Clinical relevance of flow cytometric immunophenotyping of the cerebrospinal fluid in patients with diffuse large B-cell lymphoma

Comparison of standardized prophylactic high-dose and intrathecal methotrexate for DLBCL with a high risk of CNS relapse

The efficacy of high-dose methotrexate (HD-MTX) for central nervous system (CNS) relapse prophylaxis in patients with high-risk diffuse large B-cell lymphoma (DLBCL) is controversial. We compared the prophylactic effects of HD-MTX and intrathecal methotrexate (IT-MTX) on CNS relapse in high-risk DLBCL, in a multicenter retrospective study. A total of 132 patients with DLBCL at high risk of CNS relapse who received frontline chemotherapy and IT-MTX from 2003 to 2013 (n = 34) or HD-MTX from 2014 to 2020 (n = 98) were included. After a median follow-up of 52 months (range: 9-174), 11 patients had isolated CNS relapse: six (6.1%) in the HD-MTX group and five (14.7%) in the IT-MTX group. The median time until CNS relapse was 38 months (range: 11-122), and the cumulative incidence of CNS relapse at 3 years was 3.9% in the HD-MTX group and 6.1% in the IT-MTX group (P = 0.93). Similar results were obtained after adjusting for background factors using propensity score-matched analysis (4.5% HD-MTX vs. 7.6% IT-MTX, P = 0.84). The CNS relapse rate in HD-MTX-treated patients was equivalent to that in IT-MTX patients, demonstrating that HD-MTX was not superior to IT-MTX in preventing CNS relapse.

Initial and follow-up evaluations on cerebrospinal fluid involvement by hematologic malignancy

Central nervous system (CNS) involvement is a serious complication in hematologic malignancy, and early detection and management of CNS involvement in these cases significantly impact the prognosis. Currently, there is no consensus on the use of multiparametric flow cytometry (MFC) and conventional cytology (CC) testing for initial and follow-up cerebrospinal fluid (CSF) specimens to diagnose CNS involvement by hematologic malignancy. In our institution, after initial MFC and CC, two subsequent negative MFCs are required before discontinuing MFC. The aim of this study is to evaluate the outcome of this approach. CSF cytology and MFC reports were retrieved from Laboratory Information System, and data was reviewed. Between January 2020 and December 2021, 1789 CSF samples from 280 patients were submitted for CSF analysis. For those 517 CSF samples tested by both MFC and CC, 97 cases tested positive by both MFC and CC with 95% concordance. Eighteen cases were MFC + /CC - and 7 were MFC - /CC + . Thirty-six cases had initially positive MFCs followed by more than one MFC evaluation. Among those 36 cases, 22 cases (61.1%) converted to negative after the second follow-up sample, 9 cases (25%) were continuously positive for at least three samples, and 5 cases (13.9%) exhibited negative to positive conversion. Compared to negative CSF cases, positive CSFs had higher total nucleated cell count and higher total protein levels while red blood cells, glucose, and lactate dehydrogenase levels remained at comparable levels. The concordance between MFC and CC was excellent. The high incidence of positive MFCs on two or more follow-up samples and the high frequency of negative MFC to positive conversion indicate the necessity of repeated negative MFCs before discontinuing MFC. The fact that more than half of the positive cases converted to negative after the second CSF specimen and most follow-up positive cases can be detected by CC alone suggests it is adequate to use CC alone for follow-up CSF study after two consecutive negative MFCs.

Central nervous system prophylaxis in diffuse large B-cell lymphoma: What does the evidence tell us?

Secondary involvement of the central nervous system (CNS) by diffuse large b-cell lymphoma (DLBCL) is a rare yet often catastrophic event for DLBCL patients. As standard first-line therapy for DLBCL with rituximab, cyclophosphamide, doxorubicin, vincristine, and prednisone (R-CHOP) does not cross the blood-brain barrier, one approach to lessen the risk of CNS relapse has been to include additional agents, primarily methotrexate, directed at the CNS with standard R-CHOP although the timing, dose, and mode of administration differs widely across treating physicians. This practice derives from decades of non-randomized, often retrospective data with inconsistent outcomes. The current available tools and risk models are imprecise in their ability to predict which patients are truly at risk of secondary CNS relapse and more recent, large-scale real-world analyses call into question these longstanding practices. In a field lacking any prospective, randomized studies, this review synthesizes the available data investigating the utility of CNS prophylaxis in patients with DLBCL receiving 1st line therapy.

Detection of clonotypic DNA in the cerebrospinal fluid as a marker of central nervous system invasion in lymphoma

The NGS-MRD assay detected clonotypic DNA in 100% of CSF samples from patients who had lymphoma with parenchymal CNS involvement.

Clonotypic DNA in CSF was present in 36% of newly diagnosed aggressive lymphomas and was associated with a 29% risk of CNS recurrence.

The diagnosis of parenchymal central nervous system (CNS) invasion and prediction of risk for future CNS recurrence are major challenges in the management of aggressive lymphomas, and accurate biomarkers are needed to supplement clinical risk predictors. For this purpose, we studied the results of a next-generation sequencing (NGS)–based assay that detects tumor-derived DNA for clonotypic immunoglobulin gene rearrangements in the cerebrospinal fluid (CSF) of patients with lymphomas. Used as a diagnostic tool, the NGS-minimal residual disease (NGS-MRD) assay detected clonotypic DNA in 100% of CSF samples from 13 patients with known CNS involvement. They included 7 patients with parenchymal brain disease only, whose CSF tested negative by standard cytology and flow cytometry, and 6 historical DNA aliquots collected from patients at a median of 39 months before accession, which had failed to show clonal rearrangements using standard polymerase chain reaction. For risk prognostication, we prospectively collected CSF from 22 patients with newly diagnosed B-cell lymphomas at high clinical risk of CNS recurrence, of whom 8 (36%) had detectable clonotypic DNA in the CSF. Despite intrathecal prophylaxis, a positive assay of CSF was associated with a 29% cumulative risk of CNS recurrence within 12 months of diagnosis, in contrast with a 0% risk among patients with negative CSF (P = .045). These observations suggest that detection of clonotypic DNA can aid in the diagnosis of suspected parenchymal brain recurrence in aggressive lymphoma. Furthermore, the NGS-MRD assay may enhance clinical risk assessment for CNS recurrence among patients with newly diagnosed lymphomas and help select those who may benefit most from novel approaches to CNS-directed prophylaxis.

Lymphocyte Immunophenotyping and CD4/CD8 Ratio in Cerebrospinal Fluid for the Diagnosis of Sarcoidosis-related Uveitis

Background: This study aimed to assess the diagnostic relevance of CD4/CD8 ratio in cerebrospinal fluid (CSF) for the etiological diagnosis work-up of uveitis.Methods: We consecutively included patients who were referred to our department for the diagnostic workup of intermediate and/or posterior uveitis. Etiological diagnoses were established in a blind manner regarding CD4/CD8 ratio.Results: Fifty-two patients were included. A diagnosis of ocular sarcoidosis was made in 15 (29%) patients, 21% had another determined diagnosis while 50% remained of undetermined origin. Median CD4/CD8 ratio in CSF was 4.57 (IQR 3.39-5.47) in ocular sarcoidosis, 1.74 (1.60-3.18) in uveitis due to other determined cause (P = .008), and 2.83 (2.34-3.54) in those with uveitis of undetermined origin (P = .007). CD4/CD8 ratio >3.23 was associated with a diagnosis of ocular sarcoidosis.Conclusion: Determination of CD4/CD8 ratio in CSF can be useful for diagnosis work-up since a CD4/CD8 ratio >3.23 in CSF is associated with ocular sarcoidosis.

Primary Intra-Axial Diffuse Large B-Cell Lymphoma in Immunocompetent Patients: Clinical Impact of Molecular Analysis and Histogenetic Evaluation

Primary central nervous system (CNS) diffuse large B-cell lymphoma (DLBCL) represents less than 1% of non-Hodgkin lymphomas and 2%-3% of brain tumors. Primary CNS DLBCL occurs sporadically in healthy patients. Tumor development and progression have been associated with reduced/absent expression of human leukocyte antigen class I and II proteins; increased expression of CXCR4, CXCL12, CXCR5, and CCR7; mutations of VH4/34, BCL6, MYC, and PAX5 genes; and rearrangement of immunoglobulin heavy and light chain genes. Generally, DLBCL is a single supratentorial lesion (60%-70%), and stereotactic biopsy and intraoperative examination are the main diagnostic methods. Distinctive histologic features are a diffuse growth pattern and angioinvasiveness. Most neoplastic cells resemble centroblasts and exhibit positive CD20, CD22, PAX5, CD79a, and MUM1 expression. The prognosis of primary CNS DLBCL is less favorable than that of nodal DLBCL, and DLBCL subtype, strong FOXP1 immunoreactivity, MYC and BCL2 overexpression, and BCL6 translocations are associated with poor prognosis.

Advances in risk assessment and prophylaxis for central nervous system relapse in diffuse large B-cell lymphoma

Central nervous sytem recurrence of diffuse large B-cell lymphoma is an uncommon but devastating event, making identification of patients at high risk for relapse within the central nervous system essential for clinicians. Modern risk stratification includes both clinical and biological features. A validated clinical risk model employing the five traditional International Prognostic Index risk factors plus renal or adrenal involvement can identify a high-risk patient population with a central nervous system recurrence risk of greater than 10%. Lymphoma involvement of certain discrete extranodal sites such as the testis also confers increased risk, even in stage I disease. Adverse biological risk factors for central nervous system relapse include presence of translocations of MYC, BCL2 and/or BCL6, in so-called double- or triple-hit lymphoma. Immunohistochemically detectable co-expression of MYC and BCL2 in the absence of translocations also portends an increased risk of relapse within the central nervous system, particularly in the setting of the activated B-cell-like subtype of diffuse large B-cell lymphoma. The role, method, and timing of prophylactic therapy remain controversial based on the available data. We review both intrathecal and systemic strategies for prophylaxis in high-risk patients. Our preference is for systemic methotrexate in concert with standard chemoimmunotherapy in the majority of cases. Several novel agents have also demonstrated clinical activity in primary and secondary central nervous system lymphoma and warrant future investigation in the prophylactic setting.

Cerebrospinal fluid biomarkers of malignancies located in the central nervous system

CNS malignancies include primary tumors that originate within the CNS as well as secondary tumors that develop as a result of metastatic cancer. The delicate nature of the nervous systems makes tumors located in the CNS notoriously difficult to reach, which poses several problems during diagnosis and treatment. CSF can be acquired relatively easy through lumbar puncture and offers an important compartment for analysis of cells and molecules that carry information about the malignant process. Such techniques have opened up a new field of research focused on the identification of specific biomarkers for several types of CNS malignancies, which may help in diagnosis and monitoring of tumor progression or treatment response. Biomarkers are sought in DNA, (micro)RNA, proteins, exosomes and circulating tumor cells in the CSF. Techniques are rapidly progressing to assess these markers with increasing sensitivity and specificity, and correlations with clinical parameters are being investigated. It is expected that these efforts will, in the near future, yield clinically relevant markers that aid in diagnosis, monitoring and (tailored) treatment of patients bearing CNS tumors. This chapter provides a summary of the current state of affairs of the field of biomarkers of different types of CNS tumors.

Central Nervous System Prophylaxis for Aggressive B-cell Lymphoma: Who, What, and When?

Central nervous system (CNS) relapse of aggressive B-cell lymphoma is a rare but serious complication with poor survival. Different approaches have been used to define risks factors for CNS relapse and establish prophylactic measures. Although patients with low or intermediate risk of CNS relapse should not undergo special diagnostic or therapeutic measures, CNS MRI as well as cytology and flow cytometry of the cerebrospinal fluid are suggested for high-risk patients (and patients with testicular involvement) at diagnosis, and prophylactic high-dose methotrexate in patients without proven CNS involvement. Future risk and treatment models may include molecular features and new treatment options.

Overexpression of syndecan-1, MUC-1, and putative stem cell markers in breast cancer leptomeningeal metastasis: a cerebrospinal fluid flow cytometry study

Background

Cancer is a mosaic of tumor cell subpopulations, where only a minority is responsible for disease recurrence and cancer invasiveness. We focused on one of the most aggressive circulating tumor cells (CTCs) which, from the primitive tumor, spreads to the central nervous system (CNS), evaluating the expression of prognostic and putative cancer stem cell markers in breast cancer (BC) leptomeningeal metastasis (LM).

Methods

Flow cytometry immunophenotypic analysis of cerebrospinal fluid (CSF) samples (4.5 ml) was performed in 13 consecutive cases of BCLM. Syndecan-1 (CD138), MUC-1 (CD227) CD45, CD34, and the putative cancer stem cell markers CD15, CD24, CD44, and CD133 surface expression were evaluated on CSF floating tumor cells. The tumor-associated leukocyte population was also characterized.

Results

Despite a low absolute cell number (8 cell/μl, range 1–86), the flow cytometry characterization was successfully conducted in all the samples. Syndecan-1 and MUC-1 overexpression was documented on BC cells in all the samples analyzed; CD44, CD24, CD15, and CD133 in 77%, 75%, 70%, and 45% of cases, respectively. A strong syndecan-1 and MUC-1 expression was also documented by immunohistochemistry on primary breast cancer tissues, performed in four patients. The CSF tumor population was flanked by T lymphocytes, with a different immunophenotype between the CSF and peripheral blood samples (P ≤ 0.02).

Conclusions

Flow cytometry can be successfully employed for solid tumor LM characterization even in CSF samples with low cell count. This in vivo study documents that CSF floating BC cells overexpress prognostic and putative cancer stem cell biomarkers related to tumor invasiveness, potentially representing a molecular target for circulating tumor cell detection and LM treatment monitoring, as well as a primary target for innovative treatment strategies. The T lymphocyte infiltration, documented in all CSF samples, suggests a possible involvement of the CNS lymphatic system in both lymphoid and cancer cell migration into and out of the meninges, supporting the extension of a new form of cellular immunotherapy to LM. Due to the small number of cases, validation on large cohorts of patients are warranted to confirm these findings and to evaluate the impact and value of these results for diagnosis and management of LM.

Electronic supplementary material

The online version of this article (doi:10.1186/s13058-017-0827-4) contains supplementary material, which is available to authorized users.

Immunophenotyping of the cerebrospinal fluid as a prognostic factor at diagnosis of acute lymphoblastic leukemia in children and adolescents

This study aimed at evaluating the use of immunophenotyping (IMP) in the identification of blast cells in the cerebrospinal fluid (CSF) of children and adolescents with acute lymphoblastic leukemia (ALL). Sixty-seven patients aged 18 years or younger were included. Fifty-five CSF samples were analyzed at initial diagnosis and 17 at the time of relapse. A cytological analysis (CA) was performed in all 72 samples, while IMP was done in 63. Blasts were identified in only three samples by CA, whereas all three samples were found negative by IMP, one of which had no isolation of nucleated cells after centrifugation. Among the samples analyzed by IMP, 11 showed a positive blast count, two of which had been inconclusive using CA. No equivalence was found between CA and IMP results (p = 0.55). CSF IMP positivity was not associated with other risk factors for ALL relapse. Among the 55 patients included at the time of diagnosis of ALL, eight relapsed during follow-up. Considering the cases of central nervous system (CNS) relapse, one of the patients belonged to the CSF IMP-positive group (11%) at diagnosis, and the other two cases, to the IMP-negative (5%) group. Detection of CSF blast cells using IMP was associated with a worse overall (p < 0.0001) and event-free survival (p < 0.0001). These results show that CSF IMP may be a useful additional method to conventional CA in the diagnosis of CNS involvement in ALL, and for the identification of high-risk subgroups that would benefit from an intensified therapy.

Usefulness of Flow Cytometric Analysis for Detecting Leptomeningeal Diseases in Non-Hodgkin Lymphoma

BACKGROUND

The clinical usefulness of flow cytometry (FCM) for the diagnosis of leptomeningeal diseases (LMD) in non-Hodgkin lymphomas has been suggested in previous studies but needs to be further validated. With this regards, we evaluated the use of FCM for LMD in a series of Korean patients with non-Hodgkin lymphoma.

METHODS

FCM and cytomorphology were conducted using samples obtained from clinically suspected LMD patients, follow-up LMD patients, and those with high risk of developing tumorigenic diseases. We then compared results of FCM and cytomorphology. In total, 55 and 47 CSF samples were analyzed by FCM and cytomorphology, respectively.

RESULTS

Of the samples analyzed, 25.5% (14/55) and 12.8% (6/47) were positive by FCM and cytomorphology, respectively. No samples were determined as negative by FCM but positive by cytomorphology. Seven patients were positive only by FCM and negative by cytomorphology, and six among them were clinically confirmed to have LMD either by follow-up cytomorphology or imaging study.

CONCLUSIONS

We observed a high detection rate of tumor cells by FCM compared with cytomorphology. FCM study can be useful in early sensitive detection of LMD.

Cerebrospinal fluid from patients with hematopoietic neoplasms: the need for an integrated approach

INTRODUCTION

Cerebrospinal fluid (CSF) evaluation plays an increasing role in the diagnosis and staging of hematopoietic neoplasms. The evaluation is based on the cytomorphologic evaluation (CE) of the specimen and flow cytometry study (FCS). The impact of the increased sensitivity of multicolor FCS and its correlation with the morphological analysis of CSF needs to be evaluated to better guide clinical management.

MATERIALS AND METHODS

CSF specimens sent for CE and FCS obtained over a 9-month period were retrospectively analyzed. Cases were considered completely discordant if one method detected an abnormal hematologic population and the corresponding method was negative and partially discordant if FCS detected an abnormal hematologic population and the CE was atypical or suspicious. Root cause analysis of these discrepancies was performed.

RESULTS

A total of 78 of 361 cases (22%) had discordant results; 72 cases were from patients with hematopoietic neoplasms-22 cases were completely discordant and 50 were partially discordant. FCS had a sensitivity of 95.3% and a specificity of 98.1% for detecting abnormal hematopoietic populations. CE rendered a positive diagnosis in 17.6% of cases with a specificity of 100%.

CONCLUSIONS

Our series demonstrates evaluation of CSF involvement by hematopoietic malignancy with FCS is more sensitive than and equally specific as CE. Nonetheless, CE remains one of the mainstays in the evaluation of CSF specimens. Optimizing cytologic evaluation through process modifications including decreasing screening area and evaluation of multiple preparations increased the detection rate of malignant cells. As such, optimal CSF evaluation and integration FCS is critical in patient management.

How to facilitate early diagnosis of CNS involvement in malignant lymphoma

INTRODUCTION

Making the diagnosis of secondary CNS involvement in lymphoma can be difficult due to unspecific signs and symptoms, limited accessibility of brain/myelon parenchyma and low sensitivity and/or specifity of imaging and cerebrospinal fluid (CSF) examination currently available. Areas covered: MRI of the total neuroaxis followed by CSF cytomorphology and flow cytometry are methods of choice when CNS lymphoma (CNSL) is suspected. To reduce the numerous pitfalls of these examinations several aspects should be considered. New CSF biomarkers might be of potential diagnostic value. Attempts to standardize response criteria are presented. Expert commentary: Diagnosing CNSL remains challenging. Until diagnostic methods combining high sensitivity with high specifity are routinely introduced, high level of awareness and optimal utilization of examinations currently available are needed to early diagnose this potentially devastating disease.

Brain stereotactic biopsy flow cytometry for central nervous system lymphoma characterization: advantages and pitfalls

BACKGROUND

Brain stereotactic biopsy (SB) followed by conventional histopathology and immunohistochemistry (IHC) is the gold standard approach for primary central nervous system lymphoma (PCNSL) diagnosis. Flow cytometry (FCM) characterization of fine-needle aspiration cytology and core needle biopsies are increasingly utilized to diagnose lymphomas however, no biological data have been published on FCM characterization of fresh single cell suspension from PCNSL SB. The aim of this study was to establish the feasibility and utility of FCM for the diagnosis and characterization of brain lymphomas from a tissue samples obtained by a single SB disaggregation.

METHODS

Twenty-nine patients with a magnetic resonance suggestive for PCNSL entered the study. A median of 6 SB were performed for each patient. A cell suspension generated from manual tissue disaggregation of a single, unfixed, brain SB, was characterized by FCM. The FCM versus standard approach was prospectively compared.

RESULTS

FCM and IHC showed an high degree of agreement (89 %) in brain lymphoma identification. By FCM, 16 out of 18 PCNSL were identified within 2 h from biopsy. All were of B cell type, with a heterogeneous CD20 mean fluorescence intensity (MFI), CD10 positive in 3 cases (19 %) with surface Ig light chain restriction documented in 11 cases (69 %). No false positive lymphomas cases were observed. Up to 38 % of the brain leukocyte population consisted of CD8 reactive T cells, in contrast with the CD4 positive lymphocytes of the peripheral blood samples (P < 0.001). By histopathology, 18 B-PCNSL, only one CD10 positive (5 %), 1 primitive neuroectodermal tumor (PNET) and 10 gliomas were diagnosed. A median of 6 days was required for IHC diagnosis.

CONCLUSION

Complementary to histopathology FCM can contribute to a better characterization of PCNSL, although necrosis and previous steroid treatment can represent a pitfall of this approach. A single brain SB is a valid source for accurate FCM characterization of both lymphoma and reactive lymphocyte population, routinely applicable for antigen intensity quantification and consistently documenting an active mechanism of reactive CD8 T-lymphocytes migration in brain lymphomas. Moreover, FCM confirmed to be more sensitive than IHC for the identification of selected markers.

Accuracy of flow cytometry and cytomorphology for the diagnosis of meningeal involvement in lymphoid neoplasms: A systematic review

Central nervous system (CNS) involvement by lymphoid neoplasms is a relatively infrequent event that demands accurate identification. The purpose of this article is to review studies comparing diagnostic accuracy of flow cytometry (FCM) and cytomorphology (CM) for meningeal involvement from lymphoid neoplasms. Primary publications from the last 26 years were identified searching MedLine, Scopus, and Web of Science and systematically scanning bibliographies of identified articles. Only studies reporting complete results were included. We assessed study quality using the QUADAS-2 tool. For each study, we extracted informations regarding study population, technical details about sample preparation, data analysis, and results. Twenty-seven studies were included. A great heterogeneity regarding study populations and analytical procedures was observed among studies. Percentages of samples giving a positive result with both FCM and CM range from 0.3% to 42.9% among studies, whereas double negative samples go from 0% to 96.3%. Samples with positive FCM but negative CM are reported by 89% (24/27) of the studies with rates ranging from 3.5% to 61.5% of total specimens. On the contrary, samples with positive CM and negative FCM are found in 48% (13/27) of the studies with percentages ranging from 0.5% to 10%. Despite all the differences observed among studies, almost all of them state that employing flow cytometry along with conventional cytology increases the number of positive CSF samples for lymphoma involvement, although a few cases remain in whom only morphology can correctly identify malignant cells. Diagn. Cytopathol. 2016;44:841-856. © 2016 Wiley Periodicals, Inc.

Unilateral uveitis masquerade syndrome caused by diffuse large B-cell lymphoma diagnosed using multiparametric flow cytometry of the aqueous humor

BACKGROUND

The uveitis masquerade syndromes (UMS) are a group of ocular diseases that may mimic chronic intraocular inflammation. Many malignant entities such as non-Hodgkin's lymphomas may masquerade as uveitis. We report a case of an HIV-positive patient with masquerade syndrome presenting unilateral uveitis.

CASE REPORT

45-year-old Caucasian man with a diagnosis of diffuse large B-cell lymphoma (DLBCL). The patient was diagnosed by a biopsy of an abdominal mass which showed fragments of gastric mucosa with diffuse growth of neoplastic cells. At diagnosis, the patient suffered from unilateral blurring of vision and a sudden decrease of left-eye visual acuity. A slit-lamp examination of the left eye revealed a diagnosis of anterior uveitis. The patient exhibited no signs of posterior uveitis. An anterior-chamber paracentesis was performed and analyzed by multiparameter flow cytometry (MFC), showing cells CD45, CD19, CD20, CD22, and CD38 positives, and moderate expression of CD10 with kappa light chain restriction, showing a monoclonal B-cell population. The patient received CHOP-R with intrathecal methotrexate followed by consolidation high dose methotrexate obtaining a complete response which is ongoing.

CONCLUSION

Differential diagnosis between chronic uveitis and ocular lymphoma may be challenging. We advocate anterior-chamber paracentesis in cases of refractory uveitis in patients with hematologic malignancies. © 2016 International Clinical Cytometry Society.

Diagnostic and prognostic significance of flow cytometry immunophenotyping in patients with leptomeningeal carcinomatosis

Some patients with epithelial-cell cancers develop leptomeningeal carcinomatosis (LC), a severe complication difficult to diagnose and with an adverse prognosis. This study explores the contribution of flow cytometry immunophenotyping (FCI) to the diagnosis and prognosis of LC. Cerebrospinal fluid (CSF) samples from patients diagnosed with LC were studied using FCI. Expression of the epithelial-cell adhesion molecule (EpCAM) was the criterion used to identify the epithelial cells. To test the diagnostic precision, 144 patients (94 diagnosed with LC) were included. The prognostic value of FCI was evaluated in 72 patients diagnosed with LC and eligible for therapy. Compared with cytology, FCI showed greater sensitivity and negative predictive value (79.79 vs. 50%; 68.85 vs. 51.55%, respectively), but lower specificity and positive predictive value (84 vs. 100%; 90.36 vs. 100%, respectively). The multivariate analysis revealed that the percentage of CSF EpCAM+ cells predicted an increased risk of death (HR: 1.012, 95% CI 1.000-1.023; p=0.041). A cut-off value of 8% EpCAM+ cells in the CSF distinguished two groups of patients with statistically significant differences in overall survival (OS) (p=0.018). This cut-off value kept its statistical significance regardless of the absolute CSF cell-count. The FCI study of the CSF improved the sensitivity for diagnosing LC, but refinement of the technique is needed to improve specificity. Furthermore, quantification of CSF EpCAM+ cells was revealed to be an independent prognostic factor for OS in patients with LC eligible for therapy. An 8% cut-off value contributed to predicting clinical evolution before initiation of therapy.

Differences in cerebrospinal fluid inflammatory cell reaction of patients with leptomeningeal involvement by lymphoma and carcinoma

Dissemination of neoplastic cells into the cerebrospinal fluid (CSF) and leptomeninges is a devastating complication in patients with epithelial cell neoplasia (leptomeningeal carcinomatosis [LC]) and lymphomas (lymphomatous meningitis [LyM]). Information about the surrounding inflammatory cell populations is scarce. In this study, flow cytometry immunophenotyping was used to describe the distribution of the main leukocyte populations in the CSF of 83 patients diagnosed with neoplastic meningitis (LC, n = 65; LyM, n = 18). These data were compared with those obtained in the CSF from 55 patients diagnosed with the same groups of neoplasia without meningeal involvement (solid tumors, n = 36; high-grade lymphoma, n = 19). Median (interquartile) rates of lymphocytes, monocytes, and polymorphonuclear (PMN) cells were 59.7% (range, 35-76.6%), 24% (range, 16-53%), and 1.5% (range, 0-7.6%) in LC, respectively, and 98.5% (range, 70.8-100%), 1.5% (range, 0-29.3%), and 0% in LyM, respectively (P < 0.001). No difference was observed between patients with breast adenocarcinoma (n = 30) and lung adenocarcinoma (n = 21), nor with different rates of malignant CSF involvement. Patients with lymphoma (with or without LyM) had a similar CSF leukocyte distribution, but cancer patients with LC and without LC had a distinctive PMN cell rate (P = 0.002). These data show that CSF samples from patients with LC have a greater number of inflammatory cells and a different leukocyte distribution than seen in the CSF from patients with LyM. Description of PMN cells is a distinctive parameter of patients with LC, compared with the CSF from patients with LyM and patients with cancer but without LC.

Diagnostic utility of cerebrospinal fluid flow cytometry in patients with and without prior hematologic malignancy

Flow cytometry (FCM) is an adjunct study to routine analysis of cerebrospinal fluid (CSF) to investigate for involvement by a hematologic malignancy. However, in our experience, FCM only infrequently detects abnormalities in CSF. To help optimize resources without forfeiting clinically important data, we sought to determine evidence-based indications and criteria for performing FCM on CSF. FCM results of 316 consecutive CSF specimens were retrospectively reviewed and correlated with clinical history, total nucleated cell (TNC) counts, and results of concurrent cytologic review. Of 255 samples adequate for analysis, 54% were from patients with a prior history of hematologic malignancy, of which 12% (17 cases) were abnormal by FCM. Corresponding TNC counts among samples with abnormal FCM ranged from 0-1050 cells/µL, and only 44% showed abnormal morphology on concurrent cytology. Of the remaining 46% of samples from patients with no known history of hematologic malignancy who had CSF sampling for neurological indications, only one (1%) was abnormal by FCM. This specimen had an elevated TNC count (39 cells/µL) but lacked clearly abnormal findings on concurrent cytology. These results support the use of CSF FCM only in patients with a history of hematologic malignancy or, in the absence of such a history, in samples showing pleocytosis. If these criteria were applied to the current cohort using a TNC count cut-off of >5 cells/µL, 23% of samples would have been deferred from testing, resulting in decreased cost, improved efficiency, and reduction in the need for unnecessary testing without a negative impact on clinical care.

Flow cytometric analysis of cerebrospinal fluid has low diagnostic yield in samples without atypical morphology or prior history of hematologic malignancy

OBJECTIVES

To identify pretest characteristics of cerebrospinal fluid (CSF) specimens that will allow the rational use of flow cytometric analysis (FCA) in the diagnosis of hematologic malignancy.

METHODS

Retrospective data were collected on 501 consecutive CSF samples submitted for FCA.

RESULTS

A positive diagnosis of hematologic malignancy was made in 41 specimens (8.2%). Blasts or atypical lymphocytes were noted on Wright-stained slides in 98% of FCA-positive specimens (40/41), and a history of a hematologic malignancy was present in 89% of specimens (34/38). All FCA-positive specimens had atypical morphology or history of hematologic malignancy. Four hundred six specimens (81%) were FCA negative. Of FCA-negative specimens, 7% (30/406) had atypical morphology, and 3% (12/404) had future central nervous system involvement seen within 30 days.

CONCLUSIONS

These data support a policy in which FCA of CSF is actively discouraged unless atypical lymphocytes or blasts are seen or a history of hematologic malignancy is present.

Contribution of cerebrospinal fluid sCD19 levels to the detection of CNS lymphoma and its impact on disease outcome

Flow cytometry (FCM) is more sensitive than conventional cytology for detection of occult leptomeningeal lymphoma; however, some FCM-negative patients show central nervous system (CNS) recurrence. Here, we evaluated the cerebrospinal fluid (CSF) levels of 13 B-cell-associated markers and their contribution to the diagnosis of CNS lymphoma in 91 diffuse large B-cell lymphomas (DLBCL) and 22 Burkitt lymphomas (BLs). From all markers tested, CD19 was the most informative. Thus, higher soluble CD19 (sCD19) levels were associated with a greater frequency of neurological symptoms in DLBCL and BL and with parenchymal CNS lymphoma in DLBCL; sCD19 emerged as a powerful predictor of event-free and overall survival in DLBCL and BL, particularly when combined with FCM detection of CNS disease. These results support the utility of combined FCM detection of lymphoma cells and assessment of sCD19 levels in CSF, for more accurate identification of CNS disease in DLBCL and BL patients.

Guideline on the prevention of secondary central nervous system lymphoma: British Committee for Standards in Haematology

The guideline group was selected to be representative of UK-based medical experts. Ovid MEDLINE, EMBASE and NCBI Pubmed were searched systematically for publications in English from 1980 to 2012 using the MeSH subheading 'lymphoma, CNS', 'lymphoma, central nervous system', 'lymphoma, high grade', 'lymphoma, Burkitt's', 'lymphoma, lymphoblastic' and 'lymphoma, diffuse large B cell' as keywords, as well as all subheadings. The writing group produced the draft guideline, which was subsequently revised by consensus by members of the Haemato-oncology Task Force of the British Committee for Standards in Haematology (BCSH). The guideline was then reviewed by a sounding board of ~50 UK haematologists, the BCSH and the British Society for Haematology (BSH) Committee and comments incorporated where appropriate. The 'GRADE' system was used to quote levels and grades of evidence, details of which can be found in Appendix I. The objective of this guideline is to provide healthcare professionals with clear guidance on the optimal prevention of secondary central nervous system (CNS) lymphoma. The guidance may not be appropriate to patients of all lymphoma sub-types and in all cases individual patient circumstances may dictate an alternative approach. Acronyms are defined at time of first use.

Diagnostic strategies to investigate cerebrospinal fluid involvement in haematological malignancies

Central nervous system (CNS) involvement is a fatal complication of certain haematological malignancies with an incidence as high as 25% in specific leukaemia/lymphoma subtypes. It is often accompanied by 'occult' cerebrospinal fluid (CSF) involvement at diagnosis, which is frequently missed by conventional cytology examination. Unfortunately, a diagnostic gold standard is yet unavailable since CSF morphology may be negative for malignant cells in up to 45% of patients with suspected meningeal involvement. New technologies such as flow cytometry, molecular genetics and newer biomarkers may improve sensitivity and specificity facilitating the diagnosis of CNS involvement as well as effective prophylaxis and successful treatment.

Final results of a multicenter trial addressing role of CSF flow cytometric analysis in NHL patients at high risk for CNS dissemination

This prospective study compared diagnostic and prognostic value of conventional cytologic (CC) examination and flow cytometry (FCM) of baseline samples of cerebrospinal fluid (CSF) in 174 patients with newly diagnosed aggressive non-Hodgkin lymphoma (NHL). FCM detected a neoplastic population in the CSF of 18 of 174 patients (10%), CC only in 7 (4%; P < .001); 11 patients (14%) were discordant (FCM+/CC−). At a median follow-up of 46 months, there were 64 systemic progressions and 10 CNS relapses, including 2 patients with both systemic and CNS relapses. Two-year progression-free and overall survival were significantly higher in patients with FCM− CSF (62% and 72%) compared with those FCM+ CSF (39% and 50%, respectively), with a 2-year CNS relapse cumulative incidence of 3% (95% confidence interval [CI], 0-7) versus 17% (95% CI, 0-34; P = .004), respectively. The risk of CNS progression was significantly higher in FMC+/CC− versus FCM−/CC− patients (hazard ratio = 8.16, 95% CI, 1.45-46). In conclusion, FCM positivity in the CSF of patients with high-risk NHL is associated with a significantly higher CNS relapse risk and poorer outcome. The combination of IV drugs with a higher CNS bioavailability and intrathecal chemotherapy is advisable to prevent CNS relapses in FCM+ patients.