (4). One case had cell block IHC alone without FCM. A specific diagnosis of MtCL was made from 45% of primary and 89% of recurrent MtCL cases. No examples of a correct, specific FNAB diagnosis of MtCL were made without the use of some form of auxiliary testing.

CONCLUSIONS

Aspirates of MtCL are characterized by nonspecific relatively uniform small-sized to medium-sized lymphocytes. A specific diagnosis of MtCL is achievable in nodal/extranodal sites, but only when a combination of auxiliary studies is judiciously employed.

The Diagnostic Value of Flow Cytometry Imunophenotyping in an Albanian Patient Population with a Preliminary Clinical Diagnosis of Chronic Lymphocytic Leukemia

Objective: Based on the flow cytometry multiparametric immunophenotyping methodology we studied some useful cell marker criteria needed for the practical differentiation of the chronic lymphocytic leukemia from other chronic limphoproliferative diseases with a leukemic component.Materials and Methods: The applied methodology is a four color flow cytometry multiparametric immunophenotyping technique using EDTA blood samples taken from 84 consecutive patients diagnosed with CLL through a preliminary clinical and white blood cell examination. The following fluorescent stained monoclonal antibodies were used: CD3, CD4, CD5, CD8, CD11c, CD19, CD20, CD23, CD25, FMC7 and kappa/lambda light chains.Results: From the 84 individuals tested, 2 out of them (2.4%) resulted with a abnormal T-cell population while 82 (97.6%) showed a pathological B cell line. 58 (69.1%) patients resulted with typical CLL markers (CD19+CD5+CD23+) while 5 (5.9%) of them presented a non typical chronic lymphocytic leukemia profile (CD19+CD5+CD23-). 19 (22.6%) out of patients displayed an abnormal CD19+CD5- B cell population. A statistically significant correlation was found between the clinical stage of CLL and the positivity for the CD38 marker (p=0.04).Conclusion: Flow cytometry immunophenotyping is a fundamental examination for the final diagnosis of chronic lymphocytic leukemia. The expression of CD38+ in CLL patients stands for a more advanced clinical stage.

Ancillary techniques on direct-smear aspirate slides: a significant evolution for cytopathology techniques

Numerous cytologic techniques aimed at effectively acquiring patient material for molecular testing have been proposed. Such techniques are becoming ever more important in an age of personalized medicine. In this commentary, the authors explored some more commonly proposed techniques to aid in the molecular testing of cytologic specimens. These techniques include the use of cell blocks, direct cytologic smears, filter paper storage, frozen samples, and enriched cellular techniques such as ThinPrep and cytospin preparations. Direct-smeared slides demonstrate excellent preservation of DNA, are easy to prepare, and are amenable to immediate adequacy at the time of the fine-needle aspiration (FNA) procedure as well as effective subsequent tumor purity estimation. Cell block methods cannot be assessed at the time of FNA and often demonstrate insufficiency, whereas filter paper and frozen techniques do not allow for the direct assessment of the presence and purity of tumor cells in the sample. Direct-smeared slides are emerging as the most effective preparation and storage medium of cytologic material to be used for molecular testing. Their cost-effectiveness, ease of use, and reliability have cemented them as the optimal solution for cytopathologists to fulfill the role of providing advanced molecular testing on patient samples.

[Role of cytology in hematopathological diagnostics]

The role of cytology has so far been underrecognized in the diagnostic process of hematopathological questions. This article presents an algorithm which allows a stepwise work-up of cytology specimens obtained by minimally invasive ultrasound-guided fine needle aspiration in patients with unexplained lymph node swelling. Moreover, it is shown how the selective separation of cytology specimens allows the application of immunophenotypic analysis including flow cytometry and immunohistochemistry as well as molecular analyses, such as fluorescence in situ hybridization (FISH) and polymerase chain reaction (PCR) strategies. With the integrative procedure presented, cytology offers an excellent cost-effective tool for the diagnostic approach of patients with suspected hematopathological malignancies allowing a high diagnostic accuracy, ideal for initial diagnosis or follow-up.

Endoscopic ultrasound and endobronchial ultrasound-guided fine-needle aspiration of deep-seated lymphadenopathy: Analysis of 1338 cases

Background:

We retrospectively studied 1338 samples of lymph nodes obtained by endoscopic and endobronchial ultrasound-guided fine needle aspiration biopsy (EUS and EBUS-FNAB) with an objective of characterizing the utility of this diagnostic modality in the assessment of deep-seated lymphadenopathy. The secondary aims were to establish the utility in the diagnosis of lymphoma and to determine the number of passes required to obtain adequate cellularity for flow cytometric analysis.

Materials and Methods:

On-site assessment was performed by a cytopathologist using Diff-Quik (American Scientific Products, McGraw Park, IL) stain. In addition, Papanicolaou and immunohistochemical stains were performed and additional samples were sent for flow cytometric analyses (n = 145). The final cytologic diagnosis was correlated with surgical pathology diagnosis and/or clinical follow-up. In select cases, fluorescence in situ hybridization analysis with specific probes was performed on Diff-Quik smears.

Results:

Both morphology as well as ancillary studies (flow cytometry or immunohistochemical stain and/or fluorescence in situ hybridization) show that EUS and EBUS-FNA are effective techniques to detect and stage intrathoracic and intra-abdominal tumors. Operating characteristics show that these are highly sensitive (89%) and specific (100%) techniques for the diagnosis of lymphoma. At least two passes provided an average of 5.66 million cells (range, 0.12-62.32 million) for lymphoma cases.

Conclusions:

EUS and EBUS-FNA are powerful modalities to stage malignancies and at least two passes can provide adequate cells for flow cytometric analysis. We also demonstrate that fluorescence in situ hybridization analysis can be performed on Diff-Quik-stained and mounted smears.

Immunoglobulin heavy-chain fluorescence in situ hybridization-chromogenic in situ hybridization DNA probe split signal in the clonality assessment of lymphoproliferative processes on cytological samples

BACKGROUND

The human immunoglobulin heavy-chain (IGH) locus at chromosome 14q32 is frequently involved in different translocations of non-Hodgkin lymphoma (NHL), and the detection of any breakage involving the IGH locus should identify a B-cell NHL. The split-signal IGH fluorescence in situ hybridization-chromogenic in situ hybridization (FISH-CISH) DNA probe is a mixture of 2 fluorochrome-labeled DNAs: a green one that binds the telomeric segment and a red one that binds the centromeric segment, both on the IGH breakpoint. In the current study, the authors tested the capability of the IGH FISH-CISH DNA probe to detect IGH translocations and diagnose B-cell lymphoproliferative processes on cytological samples.

METHODS

Fifty cytological specimens from cases of lymphoproliferative processes were tested using the split-signal IGH FISH-CISH DNA probe and the results were compared with light-chain assessment by flow cytometry (FC), IGH status was tested by polymerase chain reaction (PCR), and clinicohistological data.

RESULTS

The signal score produced comparable results on FISH and CISH analysis and detected 29 positive, 15 negative, and 6 inadequate cases; there were 29 true-positive cases (66%), 9 true-negative cases (20%), 6 false-negative cases (14%), and no false-positive cases (0%). Comparing the sensitivity of the IGH FISH-CISH DNA split probe with FC and PCR, the highest sensitivity was obtained by FC, followed by FISH-CISH and PCR.

CONCLUSIONS

The split-signal IGH FISH-CISH DNA probe is effective in detecting any translocation involving the IGH locus. This probe can be used on different samples from different B-cell lymphoproliferative processes, although it is not useful for classifying specific entities. Cancer (Cancer Cytopathol) 2012;. © 2012 American Cancer Society.

Fine needle aspiration (FNA) cytology for diagnosis of cervical lymphadenopathy

Patients with cervical adenopathy suspicious for malignancy are often referred to the Otolaryngology Service for tissue diagnosis. Confirmation of nodal involvement by upper aero-digestive tract tumors (UADT) is best obtained by fine needle aspiration (FNA). Reported studies of FNA for lymphoma diagnosis have yielded conflicting results. Retrospective review of charts and pathology of 161 patients diagnosed with lymphomas yielded 53 patients with cervical adenopathy without apparent UADT. FNA's were performed on 28, and were repeated nine times, for a total of 37. Eleven had Hodgkin's disease and 17 other types of lymphomas. Seven of 37 specimens contained only blood; 15 contained lymphoid cells, nine of which were designated "reactive." Lymphoid cells designated as "atypical" or "suspicious for lymphoma" were found in 13 of the 37 aspirates. Two were diagnostic of lymphoma. Lymphoma was confirmed by histopathologic specimens in all patients, obtained 0-941 days (median 15, mean 73 days) after initial FNA. In lymphoma patients with cervical lymphadenopathy, FNA does not usually suffice for, and often leads to significant delays in diagnosis.

Interferon-alpha for maintenance of follicular lymphoma

BACKGROUND

Indolent non-Hodgkin's lymphoma, in particular follicular lymphoma (FL), is characterized by multiple remissions and relapses. Several studies have used interferon-alpha (IFN) to control this disease, both as induction and as maintenance therapy. It is not yet clear whether IFN can be associated with a survival benefit although it may prolong progression-free survival.

OBJECTIVES

To determine the effects of IFN in the maintenance therapy of FL.

SEARCH STRATEGY

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library, Issue 4, 2008), MEDLINE (1966 to 2008), DARE (1990 to 2008), SCOPUS (searched December 2008) and Current Contents (1975 to 2008). .

SELECTION CRITERIA

Randomised controlled trials of IFN versus no intervention or placebo, or IFN plus chemotherapy versus chemotherapy alone, in a maintenance setting in patients with non-Hodgkin's FL. Primary outcomes were overall survival and progression-free survival.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trial quality and extracted data. We contacted study authors for additional information. We collected adverse events information from the trials.

MAIN RESULTS

We included eight trials (1563 patients). The drug was IFN alfa-2b in six trials and alfa-2a in two. Trials were heterogeneous in terms of diagnosis of FL, using several classification systems. IFN had been compared with placebo/no intervention in five trials and other chemotherapy in three. The effect of IFN was similar to that of placebo on overall survival (hazard ratio (HR) 0.90, 95% CI 0.61 to 1.34) whereas IFN was more effective when added to chemotherapy (HR 0.68, 95% confidence interval (CI) 0.52 to 0.90). Considering IFN versus all comparators, IFN was effective in prolonging progression-free survival (HR 0.66, 95% CI 0.57 to 0.77) and overall survival (fixed effects HR 0.79, 95% CI 0.67 to 0.94, I(2) = 52%). After adjustment for heterogeneity this statistically significance disappeared (random effects HR 0.82, 95% CI 0.63 to 1.08). Toxicity and patients lost to follow up were significantly higher in the IFN groups.

AUTHORS' CONCLUSIONS

There is evidence that addition of IFN as maintenance therapy for FL improves progression-free survival. A net benefit for overall survival is less evident. In the included studies, IFN was associated with significant toxicities that may have a major impact on a patient's quality of life.

CD5-positive mucosa-associated lymphoid tissue (MALT) lymphoma of ocular adnexal origin: usefulness of fluorescence in situ hybridization for distinction between mantle cell lymphoma and MALT lymphoma

Extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue type (MALT lymphoma) usually lacks CD5 expression. Herein is described two cases of CD5-positive MALT lymphoma of ocular adnexal origin. The differential diagnosis between CD5-positive MALT lymphoma and mantle cell lymphoma (MCL), notably cyclin D1-negative MCL, was difficult because both cases consisted histologically of small to medium-sized cells with diffuse or vaguely nodular growth pattern, and the neoplastic cells were positive for CD5 and negative for cyclin D1. Somatic mutation analysis of the immunoglobulin heavy chain variable region (VH) gene in case 1 found a relatively higher mutation frequency (5.0%), which was not definitive to rule out MCL. Interphase fluorescence in situ hybridization (FISH) on paraffin-embedded section using IgH/cyclin D1 (CCND1) probe showed that in both cases there was no molecular evidence of t(11;14), finally leading to the diagnosis of CD5-positive MALT lymphoma. Although the present two patients had no recurrence over 34 months after initial diagnosis, careful observation is needed because the clinicopathological significance of MALT lymphoma with this rare phenotype remains obscure.

Applications of molecular techniques to fine-needle aspiration biopsy

The effectiveness of fine-needle aspiration biopsy (FNAB) for rendering a specific diagnosis can be improved by applying several ancillary modalities. This review details several applications of molecular techniques using FNAB specimens with an emphasis on those used for patient care. A detailed search of the literature was conducted to collect all reports that used FNAB for different types of molecular tests. Several types of molecular tests, including in-situ hybridization, polymerase chain reaction, Southern blotting, and gene microarrays using FNAB specimens have been reported. These tests have been used with different organ systems and different objectives, including the detection of cancer cells, diagnosis, distinction of benign and malignant disease, prediction of response to chemotherapy, risk assessment, and selection of patients for targeted therapy. Except for a few tests such as assessment of HER2/neu for gene amplification in breast cancer, detection of clonality in hematopoietic neoplasms, and specific chromosomal translocations in the former and in the diagnosis of soft tissue sarcoma, most of the molecular tests using FNAB specimens are currently investigational. The reported literature indicates the excellent potential of using material procured from FNAB for almost any type of molecular test. Whereas few of these tests alone are used for patient care, some of them have the potential for clinical use in the near future.

Role of ancillary techniques in diagnosing and subclassifying non-Hodgkin's lymphomas on fine needle aspiration cytology

Non-Hodgkin's lymphomas (NHL) are tumours of the lymphoid cells. During the process of development of lymphoid cells, neoplasia may evolve at any point. Neoplastic cells usually carry the imprint of cell of origin at the stage of origin. Various types of NHL may have similar morphology with wide variation in origin, immunophenotype and other biological features. Different ancillary laboratory techniques may help to overcome the limitations of morphology in this aspect. The commonly used ancillary techniques in lymphomas are immunocytochemistry (IC), flow cytometry, Southern blot (SB) technique, polymerase chain reaction (PCR) and fluorescent in situ hybridization (FISH). In addition, laser scanning cytometry (LSC) and DNA microarray technologies are in the research phase. Various laboratory techniques are used for immunophenotyping, demonstration of monoclonality, identification of chromosomal translocation, assessment of cell kinetics and expression of mRNA in the tumour cells. Flow cytometry helps in rapid immunophenotying of NHL and it has an added advantage over IC in recognizing the co-expression of CD markers. Fine needle aspiration cytology (FNAC) combined with flow immunophenotyping may help us to diagnose and subclassify certain NHLs, such as follicular lymphoma and mantle cell lymphoma, which were previously recognized as pure morphological entities. Loss of morphology is one of the important limitations of flow cytometry. LSC can overcome this limitation by studying morphology along with the immunophenotyping pattern of individual cells. Chromosomal changes in NHL can be identified by SB, PCR and FISH. Molecular diagnosis of NHL helps in diagnosis, subclassification, prognostic assessment and even in planning of therapy. DNA microarray is a relatively newer and promising technology. It gives information about the expression of several thousands of genes in a tumour in a single experiment. In the near future, FNAC combined with ancillary techniques may play a major role in diagnosis, subclassification and management of lymphomas.

Tumor Cell Nuclei Extraction From Paraffin-Embedded Lymphoid Tissue for Fluorescence In Situ Hybridization

In this study the authors evaluated a technique for isolating intact tumor nuclei from paraffin-embedded lymphoma samples before performing FISH testing to detect the lymphoma-specific trans-location t(11;14) that defines mantle cell lymphoma. Well-characterized surgical pathology cases of mantle cell lymphoma were identified from pathology archives. Thin sections were cut from the paraffin-embedded tissue blocks. One section was stained using hematoxylin and eosin and an area composed exclusively of malignant cells was identified and marked on the slide. The corresponding area of the tissue block corresponding to this region underwent needle core biopsy, and the tissue was processed to isolate tumor cell nuclei and deposited onto a glass slide. The paired sample preparations underwent routine FISH testing for detection of the t(11;14)(q13;q32) chromosomal trans-location. DNA probe hybridization quality was compared between the tissue and isolated nuclei. Individual tumor cell nuclei were successfully extracted from each of the tissue blocks. The t(11;14) trans-location was detected by FISH in all of the samples diagnosed as mantle cell lymphoma. The hybridization signals found in the nuclei of extracted tumor cells were bright, planar, and easily identified. Detection of signal was superior to that on whole tissue samples, where signals often overlapped or were truncated. This technique produces intact nuclei for analysis, preserves the tissue block for additional studies, and allows sampling of a specific area of the tissue block. This approach may be particularly useful when the amount of diagnostic tissue is limited.

Cytogenetics of lymphomas

Cytogenetic analysis is now a routine part of the diagnosis and management of a significant number of lymphoid malignancies. Whilst conventional cytogenetics remains the most comprehensive method for assessing chromosome abnormalities, the technical difficulties associated with conventional cytogenetics in most lymphomas has resulted in increased use of fluorescence in situ hybridisation (FISH) to identify specific abnormalities that are useful in either the diagnosis or management of these disorders. The finding of one of the Burkitt's translocations is of major importance in the diagnosis of Burkitt's and Burkitt's-like lymphomas, whereas the t(14;18), although seen in most follicular lymphomas (FL), is not usually required to make a diagnosis. Thus, whilst cytogenetics may be of interest in FL, it is not an essential part of the diagnostic work-up. Conventional cytogenetics may be useful for identifying markers of resistance to Helicobacter pylori therapy in MALT lymphomas. In disorders such as Hodgkin lymphoma, hairy cell leukaemia and lymphoplasmacytoid lymphoma, although many cytogenetic abnormalities have been observed, no consistent or specific abnormalities have been identified and so, at this point in our knowledge of the genetics of these disorders, cytogenetics cannot be considered a useful test for either diagnosis or prognosis. In contrast, the diagnosis of mantle cell lymphoma is now dependent upon the identification of the 11;14 translocation that results in cyclin D1 up-regulation. It is widely acknowledged that FISH is the most consistently useful test to identify the juxtaposition of the CCND1 and IGH genes in mantle cell lymphoma and is regarded as the 'gold standard'. FISH also has a role in identifying genetic abnormalities of prognostic significance in chronic lymphocytic leukaemia. Given the wealth of genetic and cytogenetic abnormalities that are continuing to be found in chronic lymphoid malignancies, it will be some time before the optimal use of both conventional cytogenetics and FISH is established in the diagnosis and management of lymphomas.

Current Treatment Approaches for Mantle-Cell Lymphoma

Mantle-cell lymphoma (MCL) is now recognized as a distinct clinicopathologic subtype of B-cell non-Hodgkin's lymphoma. Patients with MCL are typically older adults with a male predominance and usually present with stage IV disease. The cells are characterized as CD20+CD5+CD23−with a t(11;14)(q13;q32) and cyclin D1 overexpression on immunohistochemistry. Response to chemotherapy usually results in a tumor response but unmaintained remissions are short and the median survival is 3 to 4 years. The treatment approach to newly diagnosed patients with MCL depends on the patient's eligibility for stem cell transplantation (SCT). Those who are eligible are usually treated with either rituximab-CHOP (cyclophosphamide, doxorubicin, vincristine, and prednisone) followed by SCT or rituximab-HyperCVAD (cyclophosphamide, vincristine, doxorubicin, decadron, cytarabine, and methotrexate) followed by observation. The purine nucleoside analogues also have activity as single agents and with rituximab. Unfortunately none of these approaches can definitively cure patients with MCL, and new agents are needed. Recent studies in patients with relapsed MCL have shown substantial antitumor activity of single-agent bortezomib, single-agent temsirolimus, and the combination of thalidomide and rituximab. Studies integrating these novel agents earlier in the disease course or in combination with each other will hopefully produce more durable responses with less toxicity.

Lymphoma associated chromosomal abnormalities can easily be detected by FISH on tissue imprints. An underused diagnostic alternative

BACKGROUND

Fluorescence in situ hybridisation (FISH) is useful for detecting specific chromosomal abnormalities in various tumours. In lymphomas, diagnosis is frequently made using paraffin wax embedded tissue. However, FISH performed under these conditions presents potential technical problems and difficulties in interpretation.

AIMS

To show that FISH using tissue imprints and cytopreps or alternatively, bone marrow (BM) smears, constitutes an easy and rapid strategy to overcome these constraints.

METHODS

The study comprised 46 patients with lymphoma. Sixty nine tissue imprints, cytopreps, or BM smears were analysed by FISH. Dual colour, dual fusion FISH probes were used to detect the t(8;14), t(11;14), and t(14;18) translocations, whereas a dual colour breakapart FISH probe was used to detect chromosomal translocations involving the BCL6 gene.

RESULTS

Tissue imprints and cytopreps were successfully hybridised in all 52 cases, whereas hybridisation was successful in 16 of 17 archival BM smears. All patients could be analysed to identify either the presence or absence of chromosomal translocations.

CONCLUSIONS

The use of tissue imprints, cytopreps, or BM smears to identify chromosomal abnormalities by FISH is a rapid and useful ancillary approach for diagnostic purposes. Therefore, it could be used on a routine basis whenever fresh samples are available.

The utility of interphase fluorescence in situ hybridization for the detection of the translocation t(11;14)(q13;q32) in the diagnosis of mantle cell lymphoma on fine-needle aspiration specimens

BACKGROUND

Mantle cell lymphoma can be difficult to differentiate cytologically from other small cell non-Hodgkin lymphomas. Nevertheless, the distinction is important, because mantle cell lymphoma is more aggressive than other small cell non-Hodgkin lymphomas. The purpose of this study was to determine whether fluorescence in situ hybridization (FISH) is helpful in diagnosing mantle cell lymphoma on fine-needle aspiration (FNA) specimens by detecting the t(11;14)(q13;q32) translocation that is characteristic of this tumor.

METHODS

Fifty-five lymph node FNA specimens from 53 patients were analyzed using FISH. A 2-color FISH assay that employed probes at the 14q32 (immunoglobulin H) and 11q13 (dual-colored, directly labeled cyclin D1) loci was used. The number of single-fusion and double-fusion signals in 200 cells was counted. If > or = 14% single-fusion signals or > or = 1.5% double-fusion signals or both were present, then the sample was considered FISH positive. The findings were correlated with the cytologic, histologic, and immunophenotypic findings in each specimen.

RESULTS

Of the 55 cytology specimens, 17 were mantle cell lymphomas, and 38 were nonmantle cell lymphomas, including 16 small lymphocytic lymphomas (9 of 16 in an accelerated phase), 5 large cell lymphomas, 5 follicular lymphomas, 7 transformed large cell lymphomas (Richter syndrome), 3 atypical lymphoid proliferations, and 2 low-grade B-cell lymphomas. All 17 mantle cell lymphomas were positive by FISH. In addition, there were six small lymphocytic lymphomas (two in accelerated phase), one transformed large cell lymphoma, and one large cell lymphoma of follicular origin positive by FISH. The mean number of single-fusion and double-fusion signals, respectively, was 36 and 33 in mantle cell lymphoma specimens and 19 and 3 in positive nonmantle cell lymphoma specimens.

CONCLUSIONS

The detection of the t(11;14)(q13;q32) translocation by FISH analysis was helpful in diagnosing mantle cell lymphoma on FNA specimens. Double-fusion signals were more specific for mantle cell lymphoma than single-fusion signals. In rare instances, other non-Hodgkin lymphomas also showed increased numbers of single-fusion signals that were not necessarily indicative of the t(11;14)(q13;q32) translocation. Therefore, in an initial diagnosis of mantle cell lymphoma, significant numbers of double-fusion FISH signals should be identified and interpreted in conjunction with the cytologic and immunologic studies.

The Value of Fluorescence In Situ Hybridization and Polymerase Chain Reaction in the Diagnosis of B-Cell Non-Hodgkin Lymphoma by Fine-Needle Aspiration

Context.—Molecular genetic analyses have been predicted to improve the diagnostic accuracy of fine-needle aspiration of B-cell non-Hodgkin lymphoma.

Objective.—To determine the value of routine molecular genetic assays, polymerase chain reaction (PCR) and fluorescence in situ hybridization (FISH), in the diagnosis of B-cell non-Hodgkin lymphoma by fine-needle aspiration (FNA).

Design.—A multiparametric method, including cytology, flow cytometry, PCR, and FISH, was prospectively evaluated in the diagnosis of B-cell non-Hodgkin lymphoma by FNA. Aspirates from 30 consecutive patients with suspected hematolymphoid malignancies were collected. All aspirates were triaged through a uniform program including cell-size analysis, B- and T-cell clonality studies, flow cytometric immunophenotyping, and bcl-1 and bcl-2 gene rearrangements by PCR and FISH. After completion of FNA evaluations, FNA results were compared with diagnoses from prior or subsequent surgical biopsies.

Results.—Monoclonal B-cell populations were detected in 18 of 20 B-cell non-Hodgkin lymphomas by flow cytometry and PCR. bcl-1 gene rearrangement was detected in 2 of 2 cases of mantle cell lymphoma. bcl-2 rearrangement was detected in 5 cases including 4 of 4 low-grade follicular lymphomas and 1 transformed follicular lymphoma. By incorporating the results of molecular genetic and ancillary diagnostics, a definitive classification was reached in 12 cases of B-cell non-Hodgkin lymphoma by FNA, including all cases of low-grade follicular lymphoma (4/4) and mantle cell lymphoma (2/2) and approximately 50% of small lymphocytic lymphoma (2/4) and large B-cell lymphoma (4/8). Ten of the 12 cases with a final classification reached by FNA had either prior or follow-up surgical biopsies, and all 10 cases showed agreement between the diagnoses rendered on FNA and surgical biopsies.

Conclusions.—With proper handling and management of specimens, FNA can routinely provide samples adequate for molecular genetic studies, in addition to cytomorphology and flow cytometry, making it possible to consistently render accurate and definitive diagnoses in a subset of B-cell non-Hodgkin lymphomas. By incorporating FISH and PCR methods, FNA may assume an expanded role for the primary diagnosis of B-cell non-Hodgkin lymphoma.