Classification, pathogenesis and molecular pathology of primary CNS lymphomas

Stat3-positive tumor cells contribute to vessels neoformation in primary central nervous system lymphoma

With the aim of elucidating the relationship between Stat3 expression and tumor vessels abnormalities in the PCNLs, in this study we evaluated Stat3 and pStat3 expression by Real-time PCR and by immunohistochemistry in biopsy sections from PCNSL patients. Correlations of the expression levels with the presence of aberrant vessels were analyzed by confocal laser microscopy analysis, using FVIII as endothelial cell marker, CD133 and nestin as cancer stem cell (CSC) marker, CD20 as tumor cell marker, and Stat3. In addition, we investigated Stat3 mutations in lymphoma cells to clarify the role of the constitutive expression of Stat3 and of its phosphorylated forms. Results showed that in PCNSL, putative endothelial cells lining the vessels are heterogeneous, expressing FVIII/ pStat3/CD133 (presumably originally they are vascular progenitor cells), as well as FVIII/CD20/CD133 (presumably originally they are tumor cells). Finally, we detected a fraction of the FVIII⁺ endothelial cell that co-expressed Stat3 bearing a tetraploid karyotype, while no amplification signal for the Stat3 gene was detected.

Diagnostic Vitrectomy (25-Gauge) in a Case with Intraocular Lymphoma Masquerading as Bilateral Granulomatous Panuveitis

Purpose.

To report a case of intraocular lymphoma, masquerading as bilateral granulomatous panuveitis, and diagnosed after harvesting vitreous specimen with a 25-gauge vitrectomy instrument.

Methods.

A 67-year-old woman presented with bilateral granulomatous uveitis. Visual acuity in both eyes was severely impaired because of severe concurrent cataract and vitreous organization. Sutureless phacoemulsification and posterior chamber intraocular lens implantation combined with 25-gauge diagnostic vitrectomy was performed.

Results.

Cytopathology and immunocytochemistry of the vitreous disclosed a non-Hodgkin B-cell lymphoma despite unremarkable brain MRI, lumbar puncture, bone marrow aspiration, and whole body scan. Visual acuity improved to 20/120 in both eyes.

Conclusions.

Sutureless combined 25-gauge diagnostic vitrectomy, phacoemulsification, and posterior chamber intraocular lens implantation during one-stage surgery was effective in obtaining appropriate vitreous material for cytology in a case of intraocular lymphoma.

The role of additional radiotherapy for primary central nervous system lymphoma

BACKGROUND

Prior to the introduction of the chemotherapeutic agent methotrexate, radiotherapy was the sole, first-line option for the treatment of individuals with primary central nervous system lymphoma (PCNSL), Now that methotrexate is available, the role of radiotherapy in the treatment of PCNSL has been called into question. Although various studies suggest promising results with regard to overall and progression-free survival with the use of chemotherapeutic regimens alone as well as in combination with radiotherapy, no evidence-based standard regimen has yet been defined.

OBJECTIVES

The objective of this review was to assess and summarise the evidence available regarding the efficacy and tolerability of radiotherapy in addition to chemotherapy in the treatment of immunocompetent individuals with PCNSL.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (issue 01.2014), MEDLINE from January 1950 to February 2014 and conference proceedings from 2005 to 2013. 

SELECTION CRITERIA

We included randomised controlled trials (RCTs) comparing chemotherapy plus radiotherapy with chemotherapy alone in individuals with PCNSL. Outcomes defined in this review were overall survival, progression-free survival, response to treatment, adverse events, treatment related mortality and quality of life. We excluded trials in which the chemotherapy regimen differed between treatment arms, trials in which fewer than 80% of participants had PCNSL or those recruiting immunocompromised individuals with PCNSL.

DATA COLLECTION AND ANALYSIS

Two review authors independently screened the results of the search strategies for eligibility for this review. Both assessed risk of bias. Where relevant data was unavailable, we contacted the investigator by email.

MAIN RESULTS

Of the 556 potentially relevant studies only two met the inclusion criteria. One of those was excluded as the trial was abandoned prematurely and reported only preliminary results. The only analysed trial enrolled 551 participants receiving first-line chemotherapy (methotrexate) followed by whole brain radiotherapy (WBR) or receiving chemotherapy only (methotrexate followed by cytarabine in case of incomplete response). In this non-inferiority trial, the intention-to-treat (ITT) population consisted of 411 participants and the per-protocol (PP) population of 318 participants. We judged the potential for risk of bias in this open-label study as moderate.The estimated effect of chemotherapy plus WBR on survival was similar to that with chemotherapy alone but due to a wide CI we could not rule out the superiority of either therapy. This applied to both the ITT population (HR 1.01, 95% CI 0.79 to 1.30; P = 0.94) and the PP population (HR 1.06, 95% CI 0.80 to 1.40; P = 0.71) (moderate-quality evidence). Due to the low number of participants and a risk of detection bias we found low-quality evidence for an improvement in progression-free survival in participants in the ITT population receiving WBR in addition to chemotherapy (HR 0.79, 95% CI 0.63 to 0.99; P = 0.041). An improvement in PFS was also observed with WBR plus chemotherapy in participants in the PP population, but the CI was slightly wider and the result not significant (HR 0.82,95% CI 0.64 to 1.07; P = 0.14). Treatment-related mortality and health-related quality of life were not evaluated. Treatment-related neurotoxicity was assessed clinically in 79 participants, revealing signs of neurotoxicity in 49% of those receiving chemotherapy plus radiotherapy and in 26% of those receiving chemotherapy only (RR 1.85, 95% CI 0.98 to 3.48; P = 0.054) (very-low-quality evidence).

AUTHORS' CONCLUSIONS

In summary, the currently available evidence (one RCT) is not sufficient to conclude that WBR plus chemotherapy and chemotherapy alone have similar effects on overall survival in people with PCNSL. The findings suggest that the addition of radiotherapy (WBR) to chemotherapy may increase progression-free survival, but may also increase the incidence of neurotoxicity compared to chemotherapy only (methotrexate monotherapy). As the role of chemoradiotherapy in the treatment of PCNSL remains unclear, further prospective, randomised trials are needed before definitive conclusions can be drawn.

Primary cerebral low-grade B-cell lymphoma, monoclonal immunoglobulin deposition disease, cerebral light chain deposition disease and "aggregoma": an update on classification and diagnosis

Background

This work aims to add evidence and provide an update on the classification and diagnosis of monoclonal immunoglobulin deposition disease (MIDD) and primary central nervous system low-grade lymphomas. MIDD is characterized by the deposition of light and heavy chain proteins. Depending on the spatial arrangement of the secreted proteins, light chain-derived amyloidosis (AL) can be distinguished from non-amyloid light chain deposition disease (LCDD). We present a case of an extremely rare tumoral presentation of LCDD (aggregoma) and review the 3 previously published LCDD cases and discuss their presentation with respect to AL.

Case presentation

A 61-year-old woman presented with a 3½-year history of neurologic symptoms due to a progressive white matter lesion of the left subcortical parieto-insular lobe and basal ganglia. 2 former stereotactic biopsies conducted at different hospitals revealed no evidence of malignancy or inflammation; thus, no therapy had been initiated. After performing physiological and functional magnetic resonance imaging (MRI), the tumor was removed under intraoperative monitoring at our department. Histological analysis revealed large amorphous deposits and small islands of lymphoid cells.

Conclusion

LCCD is a very rare and obscure manifestation of primary central nervous system low-grade lymphomas that can be easily misdiagnosed by stereotactic biopsy sampling. If stereotactic biopsy does not reveal a definite result, a “wait-and-see” strategy can delay possible therapy for this disease. The impact of surgical removal, radiotherapy and chemotherapy in LCDD obviously remains controversial because of the low number of relevant cases.

Secondary orbital and intraocular lymphoma treated with immunochemotherapy

PURPOSE

To assess ocular and orbital structure by ocular echography and magnetic resonance imaging, fluoroangiography, indocyanine green angiography, and optical coherence tomography before and after therapy with rituximab (Mabthera) and chlorambucil in a patient with concurrent intraorbital and intraocular lymphoma and diplopia.

METHODS

A 69-year-old man referred blurred vision and proptosis in his left eye associated with diplopia. Best-corrected visual acuity was 0.3 logarithm of the minimum angle of resolution in the left eye and 0.02 logarithm of the minimum angle of resolution in the right eye. Ocular echography and magnetic resonance imaging revealed the presence of concurrent orbital and intraocular tumor, and a B-cell lymphocytic lymphoma was diagnosed by incisional biopsy. The patient was treated with the oral alkylating agent chlorambucil and with intravenous infusions of the monoclonal anti-CD20 antibody rituximab (Mabthera) and evaluated with visual acuity, echography, fluoroangiography, indocyanine green angiography, and magnetic resonance imaging.

RESULTS

After combined immunochemotherapy with rituximab/chlorambucil, the patient showed in the left eye a significant improvement of visual acuity (0.1 logarithm of the minimum angle of resolution) and a disappearance of diplopia at the end of follow-up.

CONCLUSION

In this case report, combined systemic therapy with chlorambucil and rituximab was effective to reduce and control orbital and intraocular lymphoma.

Retrospective cytological study of intraocular lymphoma using vitreous and intraocular perfusion fluid

Intraocular lymphoma (IOL) is an extremely rare tumor. We carried out a retrospective cytopathological study with vitreous and intraocular perfusion fluid obtained on conducting a pars plana vitrectomy in 18 cases of IOL. In the 18 cases, nine were patients of Kansai Medical University Takii Hospital from 1991 to 2007, and the other nine had already been reported by other hospitals. Most patients were male, and the average age at onset was 60.4-year-old. The main symptoms were vitreous opacity, amblyopia, and blurred vision. Cases of primary intraocular lymphoma numbered 8/15 (53%), while cases of infiltration of malignant lymphoma from the brain numbered 2/15 (13%). Although IOL contains various subtypes of lymphoma, the most frequent subtype is diffuse large B-cell type lymphoma. It has been reported that making a definite diagnosis of IOL is difficult because the clinical symptoms and examinations are similar to chronic uveitis, and so IOL is called "masquerade syndrome." Recently, serological and molecular pathological studies have been carried out in addition to morphological examination. However, a cytological diagnosis based on the clinical background and/or image findings is important for the diagnosis of IOL, because of the volume limit of the vitreous fluid and difficulty of obtaining specimens from the inside of the eyes.

Aquaporin-4 expression in primary human central nervous system lymphomas correlates with tumour cell proliferation and phenotypic heterogeneity of the vessel wall

No literature data are available concerning the expression of aquaporin-4 in primary central nervous system lymphomas and the relationship between aquaporin-4 expression and the morphological characteristics of blood vessels. Here, we have investigated this relationship in 24 human diffuse large B-cell primary central nervous system lymphomas by means of immunocytochemistry and confocal laser microscopy. Results have shown that: (i) a high aquaporin-4 expression correlated with a high Ki-67 index and aquaporin-4 marked tumour and endothelial cells in cytoplasm and plasma membranes, while aquaporin-4 expression was low in tumour areas with a low Ki-67 index where few tumour cells were positive to aquaporin-4, and endothelial cells showed aquaporin-4 expression on their abluminal side. (ii) Different type of cells participated in vessels formation: CD20(+) tumour cells and factor VIII(+) endothelial cells; aquaporin-4(+) tumour cells and CD31(+) endothelial cells; CD20(+) and aquaporin-4(+) tumour cells; glial fibrillary acidid protein(+) endothelial cells surrounded by glial fibrillary acidic protein(+) tumour cells. Overall, these data suggest the importance of aquaporin-4 in primary central nervous system lymphomas due to its involvement in cerebral oedema formation and resolution and tumour cell migratory activity, and have documented that tumour microvasculature in lymphomas is extremely heterogeneous, confirming the importance of neoangiogenesis in the pathogenesis of lymphomas.

Primary pituitary lymphoma in an immunocompetent patient: a rare clinical entity

Primary pituitary lymphoma in immunocompetent patients is an exceedingly rare clinical entity. We report the case of a 41-year-old woman with initial polydipsia and polyuria. When laboratory evaluation revealed panhypopituitarism, a pituitary enhanced MRI was performed and was suggestive of a pituitary adenoma. Obstructive hydrocephalus provoked by enlarged sellar mass was also demonstrated during observation, and a shunt procedure following lesion resection was carried out. Histopathological examination and immunophenotyping verified diffuse large B-cell non-Hodgkin's lymphoma. No systemic disease was found on staging of the patient. We will also review the clinical, radiological features and outcomes of 28 cases that have been reported since 1993.

B-cell lymphoma line (Raji) viability and surface marker expression minimally affected by 20- and 25-gauge vitrectomy systems analyzed by flow cytometry

PURPOSE

The purpose of this study was to evaluate the effect of 20-gauge (20-G) and 25-gauge (25-G) vitrectomy on cell viability and diagnostic yield (surface marker expression) using flow cytometry and human lymphoma cells in culture.

METHODS

Cultured human Burkitt lymphoma cells (Raji B-cell lymphoma line) were allocated into five study groups in Roswell Park Memorial Institute media. By using manual aspiration, cells were then processed by aspiration alone, by 20-G vitrectomy at 600 cuts per minute (cpm) and 1,500 cpm, or by 25-G vitrectomy at both 600 and 1,500 cpm. To assess cell viability and cell surface marker expression, samples underwent standard flow cytometry analysis for suspected lymphoma using 7-amino-actinomycin D and antibodies against CD45, CD19, lambda, and kappa light chains.

RESULTS

Twenty-five samples were processed after being divided into four vitrectomy groups and one nonvitrectomy group (control). The mean cell viability was 98.5 for both the nonvitrectomized and vitrectomized specimens. The percentage of cells positive for CD45 or kappa light chain was the same in the nonvitrectomized and vitrectomized groups. In addition, the level of expression of these molecules was not significantly different in all five groups. Similarly, no difference was seen for these markers between 20-G and 25-G vitrectomy at either a cut rate of 600 or 1,500 cpm. The percentage positive for CD19 was significantly lower for the 20-G vitrectomy at 1,500 cpm compared with the 25-G vitrectomy at both 600 and 1,500 cpm. Percentage of CD19 cells was greater for the 25-G vitrectomy at 600 cpm than the nonvitrectomy group.

CONCLUSION

Compared with simple aspiration, both 20-G and 25-G vitrectomy seem to have no significant effect on cell viability or diagnostic yield for B-cell lymphoma cells (Raji cell line) in suspension based on flow cytometry. Further studies need to be conducted to study and compare 20-G versus 25-G vitrectomy on lymphoma cells in human vitreous or in an animal model.

Prognostic value of immunohistochemical profile and response to high-dose methotrexate therapy in primary CNS lymphoma

Several biomarkers have been identified as prognostic factors in primary central nervous system lymphoma (PCNSL). However, the correlation between the histogenetic origin of PCNSL and the response to therapy is still unclear. To elucidate the utility of immunophenotypic markers in predicting clinical outcomes, we investigated 27 immunocompetent patients with PCNSL treated with high-dose methotrexate therapy. Of the 27 patients, 25 received whole-brain radiotherapy after high-dose methotrexate. Immunostaining for CD5, CD10, BCL-6, and MUM-1 was used to determine the immunophenotypic profile of diffuse large B-cell lymphoma of PCNSL. We then evaluated whether immunophenotypic markers were associated with the response to therapy or patients' survival. The response to induction high-dose methotrexate therapy was determined by magnetic resonance imaging after three courses of i.v. high-dose methotrexate. We categorized B-cell lymphomas into three known subtypes: germinal center B-cell (GCB), activated-GCB, and post-GCB subtypes according to immunohistochemical profile. All the BCL-6-positive samples were co-positive for MUM-1 and therefore classified into activated-GCB subtype. BCL-6 expression in this study was associated with poor progression-free survival (P = 0.038). No immunophenotypic markers or subtypes had a significant effect on the response to high-dose methotrexate therapy. However, the response itself was a significant predictor for both progression-free survival (P < 0.001) and overall survival (P = 0.003). Further investigation is needed to assess BCL-6 as a potential prognostic factor in PCNSL.

Primary central nervous system lymphoma: immunohistochemical profile and prognostic significance

Primary central nervous system lymphoma (PCNSL) is a rare subtype of non-Hodgkin lymphoma (NHL) with extranodal location affecting only the CNS, meninges and eye, without visceral or lymph node involvement. Its incidence has increased sharply over the past three decades, especially in immunocompetent subjects. Most PCNSL cases are diffuse large B-cell lymphomas (DLBCLs). However, it differs from nodal DLBCL in that it has a worse prognosis. DLBCLs are a heterogeneous entity and according to new genomic discoveries, classifications into prognostic subgroups have been embarked upon. Two prognostic algorithms were then prepared using a panel of immunohistochemical markers (CD10, Bcl6, MUM1/IRF-4, and Bcl2), thus categorizing DLBCL into two subgroups, GCB (germinal centre B-cell-like) or non-GCB, and into Group 1 or Group 2. Our goal is to apply both of these two sub-classifications to 39 PCNSLs, in order to assess their usefulness and prognostic relevance. 74.3% of our PCNSLs were of a non-GCB phenotype, corresponding to an activated postgerminal origin. They were evenly distributed across G1 and G2. Two- and 5-year overall survival rates were 34.8% and 19.6%, respectively. Younger age (<65) and a therapeutic combination of chemotherapy and radiotherapy significantly improved our patients' survival rates. The other clinical or biological markers tested had no prognostic impact. The two classifications did not reveal any significant survival difference. The recent discovery of a specific "transcriptional signature" of PCNSL, marking them out of DLBCL could account for the irrelevance of such prognostic classifications to PCNSL.

Comparison of 2-Methoxyestradiol and Methotrexate Effects on Non-Hodgkin's B-Cell Lymphoma

PURPOSE

Methotrexate (MTX) is the most commonly used chemotherapeutic agent to treat primary central nervous system lymphoma (PCNSL) and intraocular lymphoma (IOL). 2-methoxyestradiol (2ME2) is a potent antitumor and anti-angiogenesis agent which, unlike other cytotoxic drugs, has minimal toxicity. In this study, anti-proliferative, apoptotic, and cell-cycle effects of 2ME2 and MTX were compared to evaluate 2ME2 efficacy in human lymphoma cells, models for non-Hodgkin B cell lymphomas.

METHODS

The cells were cultured and incubated with varying concentrations of 2ME2 or MTX. A tetrazolium-based colorimetric assay was used to quantify the anti-proliferative effects of 2ME2 and MTX using a microplate reader. To detect apoptotic and cell cycle distribution changes induced by 2ME2 and MTX, the cells were stained with Annexin V-FITC and/or propidium iodide (PI) and analyzed by flow cytometry.

RESULTS

Lymphoma cell proliferation was inhibited by 50% at concentrations ranging from 0.4 to 1 microM for 2ME2 and 0.06 to 0.2 microM for MTX. Induction of apoptosis by 2ME2 and MTX was observed in the tested cells. 2ME2 was a G2/M-phase specific blocker whereas MTX was an S-phase specific blocker in cell cycle analyses. At 1 microM concentration, 2ME2 and MTX showed similar anti-proliferative effect on the lymphoma cell lines. In previously reported studies, for normal endothelial cells, 1 microM 2ME2 showed no appreciable toxicity, while MTX at this same concentration exhibited significant cytotoxicity. 2ME2 at a therapeutic target concentration of 1 mu M may be an effective and relatively non-toxic drug for the treatment of PCNSL with IOL.

CONCLUSIONS

Our study of the effect of 2ME2 and MTX on anti-proliferation, apoptosis, and cell cycling suggests that 2ME2 is a potential agent for treating PCNSL and IOL.

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.

Angiogenesis in primary central nervous system lymphoma (PCNSL)

Angiogenesis and angiogenic growth factors have a major role in the pathogenesis of malignancies. However, very little is known about the clinical and histopathological relevance of angiogenesis in primary central nervous system lymphoma (PCNSL). We investigated that expression of vascular endothelial growth factor (VEGF) of the lymphoma cells and microvessel density (MVD) were examined in 19 patients with PCNSL. Additionally, the presence of the blood-brain barrier (BBB) was examined using immunohistochemistry and the electron microscopy. MVD was significantly higher in nine cases with VEGF immunoreactivity (VEGF+) than in ten cases with negative immunoreactivity for VEGF (VEGF-) (P < 0.001). VEGF expression was significantly associated with a longer survival (P < 0.005). BBB markers were negative in angiogenic vessels of VEGF+. BBB markers were identified in vessels surrounding tumor cells and tight junctions were also preserved in the capillary endothelium surrounding tumor cells in VEGF-. Angiogenesis is associated with VEGF expression and an absent BBB in the vessels of PCNSL. The BBB may be preserved in lesions with lymphoma cell infiltration, especially in VEGF- PCNSL. VEGF may have a prognostic effect in PCNSL.

[Primary CNS lymphoma in azathioprine therapy for autoimmune diseases: review of the literature and case report]

We present a 31-year-old female patient with primary non-Hodgkin's lymphoma of the CNS after immunosuppressive therapy. Colitis ulcerosa had been diagnosed 2 years previously. Prophylactic therapy with azathioprine over 9 months was stopped after the development of listeria meningitis which was treated successfully with antibiotics. At this time native CCT was normal. Three months later the patient developed an epileptic seizure and multiple cerebral lesions were detected in CCT and MRI. Although antibiotic therapy was started, the cerebral lesions showed no regression. Stereotactic biopsy revealed immunochemical and histologic high-grade malignant B cell lymphoma. The risk of primary CNS lymphoma under azathioprine treatment for an autoimmune disease with a possible congenital immunodeficiency is presented and the literature is reviewed.

Pathology of primary central nervous system lymphoma

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

A 19-year-old male with generalized seizures, unconsciousness and a deviation of gaze

Light chain deposition disease (LCDD) is a form of monoclonal immunoglobulin deposition diseases (MIDD) which in contrast to light-chain derived (AL) amyloidosis is characterized by non-congophilic, non-fibrillary monoclonal protein deposits. Systemic organ deposits are common with the kidney being a major target organ. A clonal lymphoplasmocytic proliferation, e.g. plasmacytoma, is present in the majority of cases. Here we report on a 19-year-old male who presented with generalized seizures and an enhancing white matter lesion on MRI scans. A stereotactic brain biopsy revealed a low-grade B cell lymphoma with plasmacellular differentiation as well as lambda light chain deposits without birefringence under polarized microscopy. No systemic lymphoma manifestations or systemic light chain deposits were found, nor was a monoclonal gammopathy detectable in serum and urine. After systemic chemotherapy with three courses high-dose methotrexate the size of the lesion and the condition of the patient have remained stable for 24 months now. This is the first description of cerebral LCDD developing without systemic disease in conjunction with the diagnosis of a cerebral low-grade B cell lymphoma. We present the clinical, laboratory and radiological findings and discuss the pathogenesis of this unusual LCDD manifestation.

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 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.

The pharmacokinetics of rituximab following an intravitreal injection

Rituximab is a monoclonal antibody directed against the CD20 B-cell antigen and is approved for the treatment of B-cell lymphoma. We investigated the pharmacokinetics of rituximab following intravitreal administration to assess the feasibility of treating primary intraocular lymphoma. Intravitreal injections of rituximab 0.1 ml (1 mg) were performed in rabbits. Drug concentrations in the aqueous and vitreous humor were measured at intervals from 2 to 17 days after administration. The half-life of the total amount of rituximab in the two compartments was calculated to be 4.7 days. The aqueous and vitreous humor drug levels decayed in parallel maintaining an average ratio of approximately seven. Fitting the data to a two-compartment model yielded a clearance from the aqueous humor of 1.2 microl/min. The clearance was less than the reported rate of aqueous humor outflow indicating that elimination by this route could have been sufficient to account for the disappearance of the drug from the eye. The duration of time over which sustained levels of rituximab were achieved suggest that intravitreal administration warrants further investigation as an approach to treating vitreous and anterior chamber infiltrates in patients with primary intraocular lymphoma.

A uniform activated B-cell-like immunophenotype might explain the poor prognosis of primary central nervous system lymphomas: analysis of 83 cases

Most primary central nervous system lymphomas (PCNSLs) in immunocompetent patients are diffuse large B-cell lymphomas (DLBCLs), characterized by poor prognosis, compared with systemic forms. A germinal center B-cell-like (GCB) origin of PCNSL was hypothesized on the basis of BCL-6 expression and ongoing mutational activity. Our goal herein was to determine, for 83 PCNSLs, the percentages of GCB and activated B-cell-like (ABC) phenotypes and their prognostic significance. CD10, BCL-6, MUM1, BCL-2, and CD138 antigens were immunohistochemically labeled on paraffin-embedded sections; the first 4 were positive in 2.4%, 55.5%, 92.6%, and 55.5% of the tumors, respectively. None of the 56 tested samples expressed CD138. Among the 82 patients with complete information, 79 (96.3%) were classified as ABC; 42 (51.2%) expressed BCL-6+ MUM1+, suggesting an "activated GCB" origin; 33 (40.2%) were exclusively MUM1+, and the remaining 4 (4.9%) were negative for all markers tested. These findings provide new insights into interpreting the poor PCNSL prognostic, which may, in part, be due to biologic aggressiveness associated with its activated B-cell-like pattern. We postulate assigning PCNSL a histogenetic "time-slot," overlapping late GC and early post-GC, that could explain the predominant ABC phenotype observed.

Co-existence of intraocular and orbital lymphoma

BACKGROUND

The concomitant occurrence of both intraocular and periocular lymphomas is extremely rare. Periocular involvement by lymphoproliferative disease ranges from benign lymphoid hyperplasia to malignant lymphoma. Intraocular lymphomas usually appear in conjunction with primary central nervous system lymphoma.

CASE REPORTS

We describe clinical characteristics, standardized A- and B-scan ultrasonography, colour Doppler, computerized tomographic and magnetic resonance imaging, and immunohistological findings in three cases of concurrent choroidal and periocular involvement of lymphoma.

DISCUSSION

The clinical presentation of diffuse choroidal tumours may be variable, making diagnosis of intraocular lymphoma troublesome on clinical grounds alone. The high accuracy of colour Doppler imaging is known to be effective in differentiating the benign from the malignant and adds valuable information in the differential diagnosis of a low reflective lesion. We suggest the use of auxiliary examinations such as ultrasonography and colour Doppler imaging to help in the differential diagnosis of choroidal and orbital tumours.

Primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare variant of non-Hodgkin's lymphoma that is increasing in incidence. Methotrexate-based chemotherapy in combination with whole-brain radiotherapy (WBRT) has dramatically improved the outcome of patients. However, treatment-related neurotoxicity is a significant complication, especially after radiotherapy in the elderly. Despite advances in therapy, several important questions remain regarding optimal methotrexate dose, dosing frequency, adjunct chemotherapy, and the impact of deferring WBRT. Advances in biologic therapy and strategies to intensify the delivery of chemotherapy may help to limit the use of radiotherapy, thus lessening potential neurotoxicity. Studies looking at oncogenic proteins as potential prognostic markers for PCNSL may help us to develop risk-adapted therapies.

Ocular presentation of primary central nervous system lymphoma: diagnosis and treatment

Primary ocular lymphoma (POL), a lymphoma of the globe, is a restricted form of primary central nervous system lymphoma (PCNSL) that often progresses to the brain and meninges; frequently it is misdiagnosed until central nervous system (CNS) lymphoma develops. The optimal treatment has not yet been identified. We retrospectively reviewed the course and the treatment of POL in 31 patients. Seventeen patients were treated for isolated POL (group A) and 14 were treated only after CNS disease was diagnosed (group B). The treatment in both groups consisted of systemic chemotherapy, chemotherapy plus radiotherapy (RT) or RT alone. In group A, nine patients (53%) developed CNS progression and five (29%) had ocular recurrence. In group B, seven (50%) had CNS progression and three (21%) ocular relapse. To control for diagnostic lead time, median survival was calculated from initial ocular symptoms and was 60 months in group A and 35 months in group B (P < 0.05). Ocular lymphoma responds to a variety of therapies but treatment with chemotherapy and/or ocular radiotherapy (ORT) failed to prevent CNS progression. Patients whose ocular disease was identified and treated before CNS progression had a significantly improved survival.

Analysis of chromosomal copy number changes and oncoprotein expression in primary central nervous system lymphomas: frequent loss of chromosome arm 6q

Primary central nervous system lymphoma (PCNSL) is a rare disease. A small number of cytogenetic studies of PCNSL have been conducted and several reports have been published on associated molecular and protein expression data. We combined these approaches in a series of eight PCNSL cases, analyzing the chromosomal abnormalities using comparative genomic hybridization (CGH), testing for Epstein Barr virus (EBV) involvement by in situ hybridization for EBER, assessing expression of p53, Bcl-2, Bcl-6 and CD10 by means of immunohistochemistry, and screening for mutations of the TP53 gene by DGGE. TP53 gene mutations and EBV expression were not detected. Most of the cases showed p53, Bcl-6 and Bcl-2 protein expression. CGH revealed DNA copy number changes in all eight cases. The most frequent changes were gains of chromosome 12 (63%), chromosome 18 (50%) and 20q (38%), and loss of chromosome arm 6q (75%). No correlation between protein expression and chromosomal abnormalities was found in these eight cases. Although gains of chromosome 12, 18 and 20q and loss of 6q have also been reported in systemic diffuse large B-cell lymphomas, the frequency of 6q deletion is clearly higher in PCNSL. This creates a similarity to primary lymphomas of the testes that also frequently have deletions of 6q. This suggests that suppressor genes located on chromosome 6q may play a role in the development of lymphomas at immunoprivileged sites, like the CNS.

Local cryoglobulin deposition in primary central nervous system lymphoma

Primary central nervous system lymphomas (PCNSLs) represent malignant non-Hodgkin's B-cell lymphomas confined to the central nervous system. Recent years have brought a dramatic increase in the frequency of PCNSL in the immunocompromised and immunocompetent populations. Cryoglobulins are cold-precipitable immunoglobulins associated with a number of infectious, autoimmune, and neoplastic disorders. Although it is known that patients with hematologic malignancies (eg, B-cell lymphomas, chronic lymphocytic leukemia, plasma cell dyscrasias) may have cryoglobulinemias and cryoglobulin deposition in several organs (eg, kidney, liver skin, blood vessels, peripheral nervous system), PCNSL associated with cryoglobulin deposition has not been previously described. This report demonstrates localized cryoglobulin deposition within the tumor bed in an immunocompetent patient with PCNSL.

Primary ocular lymphoma: clinical features, diagnosis, and treatment

Primary ocular lymphoma involves the globe in the absence of any systemic or central nervous system lymphoma. Diagnosis is frequently delayed and often made only after the tumor has progressed to the brain and meninges. Clinical features, cues in ancillary tests, and immunologic and molecular advances that support the diagnosis are reviewed. The current treatment options are discussed. Although advances have been made, the optimal treatment for primary ocular lymphoma remains to be identified

Intrathecal chemotherapy for recurrent central nervous system intraocular lymphoma

PURPOSE

To report the use of intrathecal chemotherapy for two patients with recurrent central nervous system (CNS) intraocular lymphoma.

DESIGN

Two interventional case reports.

PARTICIPANTS

The clinical course of two patients with documented recurrent CNS intraocular lymphoma were retrospectively reviewed.

INTERVENTION

Both patients had previously undergone external beam radiation therapy to the orbit and brain, as well as systemic methotrexate (MTX) and intrathecal cytarabine (Ara-C), for primary CNS intraocular lymphoma. Both patients developed recurrent CNS intraocular lymphoma and treatment involved intrathecal MTX and Ara-C delivered by means of an Ommaya reservoir.

MAIN OUTCOME MEASURE

Survival and resolution of intraocular lymphoma.

RESULTS

Complete remission of the CNS intraocular lymphoma was seen in both patients. Both patients maintain reading visual acuity in at least one eye. Both patients remain disease free with lymphoma in remission for greater than 5 years after initial diagnosis.

CONCLUSIONS

Intrathecal chemotherapy for recurrent CNS intraocular lymphoma seems to be effective in preserving vision and possibly increasing survival.

Expression of B-cell-attracting chemokine 1 (CXCL13) by malignant lymphocytes and vascular endothelium in primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare but often rapidly fatal form of non-Hodgkin B-cell lymphoma that arises within the central nervous system (CNS) and has a low propensity to metastasize. We performed immunohistochemistry on formalin-fixed, paraffin-embedded brain biopsy specimens from 24 patients with PCNSL to investigate the expression of B cell-attracting chemokine 1 (BCA-1, CXCL13), a lymphoid chemokine involved in B-cell compartmental homing within secondary lymphoid organs and recently implicated in the pathogenesis of inflammatory and malignant lymphocyte-mediated diseases. Whereas BCA-1 was not detected in normal human brain, all 24 brain biopsy specimens containing PCNSL were positive for BCA-1. Double immunostaining on selected specimens localized BCA-1 to malignant B lymphocytes and vascular endothelium. In contrast, 2 chemokines implicated particularly in T-cell movement, secondary lymphoid tissue chemokine (SLC, CCL21) and Epstein-Barr virus-induced molecule 1 ligand chemokine (ELC, CCL19), were expressed only by occasional stromal cells in 2 and 4 of the 24 specimens, respectively. Tumor cells stained positively for CXCR5, the primary receptor for BCA-1. In situ hybridization verified the expression of BCA-1 mRNA by malignant B cells, but not vascular endothelium, within the tumor mass, suggesting that vascular endothelial BCA-1 expression may be consequent to transcytosis. In PCNSL, expression of BCA-1 by malignant lymphocytes and vascular endothelium may influence tumor development and localization to CNS.

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.

Analysis of immunoglobulin H gene rearrangement by polymerase chain reaction in primary central nervous system lymphoma

OBJECT

Diagnosing primary central nervous system lymphoma (PCNSL) may be difficult either because of a paucity of tumor cells in the brain biopsy specimens or a failure to demonstrate monoclonality on immunomorphological studies. Monoclonality can also be demonstrated by amplification of the rearranged immunoglobulin H genes by polymerase chain reaction (PCR) to the framework region (FR)3 and FR2 complementarity determining region (CDR)-III and CDR-II of these genes. The PCR method is feasible with formalin-fixed, paraffin-embedded biopsy material and has proven to be helpful in the diagnosis of non-Hodgkin lymphoma on biopsy samples obtained from various locations in the body. Nevertheless, few studies have addressed the value of this method in the context of PCNSL. In the present study, the contribution of both FR3 single and FR2 seminested PCR procedures for confirming the diagnosis of PCNSL was estimated retrospectively in 30 cases of PCNSL and in three cases of epidural lymphoma.

METHODS

Twenty-eight cases of immunophenotypically confirmed PCNSL and two of suspected lymphoma were studied. Tissue specimens obtained in 22 cases of other cerebral diseases, among which were various inflammatory conditions. were used as negative controls. In 18 (60%) of 30 cases the results of FR3 PCR demonstrated monoclonality, whereas FR2 PCR showed monoclonality in 12 cases (40%). In 11 cases FR3 PCR yielded monoclonal patterns and FR2 PCR did not, whereas reversibly in five cases FR2 PCR proved monoclonality and FR3 PCR failed to do so. Adding the results of FR3 to those of FR2 PCR, monoclonal patterns were obtained in 23 (77%) of 30 cases. In both cases in which lymphoma was suspected but not proven immunomorphologically, FR3 PCR revealed monoclonality, as did FR2 PCR in one case. In all 22 control lesions either polyclonal patterns were seen or no consistent patterns were obtained. In the PCNSL group, older age of patients and multifocal presentation of lesions on neuroimaging were significantly associated with worse survival. No correlation between histological subtype and clinical outcome was elucidated.

CONCLUSIONS

The application of FR3 and FR2 PCR is a useful additional tool in making the diagnosis of PCNSL. Moreover, in some cases the PCR method may be essential in distinguishing neoplasia from reactive conditions.

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.

Primary central nervous system lymphomas: incidence and survival in the Southern and Eastern Netherlands

BACKGROUND

An excessive increase in the incidence of primary central nervous system lymphoma (PCNSL) has been reported since the mid-1980s in the U.S. and U.K. Clinical studies have shown that radiotherapy and chemotherapy may prolong survival. In the current study, the authors describe the incidence, treatment, and survival of an unselected group of patients with PCNSL in the southern and eastern Netherlands.

METHODS

Data regarding patients diagnosed between 1989-1994 were obtained from 4 population-based regional cancer registries in the southern and eastern Netherlands (n = 86) and the Eindhoven Cancer Registry for 1980-1988 (n = 6). Lymphomas were registered as PCNSL when a tissue diagnosis of CNS lymphoma was established for a patient with neurologic symptoms (i.e., lymphomas were not necessarily restricted to the CNS at the time of diagnosis). Only patients diagnosed during their lifetime with Stage I disease, Stage "IV" disease (i.e., diffuse CNS lymphoma), or disease of unknown stage were included (63 patients, 8 patients, and 15 patients, respectively, between 1989-1994). For 80 patients (93%) follow-up was complete until January 1, 1997.

RESULTS

Between 1989-1994, an average World Standardized Rate of 2.3 cases and 1.7 cases per 1 million person-years, respectively, was reported for males and females. The median age of the patients at the time of diagnosis was 62 years, and was 66 years for patients with an unknown disease stage. In the area of the Eindhoven Cancer Registry the occurrence of PCNSL more than doubled from < 2% of all histologically confirmed primary CNS malignancies diagnosed between 1980-1985 to approximately 4% of cases diagnosed between 1986-1994. The median survival of all the patients was 4.1 months; the median survival was 5.8 months for patients with limited (Stage I and Stage IV) disease and was 0.6 months for patients with an unknown stage of disease. Approximately 65% of the patients with limited disease received radiotherapy and approximately 35% of such patients received chemotherapy. Furthermore, chemotherapy was given more often to patients age < 60 years who tended to have a slightly better survival than patients age > or = 60 years.

CONCLUSIONS

The increase in the incidence of PCNSL in the 1980s may be explained in large part by changes in diagnostics and registration. The relatively high incidence and low survival rate of PCNSL in the southern and eastern Netherlands reported in the 1990s may be due in part to the inclusion of patients with systemic lymphoma and immunodeficiency disorders. However, a significant improvement in the prognosis of patients with PCNSL in the southern and eastern Netherlands diagnosed in the 1990s is unlikely.

Survival of AIDS patients with primary central nervous system lymphoma is dramatically improved by HAART-induced immune recovery

OBJECTIVE

To evaluate the impact of immune recovery induced by highly active antiretroviral therapy (HAART) on the survival of AIDS patients with primary central nervous system lymphoma (PCNSL).

METHODS

In a multicentric retrospective analysis, 29 HIV-infected patients with histologically confirmed PCNSL were identified. To evaluate median survival, Kaplan-Meier statistics were used. To explore the effects of different variables on survival, a Weibull accelerated failure time regression analysis was performed.

RESULTS

Median age at manifestation of PCNSL was 39.1 years and median CD4 cell count was 11 x 10(6) cells/l. Seventy per cent of the patients had had a prior AIDS-defining illness. Cranial radiation (CR) was given to 12 out of 29 patients. Six patients were treated with HAART. Survival time of these patients and of the patients treated with CR alone differed significantly from those receiving neither CR nor HAART (median Kaplan-Meier survival estimate: 1093, 132, and 33 days, respectively). In the multivariate regression model, HAART and CR were identified as the only variables independently associated with prolonged survival. HAART versus no HAART and CR versus no CR increased the time to event by a factor of 6.1 (95% confidence interval, 2.4-16.0; P = 0.0002) and 3.1 (95% confidence interval, 1.5-6.3; P = 0.002), respectively. Four out of six patients on HAART showed a marked immune recovery and survived for more than 1.5 years, with two patients still alive.

CONCLUSION

Data from this cohort indicate that immune recovery induced by HAART leads to dramatic improvement in survival of patients with AIDS-associated PCNSL. These findings may have important implications for future treatment strategies.

Distinct primary central nervous system lymphoma defined by comparative genomic hybridization and laser scanning cytometry

We investigated chromosomal alterations using comparative genomic hybridization (CGH), and DNA ploidy patterns using laser scanning cytometry (LSC) in 8 primary central nervous system lymphomas (PCNSLs). The average number of chromosomal alterations detected by CGH was 6.9 (gain: 4.1, deletion: 2.8). Frequent alterations were gains of chromosomes 12, 18q, and X, and deletion of 6q, which were similar to those seen in non-CNS diffuse large B-cell lymphoma. DNA aneuploidy was detected by LSC in 4 of the 8 cases. The DNA aneuploid lymphomas had more chromosomal alterations than the DNA diploid ones (9.3 vs. 4.5, P <.05). The former had higher MIB-1 indices than the latter. The present investigation indicates that although most of the PCNSL are histologically uniform, they are divided cytogenetically into DNA aneuploid and diploid tumors.

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.

Primary CNS lymphoma: clinical presentation, pathological classification, molecular pathogenesis and treatment

Primary CNS lymphomas (PCNSL) represent malignant non-Hodgkin's B cell lymphomas, which are confined to the central nervous system. They show a dramatic increase in frequency in the immunocompromised as well as in the immunocompetent population. Recent studies have identified germinal center B cells as the cellular origin of PCNSL; however, the details of their molecular pathogenesis still remain to be elucidated. Treatment recommendations are not clearly established. Radiotherapy (RT) is efficient in terms of tumor response, but not curative. Median survival after RT alone is about 1 year. According to the results of uncontrolled studies the combination of RT and chemotherapy based on high-dose methotrexate (HD-MTX) is most efficient in terms of survival rates. However, long-term neurotoxicity overshadows treatment efficacy, especially in patients over 60 years of age. The authors favor the systematic evaluation of chemotherapy alone with protocols including HD MTX, because unicenter results are promising in terms of both survival as well as quality of life in long term survivors.