Utility of microdissection and polymerase chain reaction for the detection of immunoglobulin gene rearrangement and translocation in primary intraocular lymphoma

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.

Biopsy techniques and yields in diagnosing primary intraocular lymphoma

A review of current biopsy techniques that are used in obtaining specimens from which to make a diagnosis of primary intraocular lymphoma (PIOL) is presented. Methods for obtaining and subsequently testing vitrectomy specimens are discussed. In addition, the yields of external and internal approaches for obtaining chorioretinal tissue, and diagnostic vitrectomies, are reviewed.

IL-10 measurement in aqueous humor for screening patients with suspicion of primary intraocular lymphoma

PURPOSE

To determine the value of IL-10 measurement in aqueous humor (AH) for screening in primary intraocular lymphoma (PIOL).

METHODS

One hundred consecutive diagnostic or therapeutic vitrectomies were performed in patients with uveitis. During surgery, 100 microL of both AH and pure vitreous was taken. IL-10 levels were determined with a standard quantitative sandwich enzyme immunoassay technique. Patients were distributed in two groups: 51 patients with proven PIOL, 108 patients with uveitis divided into 74 with uveitis of proven etiology and 34 with idiopathic uveitis. Groups were compared by ANOVA and the Tukey-Kramer test or nonparametric Wilcoxon test. Distributions were compared by using the chi(2) test. Segmentation was derived from the ROC curves by choosing a tradeoff between sensitivity and specificity.

RESULTS

In patients with PIOL, IL-10 mean values were 2205.5 pg/mL (median: 1467 pg/mL) in the vitreous and 543.4 pg/mL (median: 424 pg/mL) in AH. In patients with uveitis (idiopathic and diagnostic uveitis), mean values were 26.6 pg/mL (median: 8 pg/mL) in the vitreous, and 21.9 pg/mL (median: 8 pg/mL) in AH. IL-10 mean values were significantly different between patients with PIOL and patients with uveitis (P < 10(-3)). The areas under the curves were 0.989 and 0.962 for vitreous and AH, respectively. A cutoff of 50 pg/mL in the AH was associated with a sensitivity of 0.89 and a specificity of 0.93. In the vitreous, a cutoff value of 400 pg/mL yielded a specificity of 0.99 and a sensitivity of 0.8.

CONCLUSIONS

Diagnosis of PIOL is often made months or years after the initial onset of ocular symptoms. Cytology remains the gold standard for diagnosis. However, measurement of IL-10 in the AH is a good screening test to reduce diagnostic delays.

Protocol for the use of polymerase chain reaction in the detection of intraocular large B-cell lymphoma in ocular samples

To determine the usefulness of polymerase chain reaction (PCR) analyses in the diagnosis of lymphoid infiltrate cells in ocular samples, PCR was performed using oligonucleotide primers specific for immunoglobulin heavy chain rearrangement at framework 2, framework 3, and t(14;18) translocation of the bcl-2 gene. These were used to successfully generate amplicons of 220 to 230 bp, 110 to 120 bp, and 175 to 200 bp, respectively. After PCR amplification, primers directed against the t(14;18) detected 10 pg of B-cell lymphoma DNA. PCR against Fr2 and Fr3 IgH rearrangement detected 10 fg and 10 pg in the seminested PCR, respectively. Conventional pathological methods were highly accurate at establishing the correct final diagnosis in formalin-fixed, paraffin-embedded samples but were much less sensitive and predictive in cytological specimens of intraocular fluid. A combination of the three PCR reactions was an equally successful diagnostic approach on paraffin-embedded samples, whereas single PCR reactions did not significantly improve diagnosis over histopathological diagnostic techniques. Thus, a combination of PCR reactions is useful in the detection of B-cell monoclonality, aids the differentiation between lymphomatous and inflammatory infiltrates, and is more powerful as a diagnostic method than single PCR or conventional cytopathology for lymphoid infiltrates in ocular fluid aspirates.

Primary intraocular lymphoma: improving the diagnostic procedure

OBJECTIVE

To analyze the clinical features of primary intraocular lymphoma (PIOL) and to describe cytochemical and immunocytochemical findings of the vitreous specimens as well as the reasons for delayed diagnosis of PIOL.

DESIGN

Prospective noncomparative study.

PARTICIPANTS

Eleven patients referred to the uveitis or medical retina units, Department of Ophthalmology, University of Helsinki, were diagnosed as having PIOL between 2000 and 2005. The median follow-up of the patients was 32 months.

METHODS

Clinical features and diagnostic workup of uveitis were described. Twelve vitrectomies were performed on 9 patients. The first 5 biopsies were fixed in an equal volume of 50% alcohol. The specimens of the next 7 vitrectomies were handled without alcohol, and tissue culture medium was added to the samples.

MAIN OUTCOME MEASURES

Clinical features of PIOL, intervals from ocular symptoms and from first ophthalmological examination to diagnosis, and the role of a proper handling of the vitreous sample in the diagnosis of PIOL.

RESULTS

Six females (54%) and 5 males (46%) (median age, 61 years) were included. Ten patients had ocular symptoms for 1 to 30 months (median, 8) before the first contact with an ophthalmologist. Uveitis was bilateral in 9 patients. Vitreitis was seen in all patients, and it was severe in 8. Fundus lesions dominated in 3 patients. Six patients lost useful vision in one eye before the diagnosis of PIOL. Cytologic and immunohistochemical stainings prepared of the unfixed vitreous specimens showed PIOL in 6 patients. The samples fixed in alcohol were nondiagnostic in 4 patients, and in them, verification of diagnosis was based on brain biopsy (3) or cerebrospinal fluid (1) findings. Seven patients died due to primary nervous system lymphoma.

CONCLUSIONS

Diagnosis of PIOL is difficult but can be improved. Severe bilateral vitreitis in an elderly patient is a characteristic finding of PIOL. Alcohol fixation may jeopardize the identification of PIOL cells in the vitreous sample. Optimal handling of the vitreous specimens and examination of the slides by an experienced cytopathologist are critical in the diagnostic workup of PIOL.

Clinical Applications of the Polymerase Chain Reaction: An Update

The development, in the past decade, of nucleic acid amplification and detection methods is useful in the study of the etiopathogenesis, diagnosis, and management of a variety of clinical (including rheumatologic) disorders. An association between infectious agents and rheumatic disorders has been established through such methods as polymerase chain reaction. This article describes the principles behind polymerase chain reaction-based diagnosis and updates its clinical applications. It is beyond the scope of this article, however, to describe other nucleic acid amplification methods or to include a complete list of all polymerase chain reaction assays that have been developed. Other recent reviews offer additional details.

Detection of the bcl-2 t(14;18) translocation and proto-oncogene expression in primary intraocular lymphoma

PURPOSE

Primary intraocular lymphoma (PIOL) is a diffuse large B cell lymphoma that initially infiltrates the retina, vitreous, or optic nerve head, with or without central nervous system involvement. This study examined the expression of the bcl-2 t(14;18) translocation, the bcl-10 gene, and high expression of bcl-6 mRNA in PIOL cells.

METHODS

Microdissection and PCR analysis were used to examine vitreous specimens in patients with PIOL for the presence of bcl-2 t(14;18) translocations, the bcl-10 gene, and expression of bcl-6 mRNA. A medical record review was also conducted to determine whether the bcl-2 t(14;18) translocation correlated with prognosis.

RESULTS

Forty of 72 (55%) PIOL patients expressed the bcl-2 t(14;18) translocation at the major breakpoint region. Fifteen of 68 (22%) patients expressed the translocation at the minor cluster region. The bcl-10 gene was detected in 6 of 26 (23%) patients, whereas 4 of 4 (100%) PIOL patients expressed higher levels of bcl-6 mRNA compared with inflammatory lymphocytes. An analysis of clinical outcome in 23 PIOL patients revealed no significant association between bcl-2 t(14;18) translocations and survival or relapse. However, patients with the translocation were significantly younger.

CONCLUSIONS

PIOL has unique molecular patterns of bcl-2, bcl-10, and bcl-6 when compared with other systemic lymphomas. This study lays the foundation for future studies aimed at exploring the genotypic classification of PIOL based on the quantitative molecular framework of gene expression profiling, with the goal of providing useful adjuncts to the pathologic diagnosis of this complex disease.

Primary Lymphoma of the Nervous System

This review article provides guidelines for the diagnosis, staging, and management of primary nervous system lymphoma based on the results of clinical trials conducted during the last decade. Recent progress in our understanding of the pathogenesis of primary nervous system lymphoma is summarized, and implications of these findings for the development of diagnostic tools and new therapeutic strategies are outlined. We performed a search of the PubMed database (National Center for Biotechnology Information) for articles on primary nervous system lymphoma published between 1970 and May 2005. Primary nervous system lymphoma affects the brain, eye, and meninges as well as cranial, spinal, and peripheral nerves. Although important lessons have been learned from the pathogenesis of extraneural non-Hodgkin's lymphoma, the unique organotropism of primary nervous system lymphoma remains poorly understood. Diagnosis is facilitated by modern imaging techniques and molecular markers. Clinically recognizable "precursors" may exist but frequently elude specific diagnosis. Insight into the peculiar pharmacokinetics of chemotherapy aimed at tumors within the nervous system has led to the development of methotrexate-based regimens that can achieve prolonged progression-free survival without the use of radiation. Long-term survival and, in selected cases, even a cure are possible in primary nervous system lymphoma. Treatment should be provided in specialized multidisciplinary centers. In spite of remarkable progress through methotrexate-based chemotherapy, the majority of patients experience relapse within a few years. Better diagnostic tools are required for earlier diagnosis and monitoring of treatment response. A deeper understanding of the pathogenesis of primary nervous system lymphoma may reveal new therapeutic targets.

Primary testicular and intraocular lymphomas: two case reports and a review of the literature

Testicular lymphoma is a rare neoplasm of the testis that is most commonly seen in older patients. It metastasizes preferentially to extranodal sites, including the skin, central nervous system, Waldeyer ring, contralateral testis, and lung. Two case reports of patients with a history of testicular lymphoma who developed involvement of the vitreous and retina are presented. These are interesting cases as the testis, central nervous system, and eye are all immune privileged organs, which may account for occurrence of disease in these sites. Histopathologic examination of diagnostic vitrectomy specimens from both cases showed atypical lymphoid cells with immunoglobulin heavy chain (IgH) gene rearrangements, consistent with the diagnosis of intraocular B-cell lymphoma. The results of a literature review of all reports of ocular involvement with testicular lymphoma are discussed. Patients with testicular lymphoma are at risk for relapse, particularly in the central nervous system. Clinicians should be suspicious for intraocular lymphoma in patients with a history of testicular lymphoma who present with vitritis or retinal lesions.

Pathology and genetics of primary central nervous system and intraocular lymphoma

Ongoing studies based on gene expression profile analysis using microarrays have provided preliminary evidence for significant molecular distinctions between primary central nervous system lymphoma (PCNSL) and nodal lymphomas of the large B-cell type. The application of array-based comparative genomic hybridization techniques attempts to identify genomic distinctions between PCNSL and nodal lymphomas and to identify the molecular markers that relate to prognosis. It is possible that insights gained from these studies will facilitate the development of targeted therapies, which address the fundamental genetic mutations that drive PCNSL and intraocular lymphoma growth.

Analysis of clonal immunoglobulin heavy chain rearrangements in ocular lymphoma

BACKGROUND

The morphologic diagnosis of primary and metastatic intraocular lymphoma (IOL) was made difficult by the paucicellular specimens with fragile populations of lymphocytes retrieved through pars plana vitrectomy (PPV). The analysis of immunoglobulin heavy chain (IgH) gene rearrangements (AIGHR) was used as an adjunct to cytopathology and flow cytometry in systemic lymphoma. In IOL, the sensitivity and specificity of AIGHR are unknown.

METHODS

The authors reviewed the clinical records of patients who underwent PPV for suspicion of IOL at the Immunology and Uveitis Service of the Massachusetts Eye and Ear Infirmary (Boston, MA) between 2000 and 2002. AIGHR was performed as a routine diagnostic test on cell lysates isolated from < 0.5 mL of vitreous fluid. The authors used seminested polymerase chain reaction (PCR) with consensus primers for the VDJ-region of the IgH gene. PCR products were analyzed by polyacrylamide gel electrophoresis.

RESULTS

Thirty patients (37 specimens) with chronic vitritis and 17 patients (23 specimens) with IOL were included. The specificity of vitreous fluid cytopathology, flow cytometry, and AIGHR was 1.0, and the sensitivity values were 0.24, 0.36, and 0.64, respectively. AIGHR was negative in two patients for whom cytopathology or flow cytometry revealed the diagnosis of lymphoma. Clonal IGHR was found in four specimens classified as negative for lymphoma based on cytopathology and flow cytometry.

CONCLUSIONS

AIGHR supplemented cytopathology and flow cytometry to increase the diagnostic yield in IOL.

Detection of CX3CR1 single nucleotide polymorphism and expression on archived eyes with age-related macular degeneration

There is a significant genetic component in age-related macular degeneration (AMD). CX3CR1, which encodes the fractalkine (chemokine, CX3CL1) receptor, has two single nucleotide polymorphisms (SNPs): V249I and T280M. These SNPs are correlated with other aged-related diseases such as atherosclerosis. We have reported an association of CX3CR1 SNP and AMD. In this study we examined CX3CR1 SNP frequencies and protein expression on archived sections of AMD and normal eyes. We microdissected non-retinal, peripheral retinal and macular cells from archived slides of eyes of AMD patients and normal subjects. CX3CR1 SNP typing was conducted by PCR and restriction fragment length polymorphism analysis. CX3CR1 transcripts from retinal cells were also measured using RT-PCR. CX3CR1 protein expression was evaluated using avidin-biotin complex immunohistochemistry. We successfully extracted DNA from 32/40 AMD cases and 2/2 normal eyes. Among the 32 AMD cases, 18 had neovascular AMD and 14 had non-neovascular AMD. The M280 allele was detected in 19/64 (32 cases x2) with a frequency of 29.7%, which was significantly higher as compared to the frequency in the normal population (11.2%). We detected CX3CR1 expression in the various retinal cells. CX3CR1 transcript and protein levels were diminished in the macular lesions. This study successfully analyzed CX3CR1 SNP and transcript expression in microdissected cells from archived paraffin fixed slides. Our data suggest that the M280 allele, a SNP resulting in aberrant CX3CR1 and CX3CL1 interaction, as well as lowered expression of macular CX3CR1, may contribute to the development of AMD.

Diagnosis and Management of Primary Intraocular Lymphoma

Primary intraocular lymphoma (PIOL) is a subset of primary central nervous system lymphoma. The incidence of PIOL has increased in the past 20 years. PIOL often presents as chronic uveitis that is resistant to corticosteroid therapy. Diagnosing PIOL can be challenging and requires an expert pathologist. The treatment of PIOL is difficult because of its high recurrence rate and refractory nature. The objective for the future is to improve diagnostic techniques and therapeutic success while minimizing ocular toxicities.

Helicobacter pylori (H. pylori) molecular signature in conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma

Conjunctival mucosa-associated lymphoid tissue (MALT) lymphoma is an extranodal marginal zone B-cell lymphoma that is characterized by an exaggerated clonal expansion of B cells, which implicate a pathological proliferative response to antigen(s) including bacteria. Helicobacter pylori (H. pylori) infection is recognized as one of the causative agents of gastric MALT lymphoma; however, it has not been reported in extra gastric MALT lymphoma. We studied 5 patients (4 adults and 1 child) with salmon-colored conjunctival lesions. One patient also had a history of abnormal bone marrow biopsy a year earlier with lymphoid aggregates involving 5% of the overall bone marrow. The conjunctival lesions of the 5 patients were biopsied. Histopathological diagnoses were consistent with conjunctival MALT lymphoma. Lymphoma and normal conjunctival cells were microdissected using laser capture microscopy or manual techniques. DNA was extracted and subjected to PCR amplification using H. pylori gene-specific primers from the urease B and vac/m2 gene. Cells from chronic conjunctivitis (normal lymphocytes), conjunctival human T-cell lymphotropic virus type-1/adult T-cell leukemia/lymphoma (HTLV-1/ATL), and orbital B-cell lymphoma were also microdissected, processed and analyzed. PCR amplification and Southern blot hybridization demonstrated H. pylori DNA in the conjunctival MALT lymphoma cells of 4/5 cases. The negative case was the one with a history of abnormal bone marrow. In contrast, H. pylori gene was not detected in normal conjunctival cells from the cases of MALT lymphoma or the lymphocytes, ATL and orbital B-lymphoma cells from the controls. These data suggest that H. pylori may play a role in conjunctival MALT lymphoma.

Primary intraocular lymphoma: a review of the clinical, histopathological and molecular biological features

INTRODUCTION

Primary intraocular lymphoma (PIOL) is a rare non-Hodgkin lymphoma which arises in the retina or the vitreous. It can occur either together with or independently of primary cerebral nervous system lymphoma (PCNSL); the incidence of the latter has significantly increased over the past three decades. PIOL remains one of the most difficult diagnoses to establish, particularly due to its ability to mimic other diseases in the eye and to the limited material which is often available for examination.

METHODS

The article reviews the clinical, histopathological, molecular biological and biochemical approaches to the diagnosis of PIOL. The differential diagnoses, including other lymphomatous manifestations in the eye, e.g. primary uveal lymphoma, as well as non-neoplastic uveal diseases are addressed. Furthermore, the treatment strategies for PIOL are summarised.

RESULTS

Diagnostic progress has been made in various fields, including flow cytometry and immunocytology, cytokine analysis, and as well as molecular biological analysis of the immunoglobulin heavy and light chains using polymerase chain reaction on both fixed and non-fixed material. The optimal therapy of PIOL remains to be determined: the current trends suggest that combined radiotherapy and chemotherapy, as well as intravitreal chemotherapy, are of value. Novel therapies which may have a role in the future include oral trofosfamide.

CONCLUSION

Our understanding of the pathogenesis of PIOL/PCNSL remains far from complete. Intensified efforts must be made to determine the cell of origin of PIOL, as well as to establish "molecular signatures", which could be used to decrease diagnostic delay. Further studies, possibly prospective ones, are required to establish the optimal therapy for initial and recurrent disease.

Primary intraocular lymphoma: clinical, cytologic, and flow cytometric analysis

PURPOSE

To compare cytologic with flow cytometric results of vitreous biopsy specimens obtained to rule out primary intraocular lymphoma (PIOL).

STUDY DESIGN

Prospective noncomparative case series.

PARTICIPANTS

Patients suspected of having PIOL who underwent vitreous biopsy were evaluated.

METHODS

Patients underwent a standard 3-port vitrectomy and vitreous biopsy to rule out PIOL. Each undiluted specimen was split, and half was prepared for cytologic evaluation with the collodion bag method; the other half was submitted for flow cytometric immunophenotyping (FCI). The diluted specimen was processed as a cell block for cytology.

MAIN OUTCOME MEASURES

Final diagnosis based on cytology and FCI.

RESULTS

Ten of 14 patients had sufficient specimens for both cytologic and FCI evaluation. Three patients had chronic inflammation confirmed by both methods. Six patients had large cell lymphoma identified by both cytology and FCI. Two of those 6 patients initially had insufficient specimen for FCI. One patient had large cell lymphoma diagnosed cytologically that was initially negative for a clonal population by FCI. All lymphomas were B-cell type.

CONCLUSIONS

Cytologic evaluation is an accurate diagnostic technique to evaluate for PIOL. FCI is useful for immunophenotyping PIOL. Multiple biopsies may be required to achieve a diagnosis.

Diagnosis of intraocular lymphoma

PURPOSE

To review current techniques for the diagnosis of intraocular lymphoma.

METHODS

Literature review.

RESULTS

There are a limited number of small case series and case reports reporting the diagnosis of intraocular lymphoma. Limitations in the ability to diagnose lymphoma through cytologic examination of the vitreous has led to investigations into immunohistochemistry either manually or by automated cytofluorography, intraocular cytokine determinations, and polymerase chain reaction of the vitreous or tissue lymphoid cells to detect gene rearrangements in the IgH, bcl-2, or T-cell receptor gamma gene. Data regarding diagnostic efficiency of the various testing strategies is limited by small patient numbers. Careful handling of the vitreous specimen and adequate laboratory and pathological support is critical.

CONCLUSIONS

Despite a proliferation of new techniques for the diagnosis of intraocular lymphoma, none is clearly superior. Use of multiple testing strategies may improve diagnostic yield.

Pseudouveitis: a clue to the diagnosis of primary central nervous system lymphoma in immunocompetent patients

Primary oculocerebral non-Hodgkin lymphoma (NHL) of the immunocompetent patient is associated with significant morbidity and mortality, but early diagnosis and follow-up may improve prognosis. The eye, anatomically and embryologically part of the central nervous system (CNS), can be the primary site of the lymphomatous process. In patients with symptoms of atypical uveitis, vitrectomy can be of great help for early diagnosis of primary central nervous system lymphoma. We retrospectively reviewed the diagnostic features, treatment, and evolution of 10 patients with primary central nervous system lymphoma who presented with symptoms of pseudouveitis. The patients complained of chronic vitreal opacities, increasing with time. These symptoms contrasted with the absence of the usual signs of inflammation of the anterior segment or of the retina, which characterize true uveitis. Vitrectomy was proposed after lumbar puncture and cerebral magnetic resonance imaging. Six vitrectomies were carried out, 3 patients had a stereotaxic biopsy, and 1 patient had a cardiac biopsy. A pathologic diagnosis of large B-cell lymphoma was made on vitrectomy specimens in 100% of the patients who had this procedure. The mean time from onset of ocular symptoms to diagnosis was 24 months. This series was characterized by a rare systemic dissemination of the NHL (negative in 80%), a strong preponderance of B-cell NHL, and the absence of association with Epstein-Barr virus (EBV) among these immunocompetent patients. To our knowledge, this series includes the only reported case of oculocardiac lymphoma. Meningeal dissemination appeared to be associated with a poor prognosis. Neurologic complications of treatment combining radiotherapy and methotrexate were significant among patients older than 60 years of age. The current study suggests that primary central nervous system lymphoma should be suspected in patients with pseudouveitis, and that the diagnosis can be established quickly and without side effects by vitrectomy. These patients should be followed carefully in order to detect meningeal dissemination.

Biological diagnosis of primary intraocular lymphoma

Primary intraocular lymphoma (PIOL) is a rare presentation of lymphoma that is particularly difficult to recognize. In our institution, 36 cases of PIOL were diagnosed between March 1997 and July 2002. The recognition of lymphoma cells by cytology with or without immunophenotyping on slides generated a strong suspicion of the diagnosis in 34 of 36 cases. The diagnosis was confirmed by measurement of interleukin-10 (IL-10) in the vitreous humour or aqueous humour; high levels were observed in 35 of 36 cases, all were of B-cell origin. As expected, the only case with T-cell lymphoma had a very low level of IL-10. Furthermore, IL-10 levels excluded this diagnosis in two cases that were incorrectly suspected of PIOL after cytological examination. Finally, detection of clonality by polymerase chain reaction techniques, performed in 29 cases, represented a helpful tool in diagnosing PIOL as this approach definitively confirmed the diagnosis of B- or T-cell lymphoma in 17 cases.

Microdissection combined with the polymerase chain reaction to identify potentiating viral co-infection in patients with HIV/AIDS with ocular infection

BACKGROUND

In the presence of several coexisting infections, superimposed tissue necrosis or tissue metaplasia, it may be difficult to recognize standard histologic morphology on hematoxylin-eosin slides. Tissue microdissection combined with the polymerase chain reaction (PCR-MD) offers the advantages of high specificity and relative speed. The objective of this study was to describe the use of PCR-MD in identifying potentiating viral co-infection in patients with HIV/AIDS with retinitis and choroiditis.

METHODS

Eyes from two patients with HIV/AIDS with several ocular infections were studied by a variety of techniques, including standard histologic examination, immunochemistry, electron microscopy and in situ hybridization. PCR-MD was used to identify coexisting viral infections.

RESULTS

Histologic examination showed cytomegalovirus retinitis in both cases. Use of PCR-MD allowed the identification of Epstein-Barr virus within a zone of fulminant varicella-zoster virus retinitis in one patient. PCR-MD confirmed the presence of human herpesvirus 8 in the second patient, who had ocular lymphoma.

INTERPRETATION

PCR-MD can be used to demonstrate coexisting viral infection in ocular specimens from patients with unusually fulminant courses. Co-infections may contribute to the observed clinical course and should be considered in patients with rapid progression or unusual presentation.

Applications of polymerase chain reaction in rheumatology

Polymerase chain reaction (PCR) is a highly sensitive and specific method for detection and quantification of specific nucleic acids from a clinical sample. With its use, genetic, infectious, neoplastic, and autoimmune diseases can be diagnosed and managed with a high level of sensitivity, accuracy, and rapidity. This technique exactly reproduces unlimited copies of DNA, even if only a small amount are present initially. PCR assays can detect presence of fastidious and slow-growing microorganisms, such as chlamydia, mycoplasmas, mycobacterias, and viruses directly from clinical specimens and also can detect antimicrobial resistance. The value of viral load measurement by nucleic acid amplification in the management of patients with HIV infection or hepatitis C has also been well established. From the point of view of a clinician, the applications of PCR are focused mainly in the amplification and detection of diagnostic DNA segments from the genomes of both pathogens and patients.

Expression of chemokine receptors, CXCR4 and CXCR5, and chemokines, BLC and SDF-1, in the eyes of patients with primary intraocular lymphoma

OBJECTIVE

Chemokines have a range of biologic activities, including regulation of leukocyte trafficking, modulation of hematopoietic cell proliferation, and adhesion to extracellular matrix molecules. Specifically, B-lymphocyte chemoattractant (BLC); BCA-1; CXCL13, SCYB13) and stromal cell-derived factor-1 (SDF-1, CXCL12, SCYB12) are chemotactic for human B cells, and their ligands CXCR4 and CXCR5 are differentially expressed on B cells, including malignant B cells. We investigated the expression of these chemokine/chemokine receptors in eyes with primary intraocular B-cell lymphoma (PIOL).

DESIGN

Observational case series (human tissue study).

METHODS

Three freshly enucleated eyes with PIOL and a normal autopsied eye were frozen and sectioned. The sections were evaluated using immunohistochemistry (avidin-biotin-complex immunoperoxidase technique) for CXCR4, CXCR5, BLC, and SDF-1 to detect the expression and location. Reverse transcriptase-polymerase chain reaction was used to detect chemokine transcripts of CXCR4, CXCR5, BLC, and SDF-1 in PIOL and retinal pigment epithelium (RPE) cells after microdissection-either by laser capture (Arcturus) or by manual dissection-from frozen sections.

MAIN OUTCOME MEASURES AND RESULTS

The three PIOL eyes showed similar pathology, with typical diffuse large B-lymphoma cells subjacent to the RPE. The eyes also demonstrated a similar chemokine profile. High expression levels of CXCR4 and CXCR5 were found limited to the lymphoma cells. In contrast, BLC protein was expressed in the RPE but not located in other ocular resident cells. SDF-1 was barely detected in a few RPE cells. CXCR4 and CXCR5 transcripts were detected abundantly in lymphoma cells, whereas BLC and SDF-1 transcripts were detected only in the RPE and not the malignant cells. No chemokine expression was detected on the RPE cells in the normal control eye.

CONCLUSIONS

Chemokines and chemokine receptors selective for B cells were identified in RPE and malignant B cells, respectively. BLC, and possibly SDF-1, attracts both normal and malignant B-cells while promoting migration of only small numbers of T cells and macrophages. We propose that B-cell chemokines may be involved in the pathogenesis of PIOL by selectively attracting lymphoma cells to the RPE from the choroidal circulation. Our data suggest that inhibition of B-cell chemoattractants could be a future strategy for the treatment of PIOL.

Intraocular lymphoma

There are two distinct forms of intraocular lymphoma. One originates within the central nervous system (CNS) and is called primary CNS lymphoma. The second form arises outside the CNS and metastasizes to the eye. When primary CNS lymphoma initially involves the retina, it is named primary intraocular lymphoma (PIOL). Although PIOL is a rare malignancy, the incidence has dramatically increased in the past 15 years. Typical clinical manifestations include blurred vision and floaters. Ophthalmic examination reveals vitreitis and subretinal infiltrates. Diagnosis of PIOL can be difficult and requires neuroimaging, examination of the cerebrospinal fluid and/or vitreous. Molecular analysis detecting immunoglobulin gene rearrangements and ocular cytokine levels showing elevated interleukin (IL)-10 with an IL-10 to IL-6 greater than 1.0 are helpful adjuncts for the diagnosis. Treatment includes systemic chemotherapy and radiation with current regimens favoring the use of chemotherapy first. In contrast, metastatic systemic lymphoma, like other metastatic ocular tumors, is usually confined to the uvea, in particular the choroid. Compared with PIOL, metastatic systemic lymphomas have a much lower prevalence, better prognosis, and are less likely to create a diagnostic dilemma.

Neoplastic masquerade syndromes

Masquerade syndromes are classically defined as entities which emulate inflammatory conditions but which are in fact due to a neoplastic process. Careful history and examination in concert with appropriate ancillary investigations and histopathologic evaluation of tissue specimens are required in order to make the correct diagnosis. Many conditions may result in an appearance mimicking an inflammatory condition. The authors review neoplastic conditions which may be considered masquerades. The most common of these is primary intraocular lymphoma or primary central nervous system lymphoma, occurring predominately in older individuals. Diagnostic strategies, therapy, and prognosis are reviewed in detail. Other conditions that can be considered masquerade syndromes are reviewed as well, including lymphomatous and nonlymphomatous conditions, such as melanoma, retinoblastoma, juvenile xanthogranuloma, metastatic lesions, and paraneoplastic syndromes, among others.

Fluorescein angiographic findings in primary intraocular lymphoma

PURPOSE

Primary intraocular lymphoma (PIOL), also known as primary central nervous system lymphoma, is a rare yet blinding and fatal disease. Often presenting with ocular involvement, it can masquerade as posterior or intermediate uveitis, thus delaying diagnosis. A noninvasive ancillary test such as fluorescein angiography could be helpful in raising the level of suspicion in the diagnosis of this disease.

METHODS

Results of fluorescein angiography (FA) and clinical characteristics of 17 patients (31 eyes) who presented to the National Eye Institute with the diagnosis of PIOL (confirmed by histopathologic analysis) were reviewed.

RESULTS

The most common angiographic characteristics included disturbances at the level of the retinal pigment epithelium (RPE), such as granularity (19 eyes [61%]), blockage (17 eyes [55%]), and late staining (14 eyes [45%]). These changes are well correlated to histopathologic findings of lymphoma cells located between the RPE and Bruchs membrane. Perivascular staining or leakage and cystoid macular edema were rare. Other less common findings included pigment epithelial detachments and punctate hyperfluorescent lesions. Clinical characteristics found in eyes for which results of FA were available included vitreitis (29 eyes [94%]), subretinal infiltrates (19 eyes [61%]), and anterior chamber cells (10 eyes [32%]). In some cases, clinical examination did not correlate with FA findings.

CONCLUSIONS

Although PIOL may present with a normal angiographic phenotype, extensive RPE changes demonstrated by FA, combined with the absence of perivascular staining or leakage and macular edema, may be associated with and distinctive of PIOL.

Applications of the polymerase chain reaction to diagnosis of ophthalmic disease

The polymerase chain reaction (PCR) is a powerful molecular biologic technique for the analysis of very small amounts of DNA. This technique has found increasing use in the past 10 years for the detection of pathogenic organisms associated with many forms of ocular inflammatory and infectious disease. PCR has shown utility in the diagnosis of viral uveitis, infectious endophthalmitis, and parasitic eye disease. The strengths and weaknesses of this diagnostic technique are discussed. Additionally, uses of PCR in linking known pathogens to disease, and to discovering novel pathogens, are addressed.

Detection of Toxoplasma gondii DNA in primary intraocular B-cell lymphoma

Primary intraocular lymphoma, a variant of primary central nervous system lymphoma with ocular involvement, is a large B-cell non-Hodgkin's lymphoma. Some cases of primary intraocular lymphoma have been reported to be associated with microorganisms including Epstein-Barr virus (EBV) and human herpes virus-8 (HHV-8), but not parasites. We analyzed 10 cases of primary intraocular lymphoma using microdissection and PCR. Tumor and normal cells were microdissected from ocular tissue on slides and subjected to PCR for genes from Toxoplasma gondii, EBV, and HHV-8. We detected Toxoplasma gondii, not HHV-8 or EBV, DNA in the lymphoma but not in normal cells of two cases that resembled ocular toxoplasmosis clinically. We speculate that Toxoplasma gondii may play a role in some forms of primary intraocular B-cell lymphoma.

Ocular manifestations of central nervous system lymphoma

Primary intraocular lymphoma (PIOL) is a variant of primary central nervous system lymphoma in which lymphoma cells are initially present only in the eyes without evidence of disease in the brain or cerebrospinal fluid. Patients with PIOL are typically older adults who present with blurred vision and floaters. The ophthalmic examination characteristically shows a cellular infiltrate in the vitreous with or without the presence of subretinal infiltrates. Diagnostic evaluation for PIOL includes neuroimaging, cytologic examination of the cerebrospinal fluid, and a diagnostic vitrectomy with special handling of the vitreous specimen, if the former is nondiagnostic. Molecular and cytokine analyses are useful adjuncts to cytology for the diagnosis of PIOL. Recent molecular studies demonstrating viral DNA in the ocular lymphoma cells suggest a role for infectious agents in the pathogenesis of PIOL. To date, the best mode for treatment of PIOL or recurrent primary central nervous system lymphoma involving only the eyes remains undefined.

Vitrectomy in the management of uveitis

OBJECTIVE

To review the indications for vitrectomy in uveitis cases.

PATIENTS AND METHODS

Charts of patients seen at the uveitis clinic of the Jules Gonin Eye Hospital from January 1993 to August 1998 and who had undergone vitrectomy were reviewed. Patients with infectious uveitis occurring within three months after intraocular cataract surgery were excluded. The types of uveitis were recorded and indications for vitrectomy were analyzed.

RESULTS

A total of 630 patients were examined at the uveitis clinic. Fifty-one of these patients (51 eyes, 8.1%) were referred for vitrectomy and were included in this study. Vitrectomy was performed for three reasons: 1) to treat the complications of uveitis (90%), including vitreous opacification in 35 eyes (69%), retinal detachment in seven eyes (14%), epimacular membrane in seven eyes (14%), and dense opacification of the posterior capsule after cataract surgery in six eyes (12%)(the mean delay between uveitis and vitrectomy in this group was 8.4 years); 2) for diagnostic purposes in 19 eyes (37%); and 3) to remove confined infectious foci in 16 eyes (31%) and allow a thorough intraocular distribution of antibiotics. Visual acuity improved in 41 patients (80.4%), remained unchanged in three (5.8%), and decreased in seven (13.7%) because of secondary or persistent retinal detachment or cystoid macular edema.

CONCLUSION

Vitrectomy was indicated to treat the complications of uveitis, to provide vitreous for diagnostic purposes, and to allow a better diffusion of intraocular antibiotics. Long-standing uveitis did not seem to be influenced by vitrectomy.

Systemic non-Hodgkin's lymphoma presenting as a serpiginous choroidopathy: report of a case and review of the literature

Intraocular lymphoma is a rare tumour, the two main types being primary central nervous system non-Hodgkin's lymphoma (CNS-NHL) and, less commonly, systemic lymphoma that has spread to involve the eye. We present a case of a systemic NHL resulting in a serpiginous choroidopathy. To our knowledge, this presentation has not previously been reported. The diagnosis of this case was made based on the temporal relationship between the clinical activity of the choroidopathy and its response to chemotherapy. Diagnosis of intraocular lymphoma on vitreous biopsy is notoriously difficult, and this case is presented along with a review of the literature regarding vitreous biopsy and diagnostic techniques.

Iris involvement in primary intraocular lymphoma: report of two cases and review of the literature

Non-Hodgkin's lymphoma involves ocular tissues either as a primary tumor or as secondary metastasis from systemic disease. Diagnosis is based on the identification of malignant cells in the eye by biopsy. Although primary intraocular lymphoma cells have been identified in the optic nerve, ciliary body, and iris of a small number of patients by histopathology, these sites of infiltration have rarely been observed on clinical examination. We studied clinical and histopathological findings of two patients with iris infiltration by primary intraocular lymphoma and reviewed the findings of 163 cases reported in the literature.

Rearrangement of immunoglobulin gene in metastatic Waldenström macroglobulinemia to the vitreous

PURPOSE

To report metastatic Waldenström macroglobulinemia cells with immunoglobulin heavy chain gene rearrangement in the vitreous and the blood.

METHODS

A 58-year-old man with Waldenström macroglobulinemia developed bilateral vitreitis. Diagnostic vitrectomy was performed on the left eye. The vitreous cells and the peripheral blood lymphocytes were analyzed using microdissection and polymerase chain reaction amplification.

RESULTS

Vitrectomy specimen of the left eye contained a few degenerated cells. Molecular analysis showed immunoglobulin heavy chain gene rearrangement at the third complementary determining region of the vitreal infiltrating cells and peripheral blood lymphocytes.

CONCLUSIONS

Waldenström macroglobulinemia rarely metastasizes to the vitreous. Molecular detection of the immunoglobulin heavy chain gene third complementary determining region rearrangement is helpful in the diagnosis of the malignancy. Microdissection combined with polymerase chain reaction is a useful and innovative tool for molecular pathological investigation.

Elevated vitreous interleukin-10 level is not diagnostic of intraocular-central nervous system lymphoma

OBJECTIVE

Diagnosis of intraocular-central nervous system (CNS) lymphoma is commonly made by identifying malignant lymphocytes in the vitreous. However, such cells are in the minority in the vitreous cellular infiltrate (most are reactive lymphocytes), and therefore lack of cytologic support from biopsied vitreous samples in patients suspected of having intraocular-CNS lymphoma may occur. Recent data suggest that interleukin-10 (IL-10) levels are elevated in the serum and vitreous of patients with non-Hodgkin's lymphoma, whereas IL-12 and IL-6 levels are elevated in patients with uveitis of non-neoplastic etiology. The authors evaluated the usefulness of measuring vitreous levels of IL-6, -10, and -12 in the diagnosis of intraocular-CNS lymphoma.

DESIGN

Prospective case series.

PARTICIPANTS

Seventeen patients with intraocular inflammation who underwent a diagnostic or therapeutic vitrectomy: 4 patients with intraocular-CNS lymphoma and 13 patients with uveitis unrelated to a neoplasm.

INTERVENTION

Eighteen vitreous specimens were obtained prospectively. Concentrations of IL-6, -10, and -12 were measured by enzyme immunosorbent assay, and relative ratios of the interleukins were calculated. Cytopathologic examination and flow cytometry of vitreous cells were also performed.

MAIN OUTCOME MEASURES

The ratio of IL-10/IL-12 and IL-10/IL-6 was calculated to assess any association of intraocular-CNS lymphoma and high vitreous IL-10 relative to IL-6 and IL-12 levels.

RESULTS

The IL-10/IL-6 and IL-10/IL-12 ratio was greater than 1 in 8 of 14 vitreous specimens obtained from 13 patients with non-neoplastic uveitis. One of the four specimens from patients with cytologically proven intraocular-CNS lymphoma had vitreous IL-10/IL-6 and IL-10/IL-12 ratios of less than 1.

CONCLUSION

Although a helpful diagnostic tool, an elevated vitreous IL-10 to IL-6 or IL-12 ratio is not always associated with intraocular-CNS lymphoma.