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

Liquid biopsy for improving diagnosis and monitoring of CNS lymphomas: A RANO review

BACKGROUND

The utility of liquid biopsies is well documented in several extracranial and intracranial (brain/leptomeningeal metastases, gliomas) tumors.

METHODS

The RANO (Response Assessment in Neuro-Oncology) group has set up a multidisciplinary Task Force to critically review the role of blood and cerebrospinal fluid (CSF)-liquid biopsy in CNS lymphomas, with a main focus on primary central nervous system lymphomas (PCNSL).

RESULTS

Several clinical applications are suggested: diagnosis of PCNSL in critical settings (elderly or frail patients, deep locations, and steroid responsiveness), definition of minimal residual disease, early indication of tumor response or relapse following treatments, and prediction of outcome.

CONCLUSIONS

Thus far, no clinically validated circulating biomarkers for managing both primary and secondary CNS lymphomas exist. There is need of standardization of biofluid collection, choice of analytes, and type of technique to perform the molecular analysis. The various assays should be evaluated through well-organized central testing within clinical trials.

Flow cytometry for meningeal infiltration in B acute lymphoblastic leukemia in a low middle income country

Meningeal infiltration in children with B acute lymphoblastic leukemia is one of the most serious complications. Timely diagnosis not only significantly enhances treatment efficacy but also leads to improve patient outcome and reduce risk of relapse. This is particularly crucial in low to middle income countries facing health constraints, where optimizing resources is essential. Conventional cytology (CC) study of cerebrospinal fluid (CSF) is considered in different countries to be the Gold-standard despite its low sensitivity (< 50%). The study of CSF by multiparametric flow cytometry (MFC) appears to be an alternative. The aim of our study was to assess MFC analytical performance compared with CC. Our cross sectional study was conducted over a six-month period in the biological hematology department. CSF samples underwent analysis for the presence of blasts using both CC and MFC. Cytological slides of the CSF were prepared by cytocentrifugation in a Shandon Cytospin 4™. Flow cytometric analysis was performed on the BD FACSLyric™ flow cytometer. All statistical analyses were performed using SPSS version 21.0 (SPSS Inc.). Agreement between the two methods was made using the Kappa index and χ2 test. This study was approved by the local ethics committee. Sixty CSF samples from 39 children with B acute lymphoblastic leukemia were analyzed. Meningeal infiltration was detected respectively in 20% of cases by MFC and 5% of cases by CC, with a significant difference p = 0.006. Comparing the two methods, the Kappa coefficient was 0.35, indicating weak agreement between the two methods. Moreover, MFC positivity was higher even for hypocellular samples. Of the 51 hypocellular samples, eight were positive by MFC while they were negative by CC. MFC shows better sensitivity while retaining good specificity for the detection of meningeal involvement. MFC could therefore be a complementary method to CC for detecting blast cells in the central nervous system.

Detection of circulating tumor DNA in plasma of patients with primary CNS lymphoma by digital droplet PCR

BACKGROUND

Primary central nervous system lymphoma (PCNSL) are rare mature B-cell lymphoproliferative diseases characterized by a high incidence of MYD88 L265P and CD79B Y196 hotspot mutations. Diagnosis of PCNSL can be challenging. The aim of the study was to analyze the detection rate of the MYD88 L265P and CD79B Y196 mutation in cell free DNA (cfDNA) in plasma of patients with PCNSL.

METHODS

We analyzed by digital droplet PCR (ddPCR) to determine presence of the MYD88 L265P and CD79B Y196 hotspot mutations in cfDNA isolated from plasma of 24 PCNSL patients with active disease. Corresponding tumor samples were available for 14 cases. Based on the false positive rate observed in 8 healthy control samples, a stringent cut-off for the MYD88 L265P and CD79B Y196 mutation were set at 0.3% and 0.5%, respectively.

RESULTS

MYD88 L265P and CD79B Y196 mutations were detected in 9/14 (64%) and 2/13 (15%) tumor biopsies, respectively. In cfDNA samples, the MYD88 L265P mutation was detected in 3/24 (12.5%), while the CD79B Y196 mutation was not detected in any of the 23 tested cfDNA samples. Overall, MYD88 L265P and/or CD79B Y196 were detected in cfDNA in 3/24 cases (12.5%). The detection rate of the combined analysis did not improve the single detection rate for either MYD88 L265P or CD79B Y196.

CONCLUSION

The low detection rate of MYD88 L265P and CD79B Y196 mutations in cfDNA in the plasma of PCNSL patients argues against its use in routine diagnostics. However, detection of MYD88 L265P by ddPCR in cfDNA in the plasma could be considered in challenging cases.

Recent updates on central nervous system prophylaxis in patients with high-risk diffuse large B-cell lymphoma

The use of central nervous system (CNS) prophylaxis for patients with diffuse large B-cell lymphoma (DLBCL) remains controversial. Although uncommon, CNS relapses are invariably fatal in this otherwise curable disease. Accurate identification of patients at risk and the optimal approach to CNS prophylaxis therefore remains an area of unmet need. The existing literature, largely retrospective in nature, provides mixed conclusions regarding the efficacy of CNS prophylaxis. The utility of CNS prophylaxis has itself been challenged. In this review, we dissect the issues which render the value of CNS prophylaxis uncertain. We first compare international clinical guidelines for CNS prophylaxis. We then interrogate the factors that should be used to identify high-risk patients accurately. We also explore how clinical patterns of CNS relapse have changed in the pre-rituximab and rituximab era. We then discuss the efficacy of CNS-directed approaches, intensification of systemic treatment and other novel approaches in CNS prophylaxis. Improved diagnostics for early detection of CNS relapses and newer therapeutics for CNS prophylaxis are areas of active investigation. In an area where prospective, randomized studies are impracticable and lacking, guidance for the use of CNS prophylaxis will depend on rigorous statistical review of retrospective data.

Molecular Analysis of Liquid Vitreous Biopsy Reveals Occult Lymphoma Following Cytology-Negative Biopsies of the Brain and Vitreous

PURPOSE

Primary central nervous system lymphoma (PCNSL) is a rare but deadly malignancy that principally affects adults in the fifth and sixth decades of life. Despite diagnostic advances in analyses of cerebral spinal fluid and neuroimaging, definitive diagnosis of PCNSL requires primary brain tissue biopsy. While small neurosurgical biopsy volumes are pursued to minimize removal of normal brain tissue, the spatial margins to precisely biopsy pathologic tissue are narrow and can result in missed diagnoses. Furthermore, prior steroid treatment can significantly reduce tumor burden increasing the likelihood of a non-diagnostic biopsy.

METHODS

A retrospective case report from a tertiary referral center using a combination of neuroradiological studies, sterotactic tissue biopsy, and molecular testing for genome mutations.

RESULTS

A 72-year-old woman with strong suspicion for PCNSL clinically and radiologically, but cerebral spinal fluid and primary brain tissue biopsy were negative for tumor. However, vitreous liquid biopsy molecular testing for a MYD88 mutation as well as B-cell clonality (IGH/IGK rearrangement) were positive, indicating the presence of secondary vitreoretinal lymphoma from PCNSL. Only after autopsy of her brain was histopathological and immunohistochemical evidence of PCNSL confirmed.

CONCLUSION

This case illustrates the unique contribution of liquid biopsy neuropathology-oriented molecular testing in a challenging case with high clinical suspicion of PCNSL in which gold-standard diagnostic testing failed to yield a diagnosis.

Combining MYD88 L265P mutation detection and clonality determination on CSF cellular and cell-free DNA improves diagnosis of primary CNS lymphoma

Diagnosis of primary central nervous system lymphoma (PCNSL) is challenging, and although brain biopsy remains the gold standard, cerebrospinal fluid (CSF) constitutes a less invasive source of lymphomatous biomarkers. In a retrospective cohort of 54 PCNSL cases tested at diagnosis or relapse, we evaluated the contribution of immunoglobulin heavy chain (IGH) gene clonality and MYD88 L265P detection on both CSF cell pellets and supernatants, in comparison with cytology, flow cytometry, interleukin (IL)-10 and IL-6 quantification. Clonality assessment included a new assay to detect partial IGH-DJ rearrangements. Clonal IGH rearrangements and/or MYD88 L265P mutation were detected in 27 (50%) cell pellets and 24 (44%) supernatant cell-free (cf) DNA. Combining analyses on both compartments, 36 (66%) cases had at least one detectable molecular marker, present only in cfDNA for 9 (16%) of them. While cytology and flow cytometry were positive in only 7 (13.0%) and 9 (17.3%) cases respectively, high IL-10 levels were observed in 36 (66.7%) cases. Overall, taking into account molecular and cytokine results, 46/54 (85%) cases had at least one lymphomatous biomarker detectable in the CSF. These results show that this combination of biomarkers evaluated on both cell pellet and supernatant CSF fractions improves significantly the biological diagnosis of PCNSL.

Primary meningeal central nervous system lymphoma: A case report and literature review

RATIONALE

Primary central nervous system lymphoma (PCNSL) is a rare extranodal non-Hodgkin lymphoma, and isolated meningeal PCNSL, without evidence of parenchymal involvement, is even less common, occurring in only 10% to 15% of cases.

PATIENT CONCERNS

A 65-years-old female presented to our hospital with progressive lower extremity motor dysfunction and blurred vision. The initial neurological examination revealed decreased muscle strength in both lower extremities and sensory dysfunction of lower extremities, saddle area, and buttocks. Brain magnetic resonance imaging showed no abnormalities. Lumbar enhanced magnetic resonance imaging showed T11 to L3 horizontal meningeal enhancement. Cerebrospinal fluid (CSF) cytology revealed lymphoma cells. Immunohistochemistry and flow cytometry of the CSF were performed as auxiliary methods to establish the diagnosis of lymphoma.

DIAGNOSES

The patient was diagnosed primary meningeal central nervous system lymphoma.

INTERVENTIONS

During hospitalization, the patient was treated with 2 courses of high-dose intrathecal methotrexate and rituximab combined with intrathecal chemotherapy and supportive treatment.

OUTCOMES

After 2 years of follow-up, the patient was able to walk and take care of herself.

LESSONS

Cases of PCNSL involving only the meninges are rare. Multimodal analysis of the CSF comprises an important component of the diagnostic work-up for patients with primary meningeal central nervous system lymphoma.

Diagnostic value of lumbar puncture for the etiological assessment of uveitis: a retrospective cohort of 188 patients

AIM

To assess the relevance of lumbar puncture (LP) for the etiological diagnosis of uveitis and to establish predictive factors associated with its contributory use.

METHODS

We performed a retrospective study of patients with de novo uveitis who were referred to our tertiary hospital for etiological diagnosis of uveitis, between January 2003 and July 2018. We included patients who underwent a LP as part of the etiological assessment of uveitis. LP was considered as contributory if it led to the etiological diagnosis or to correct the initially suspected diagnosis.

RESULTS

One hundred eighty eight of the 1211 patients referred for evaluation (16%) had an LP, among these patients, 93 (49.4%) had abnormal results including 69 (36.7%) patients with hypercellularity, 69 (36.7%) with hyperproteinorachia, and 28 (14.9%) with oligoclonal bands and/or increased IgG index. LP was considered as contributing to the diagnosis in only 31 (16.4%) cases, among which there were 10 (5.3%) contributions to the etiological diagnosis and 21 (11.2%) modifications in the diagnosis classification. Multivariate analysis established that African ethnicity (p < 0.001), bilateral uveitis (p = 0.01), presence of macular edema or retinal serous detachment (p = 0.048), presence of retinal vasculitis (p < 0.001), presence of neurological signs or symptoms (p = 0.01), and contributing cerebral MRI (p < 0.001) were all significantly associated with a contributory LP. LP did not lead to any therapeutic modification.

CONCLUSION

LP direct contribution to the diagnosis was rare and most often detected non-specific abnormalities. LP should be performed only in cases of neurological clinical signs or symptoms, suspicion of multiple sclerosis, Vogt-Koyanagi-Harada, or syphilis.

Cerebrospinal Fluid Flow Cytometry: Utility in Central Nervous System Lymphoma Diagnosis

BACKGROUND

Flow cytometry of the cerebrospinal fluid (CSF) is used in isolation or as an adjunct to cytology to increase the sensitivity of detecting central nervous system (CNS) lymphoma. We aimed to evaluate the sensitivity of CSF flow cytometry as a diagnostic screening tool for primary CNS lymphoma in patients presenting with undifferentiated neurologic symptoms.

METHODS

We retrospectively reviewed all CSF samples received by the Calgary Laboratory Services Flow Cytometry Laboratory from 2012 to 2015. Clinical data, laboratory investigations, radiologic imaging studies, and pathological data were analyzed. Clinical review extended to 2 years post-CSF flow cytometric testing.

RESULTS

Only 43/763 (5.6%) samples of CSF flow cytometry in 28/573 (4.9%) patients were found to be positive for a hematological malignancy in patients with undifferentiated neurologic symptoms. The overall sensitivity of the test was 13.8% with 25 patients with negative CSF flow cytometry later having a positive biopsy for CNS lymphoma. CSF flow cytometry was negative in all cases when at the time of CSF examination the patient did not have a previous hematological malignancy or findings of abnormal enhancement on MRI (n = 249).

CONCLUSION

CSF flow cytometry has low utility in screening for primary CNS lymphoma in the absence of a previous history of hematologic malignancy or findings of abnormal enhancement on MRI.

Liquid Biopsy and Other Non-Invasive Diagnostic Measures in PCNSL

Simple Summary

Primary central nervous system lymphoma (PCNSL) is an uncommon disease accounting for around 3% of primary CNS tumors. PCNSL exhibits aggressive clinical behavior and has an overall poor prognosis. The clinical presentation is variable, and there are no specific symptoms. Despite progress in radiographic neuroimaging, stereotactic brain biopsy remains obligatory for definitive diagnosis. Advanced standard diagnostics, including CSF cytology and flow cytometry, have limited sensitivity. Accordingly, there is an urgent need to improve the diagnostic tools for PCNSL, including novel non-invasive procedures. The aim of this review is to present and discuss modern methods that have the potential to contribute standard clinical diagnostics within the next few years.

Abstract

Primary central nervous system lymphoma is a rare but highly aggressive form of non-Hodgkin lymphoma that remains confined to the CNS neuroaxis. The diagnosis of PCNSL requires a high level of suspicion as clinical presentation varies depending on the involved CNS areas. Neurological symptoms and MRI findings may mimic gliomas, demyelinating lesions, or infectious and granulomatous diseases. Almost all PCNSL patients undergo invasive surgical procedures for definite diagnosis. Stereotactic biopsy is still the gold standard in achieving a diagnostic accuracy of 73–97%. Both the potential procedural morbidity and mortality, as well as the time to definite histopathologic diagnosis resulting in delays of treatment initiation, have to be considered. On the contrary, minimally invasive procedures, such as MRI, CSF cytology, and flow cytometry, still have limited value due to inferior specificity and sensitivity. Hence, novel diagnostic approaches, including mutation analyses (MYD88) in circulating tumor DNA (ctDNA) and the determination of microRNAs (miR-21, miR-19b, and miR-92) as well as cytokine levels (IL10 and IL6) in blood, cerebrospinal fluid (CSF), and vitreous fluid (VRF), move into the focus of investigation to facilitate the diagnosis of PCNSL. In this review, we outline the most promising approaches that are currently under clinical consideration.

A Rapid Genotyping Panel for Detection of Primary Central Nervous System Lymphoma

Diagnosing primary central nervous system lymphoma (PCNSL) frequently requires neurosurgical biopsy due to nonspecific radiologic features and the low yield of cerebrospinal fluid (CSF) studies. We characterized the clinical evaluation of suspected PCNSL (N=1007 patients) and designed a rapid multiplexed genotyping assay for MYD88, TERT promoter, IDH1/2, H3F3A, and BRAF mutations to facilitate the diagnosis of PCNSL from CSF and detect other neoplasms in the differential diagnosis. Among 159 patients with confirmed PCNSL, the median time to secure a diagnosis of PCNSL was 10 days, with a range of 0-617 days. Permanent histopathology confirmed PCNSL in 142/152 biopsies (93.4%), whereas CSF analyses were diagnostic in only 15/113 samplings (13.3%). Among 86 archived clinical specimens, our targeted genotyping assay accurately detected hematologic malignancies with 57.6% sensitivity and 100% specificity (95% CI: 44.1-70.4% and 87.2-100%, respectively). MYD88 and TERT promoter mutations were prospectively identified in DNA extracts of CSF obtained from patients with PCNSL and glioblastoma, respectively, within 80 minutes. Across 132 specimens, hallmark mutations indicating the presence of malignancy were detected with 65.8% sensitivity and 100% specificity (95% CI: 56.2-74.5% and 83.9-100%, respectively). This targeted genotyping approach offers a rapid, scalable adjunct to reduce diagnostic and treatment delays in PCNSL.

Cell free circulating tumor DNA in cerebrospinal fluid detects and monitors central nervous system involvement of B-cell lymphomas

The levels of cell free circulating tumor DNA (ctDNA) in plasma correlate with treatment response and outcome in systemic lymphomas. Notably, in brain tumors, the levels of ctDNA in the cerebrospinal fluid (CSF) are higher than in plasma. Nevertheless, their role in central nervous system (CNS) lymphomas remains elusive. We evaluated the CSF and plasma from 19 patients: 6 restricted CNS lymphomas, 1 systemic and CNS lymphoma, and 12 systemic lymphomas. We performed whole exome sequencing or targeted sequencing to identify somatic mutations of the primary tumor, then variant-specific droplet digital polymerase chain reaction was designed for each mutation. At time of enrollment, we found ctDNA in the CSF of all patients with restricted CNS lymphoma but not in patients with systemic lymphoma without CNS involvement. Conversely, plasma ctDNA was detected in only 2 out of 6 patients with restricted CNS lymphoma with lower variant allele frequencies than CSF ctDNA. Moreover, we detected CSF ctDNA in one patient with CNS lymphoma in complete remission and in one patient with systemic lymphoma, 3 and 8 months before CNS relapse was confirmed, indicating that CSF ctDNA might detect CNS relapse earlier than conventional methods. Finally, in two cases with CNS lymphoma, CSF ctDNA was still detected after treatment even though no tumoral cells were observed by flow cytometry (FC), indicating that CSF ctDNA detected residual disease better than FC. In conclusion, CSF ctDNA can detect CNS lesions better than plasma ctDNA and FC. In addition, CSF ctDNA predicted CNS relapse in CNS and systemic lymphomas.

The Wide Spectrum of Pathophysiologic Mechanisms of Paraproteinemic Neuropathy

Monoclonal gammopathy is encountered quite frequently in the general population. This type of hematologic abnormality may be mild, referred to as monoclonal gammopathy of undetermined significance or related to different types of hematologic malignancies. The association of a peripheral neuropathy with monoclonal gammopathy is also fairly common, and hemopathy may be discovered in an investigation of peripheral neuropathy. In such a situation, it is essential to determine the exact nature of the hematologic process in order not to miss a malignant disease and thus initiate the appropriate treatment (in conjunction with hematologists and oncologists). In this respect, nerve biopsy (discussed on a case-by-case basis) is of great value in the management of such patients. We therefore propose to present the objectives and main interests of nerve biopsy in this situation.

Standardizing a volume benchmark for cerebrospinal fluids for optimal diagnostic accuracy

INTRODUCTION

Cerebral spinal fluid (CSF) cytomorphologic analysis remains the gold standard in the evaluation of malignant leptomeningeal involvement. However, collection of optimal volumes for adequate cytomorphologic evaluation is not standardized. Our study investigated optimal CSF volumes that result in a significant diagnostic result.

METHODS

A total of 4114 samples were retrospectively identified from 2014 to 2018, and 2557 samples had concurrent flow cytometry (FC) study. Each specimen was grouped as unsatisfactory, negative, atypical, or positive. Positive samples were grouped as either solid tumors, leukemia, or lymphoma by the type of malignancy detected. Demographic data as well as CSF source was recorded. Specimens with FC were separated by detection on cytology and/or FC. A t-test and ANOVA test were used to compare the average volumes for each group.

RESULTS

Average volumes for negative, atypical, and positive samples are 7.48 mL (95% CI: 7.33, 7.63), 7.97 mL (95% CI: 7.37, 8.57), and 8.44 mL (95% CI: 7.46, 9.43), respectively. Average volumes for solid tumors, leukemia, and lymphoma positive samples are 12.0 mL (95% CI: 9.11, 14.89), 6.73 mL (95% CI: 5.94, 7.53), and 8.44 mL (95% CI: 6.78, 10.09). For cases with FC, the volumes are 10.11 mL (95% CI: 9.28, 10.96), 7.28 mL (95% CI: 6.87, 7.70), and 6.86 mL (95% CI: 6.25, 7.49) for positive cytology only, positive cytology/FC, and negative for both, respectively.

CONCLUSIONS

Our results suggest that higher volumes produce better results for analysis. We recommend an optimal volume of 8.44 mL for cytologic work-up of malignancies. However, optimal volumes may differ based upon malignancy type and utilization of flow cytometry.

Lymphomatosis cerebri with cauda equina lymphoma

PURPOSE/AIM

Lymphomatosis cerebri (LC) and cauda equina lymphoma are both rare forms of primary central nervous system lymphoma (PCNSL). LC is characterized by diffuse bilateral non-enhancing (or partially enhancing) inltrative lesions without mass effect, which can be easily confused with other forms of leukoencephalopathy and, thus, lead to delays in diagnosis.

CASE REPORT

For the first time, a case of LC concomitant with cauda equina involvement confirmed by brain stereotactic biopsy is presented.

CONCLUSIONS

This case highlights the necessity of using a multimodal strategy in diagnosing PCNSL, including multimodal magnetic resonance, cerebral spinal fluid cytology, flow cytometry and fluorodeoxyglucose positron emission tomography/computed tomography.

Initial Diagnostic Work-Up of Acute Leukemia: ASCO Clinical Practice Guideline Endorsement of the College of American Pathologists and American Society of Hematology Guideline

PURPOSE

The College of American Pathologists (CAP) and the American Society of Hematology (ASH) developed an evidence-based guideline on the initial diagnostic work-up of acute leukemia (AL). Because of the relevance of this topic to the ASCO membership, ASCO reviewed the guideline and applied a set of procedures and policies for endorsing clinical practice guidelines that have been developed by other professional organizations.

METHODS

The CAP-ASH guideline on initial diagnostic work-up of AL was reviewed for developmental rigor by methodologists. Then, an ASCO Endorsement Expert Panel updated the literature search and reviewed the content and recommendations.

RESULTS

The ASCO Expert Panel determined that the recommendations from the guideline, published in 2016, are clear, thorough, and based on the most relevant scientific evidence. ASCO fully endorsed the CAP-ASH guideline on initial diagnostic work-up of AL and included some discussion points according to clinical practice and updated literature.

CONCLUSION

Twenty-seven guideline statements were reviewed. Some discussion points were included to better assess CNS involvement in leukemia and to provide novel insights into molecular diagnosis and potential markers for risk stratification and target therapy. These discussions are categorized into four sections: (1) initial diagnosis focusing on basic diagnostics and determination of risk parameters, (2) molecular markers and minimal residual disease detection, (3) context of referral to another institution with expertise in the management of AL, and (4) reporting and record keeping for better outlining and follow-up discussion. Additional information is available at: www.asco.org/hematologic-malignancies-guidelines .

Primary CNS Lymphomas: Challenges in Diagnosis and Monitoring

Primary Central Nervous System Lymphoma (PCNSL) is a rare neoplasm that can involve brain, eye, leptomeninges, and rarely spinal cord. PCNSL lesions most typically enhance homogeneously on T1-weighted magnetic resonance imaging (MRI) and appear T2-hypointense, but high variability in MRI features is commonly encountered. Neurological symptoms and MRI findings may mimic high grade gliomas (HGGs), tumefactive demyelinating lesions (TDLs), or infectious and granulomatous diseases. Advanced MRI techniques (MR diffusion, spectroscopy, and perfusion) and metabolic imaging, such as Fluorodeoxyglucose Positron Emission Tomography (FDG-PET) or amino acid PET (usually employing methionine), may be useful in distinguishing these different entities and monitoring the disease course. Moreover, emerging data suggest a role for cerebrospinal fluid (CSF) markers in predicting prognosis and response to treatments. In this review, we will address the challenges in PCNSL diagnosis, assessment of response to treatments, and evaluation of potential neurotoxicity related to chemotherapy and radiotherapy.

Northern Italy in the American South: Assessing interobserver reliability within the Milan System for Reporting Salivary Gland Cytopathology

BACKGROUND

The Milan System for Reporting Salivary Gland Cytopathology (MSRSGC) has been proposed to standardize salivary gland fine-needle aspiration (FNA) diagnoses. This study assessed salivary gland FNA results and risk of malignancy (ROM) rates at the University of North Carolina as well as the interobserver reliability (IOR) of the atypia of undetermined significance (AUS) and salivary gland neoplasm of uncertain malignant potential (SUMP) categories.

METHODS

The electronic medical record was searched for FNA cases from 2010 to 2017 with subsequent surgical resections. Histologic diagnosis was used for gold-standard comparison. The original cytologic results were then converted into MSRSGC categories (nondiagnostic, nonneoplastic, AUS, benign neoplasm, SUMP, suspicious, and malignant). For the assessment of IOR, 23 cases were selected with enrichment for cases diagnosed as AUS (n = 11) or SUMP (n = 9). Six boarded cytopathologists and 1 cytopathology fellow assessed representative slides and provided an MSRSGC diagnosis for each case. Fleiss' κ coefficients were calculated to determine IOR.

RESULTS

The ROM was 33% for both AUS and SUMP cases; however, the risk of neoplasia was 56% for AUS cases and 100% for SUMP cases. Fleiss' κ for the AUS category was 0.217 (P < .05), and Fleiss' κ for the SUMP category was 0.024 (P = .74).

CONCLUSIONS

In this study assessing the IOR of MSRSGC categories, fair agreement and slight agreement were found for the AUS and SUMP categories, respectively. Observers preferentially used the AUS or benign neoplasm category for SUMP cases, perhaps because of unfamiliarity with SUMP as a diagnostic option. The initial adoption of a new reporting system will require a quality assessment to ensure that the system is reliable and useful for clinicians. Cancer Cytopathol 2018;126:390-6. © 2018 American Cancer Society.

Work-up and management of a high-risk patient with primary central nervous system lymphoma

Primary central nervous system lymphoma (PCNSL) is a rare disorder that, in 95% of cases, represents diffuse large B-cell lymphoma. As such, making an accurate diagnosis is important. At present, stereotactic-guided biopsy is a recognized method of choice for tissue analysis. However, the diagnostic work-up for high-risk patients is determined by their performance status. Here, we report a case of PCNSL in a high-risk patient, for whom diagnosis was established by cerebrospinal fluid cytology and flow cytometry, which significantly shortened a diagnostic work-up period and allowed for the immediate treatment of the patient.

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.

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.