Cytometry Part B: Clinical Cytometry最新文献

{"title":"The patterns and diagnostic significance of the lack of surface immunoglobulin light chain on mature B cells in clinical samples for lymphoma workup","authors":"Sara L. Huang,&nbsp;Thomas Fennell,&nbsp;Xia Chen,&nbsp;James Z. Huang","doi":"10.1002/cyto.b.22107","DOIUrl":"10.1002/cyto.b.22107","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Surface immunoglobulin (sIg) light chains are not always detected on mature B cells. This may present as a challenge for clonality determination in clinical flow cytometry.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>To explore the mechanism and diagnostic significance of sIg negative mature B cells, we retrospectively studied 14 cases of sIg negative reactive B-cell lymphocytosis and 89 cases of sIg negative mature B-cell lymphomas. The expression patterns of sIg and cytoplasmic immunoglobulin (cIg) light chains were studied by flow cytometry using both monoclonal and polyclonal antibodies.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>These 14 cases of sIg negative reactive B-cell lymphocytosis were proven to be polytypic based on cytoplasmic light chain studies. In 89 cases of sIg negative mature B-cell lymphomas, we described four distinct patterns of abnormal light chain expression including partial or complete loss of sIg or cIg, suggesting different underlying mechanisms.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>This study represents the first reported series of body or cystic fluids where reactive B cells do not have detectable sIg, arguing strongly against making a diagnosis of B-cell lymphoma based on lack of sIg in mature B cells. Since the lack of sIg does not always predict clonal/neoplastic mature B-cell proliferation, further cIg evaluation should be performed when sIg expression is not detected in mature B cells. The lack of both sIg and cIg in mature B cells may serve as a reliable surrogate clonality/neoplastic marker.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9925296","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Circulating CD22+/CD19−/CD24− progenitors and CD22+/CD19+/CD24− mature B cells: Diagnostic pitfalls for minimal residual disease detection in B-lymphoblastic leukemia","authors":"Ting Zhou,&nbsp;Jeremiah Karrs,&nbsp;Truc Ho,&nbsp;Alyssa Doverte,&nbsp;James N. Kochenderfer,&nbsp;Nirali N. Shah,&nbsp;Constance M. Yuan,&nbsp;Hao-Wei Wang","doi":"10.1002/cyto.b.22104","DOIUrl":"10.1002/cyto.b.22104","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Multiparametric flow cytometry (MFC) has become a powerful tool in minimal residual disease (MRD) detection in B-lymphoblastic leukemia/lymphoma (B-ALL). In the setting of targeted immunotherapy, B-ALL MRD detection often relies on alterative gating strategies, such as the utilization of CD22 and CD24. It is important to depict the full diversity of normal cell populations included in the alternative B-cell gating methods to avoid false-positive results. We describe two CD22-positive non-neoplastic cell populations in the peripheral blood (PB), including one progenitor population of uncertain lineage and one mature B-cell population, which are immunophenotypic mimics of B-ALL.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Using MFC, we investigated the prevalence and phenotypic profiles of both CD22-positive populations in 278 blood samples from 52 patients with B-ALL; these were obtained pre- and post-treatment with CD19 and/or CD22 CAR-T therapies. We further assessed whether these two populations in the blood were exclusively associated with B-ALL or recent anticancer therapies, by performing the same analysis on patients diagnosed with other hematological malignancies but in long-term MRD remission.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>The progenitor population and mature B-cell population were detected at low levels in PB of 61.5% and 44.2% of B-ALL patients, respectively. Both cell types showed distinctive and highly consistent antigen expression patterns that are reliably distinguishable from B-ALL. Furthermore, their presence is not restricted solely to B-ALL or recent therapy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>Our findings aid in building a complete immunophenotypic profile of normal cell populations in PB, thereby preventing misdiagnosis of B-ALL MRD and inappropriate management.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10032883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Multicenter prospective evaluation of diagnostic potential of flow cytometric aberrancies in myelodysplastic syndromes by the ELN iMDS flow working group","authors":"Wolfgang Kern,&nbsp;Theresia M. Westers,&nbsp;Frauke Bellos,&nbsp;Marie Christine Bene,&nbsp;Peter Bettelheim,&nbsp;Lisa Eidenschink Brodersen,&nbsp;Kate Burbury,&nbsp;Sung-Chao Chu,&nbsp;Matthew Cullen,&nbsp;Matteo Della Porta,&nbsp;Alan Stewart Dunlop,&nbsp;Ulrika Johansson,&nbsp;Sergio Matarraz,&nbsp;Uta Oelschlaegel,&nbsp;Kiyoyuki Ogata,&nbsp;Anna Porwit,&nbsp;Frank Preijers,&nbsp;Katherina Psarra,&nbsp;Leonie Saft,&nbsp;Dolores Subirá,&nbsp;Elisabeth Weiß,&nbsp;Vincent H. J. van der Velden,&nbsp;Arjan van de Loosdrecht","doi":"10.1002/cyto.b.22105","DOIUrl":"10.1002/cyto.b.22105","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Myelodysplastic syndromes (MDS) represent a diagnostic challenge. This prospective multicenter study was conducted to evaluate pre-defined flow cytometric markers in the diagnostic work-up of MDS and chronic myelomonocytic leukemia (CMML).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>Thousand six hundred and eighty-two patients with suspected MDS/CMML were analyzed by both cytomorphology according to WHO 2016 criteria and flow cytometry according to ELN recommendations. Flow cytometric readout was categorized ‘non-MDS’ (i.e. no signs of MDS/CMML and limited signs of MDS/CMML) and ‘in agreement with MDS’ (i.e., in agreement with MDS/CMML).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Flow cytometric readout categorized 60% of patients in agreement with MDS, 28% showed limited signs of MDS and 12% had no signs of MDS. In 81% of cases flow cytometric readouts and cytomorphologic diagnosis correlated. For high-risk MDS, the level of concordance was 92%.</p>\u0000 \u0000 <p>A total of 17 immunophenotypic aberrancies were found independently related to MDS/CMML in ≥1 of the subgroups of low-risk MDS, high-risk MDS, CMML. A cut-off of ≥3 of these aberrancies resulted in 80% agreement with cytomorphology (20% cases concordantly negative, 60% positive). Moreover, &gt;3% myeloid progenitor cells were significantly associated with MDS (286/293 such cases, 98%).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>Data from this prospective multicenter study led to recognition of 17 immunophenotypic markers allowing to identify cases ‘in agreement with MDS’. Moreover, data emphasizes the clinical utility of immunophenotyping in MDS diagnostics, given the high concordance between cytomorphology and the flow cytometric readout. Results from the current study challenge the application of the cytomorphologically defined cut-off of 5% blasts for flow cytometry and rather suggest a 3% cut-off for the latter.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9169766","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow cytometry in the diagnosis of myelodysplastic syndromes","authors":"Wolfgang Kern,&nbsp;Arjan van de Loosdrecht","doi":"10.1002/cyto.b.22103","DOIUrl":"10.1002/cyto.b.22103","url":null,"abstract":"<p>In hematologic neoplasms, the identification of recurrent disease-associated phenotypic features in general is followed after a prolonged period by the identification of disease-associated and even disease-defining genetic changes based on which specific treatment will be developed. As an example, for chronic myelogenous leukemia (CML) this has taken one and a half century from the first publication on morphology (Virchow, <span>1845</span>) to the first report on a tyrosin-kinase inhibitor (Druker et al., <span>2001</span>). For myelodysplastic syndromes (MDS) the interval between publication of morphologic classification system (Bennett et al., <span>1982</span>) and the most recent WHO classification applying genetic criteria for diagnostics (Khoury et al., <span>2022</span>) the interval has been significantly shorter. For various reasons, the role of immunophenotypic features of MDS and their flow cytometric identification had been neglected for a long time.</p><p>Following pivotal publication on the topic by Denise Wells and Mike Loken (Wells et al., <span>2003</span>) flow cytometrists became increasingly interested and gathered together in 2007 at the MDS Foundation Conference in Florence, Italy, which proved to be the founding hour of the “ELN iMDS flow working group.” Each member of the group has focused their research on assessing the diagnostic application of flow cytometry in MDS. Since 2007, the ELN iMDS flow working group has held yearly meetings to discuss progress in research activities as well as to divise consensus guideline publications aiming to apply flow cytometry in a valid manner for in the diagnostic setting of MDS (Porwit, <span>2014</span>; van de Loosdrecht et al., <span>2009</span>; van de Loosdrecht et al., <span>2013</span>; Westers et al., <span>2012</span>; Westers et al., <span>2017</span>). These meetings allowed not only for continuous scientific discussion between experts from worldwide (i.e., although formed under the roof of the European LeukemiaNet members came from North America, Europe, Asia and Australia) but also for friendships reaching beyond any scientific scope.</p><p>This Special Issue of Clinical Cytometry on the application of flow cytometry in the diagnostic setting of MDS comprises a variety of different papers from the ELN iMDS flow working group reaching from updated consensus guidelines over multi center studies to research results generated by the members of the group. It has been our pleasure to coordinate this group for one and a half decades and we hope the readers of the Special Issue enjoy reading the articles and get stimulated to add their research to the topic.</p><p>Wolfgang Kern declares part ownership of MLL Munich Leukemia Laboratory.</p>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cyto.b.22103","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9169763","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Issue highlights—November 2022","authors":"János Kappelmayer MD PhD","doi":"10.1002/cyto.b.22101","DOIUrl":"10.1002/cyto.b.22101","url":null,"abstract":"<p>In patients with interstitial lung diseases (ILD) broncho-alveolar lavage (BAL) fluid analysis is important in supporting the diagnosis. The suggested site for obtaining diagnostic BAL is the middle lobe of the patient's lungs when it is washed with isotonic saline and the aspirated solution is analyzed for cell concentration and leukocyte subsets. The procedure for obtaining BAL fluid is quite difficult to standardize and the washing and harvesting procedure is usually carried out in five fractions. In ILD like sarcoidosis, idiopathic pulmonary fibrosis, or eosinophilic ILD, BAL fluid analysis can aid in the diagnosis while in other diseases like primary alveolar proteinosis a therapeutic BAL is applied as drug treatment in these cases, which often fail.</p><p>In this issue of <i>Clinical Cytometry</i> two manuscripts from the same group deal with flow cytometric BAL analysis. In the manuscript of Eidhof et al. (<span>2021</span>) the authors compare three methods to stabilize BAL cells for flow cytometric analysis. This procedure has a large practical significance, as cells in the low protein content BAL fluid are quite vulnerable. Samples should be kept on ice and transported to the laboratory and stained within 4 h, otherwise they tend to lyse. In their article, the authors present the comparison of native lavage cells versus stabilized cells utilizing Transfix, Streck Cell Preservative and an in-house method that primarily consists of formaldehyde fixation in buffered conditions containing serum proteins. All three stabilization methods influence the side scatter (SSC) but this does not affect gating. They found a 7-day stability with Transfix and a 28-day stability with their in-house method that can considerably expand the list of laboratories where samples can be transported under the above conditions.</p><p>In their other paper, this group by Mulder et al. (<span>2022</span>) demonstrate the results of their external quality flow cytometric studies. Starting from year 2000 with only 12 participating laboratories they are now involving 42 flow labs. The external QC programme required on one hand the actual analysis of the cytometric items that consisted of leukocyte count, leukocyte differentiation, lymphocyte subsets, T-cell subsets related to peripheral blood and CD103 expression on CD4+ cells with microscopic analysis. On the other hand, the participants received relevant clinical information about each case and were able to report their interpretive comments and their diagnosis as free text. The best matches with the diagnosis were obtained for sarcoidosis, eosinophilic ILD and extrinsic alveolitis, that would advance the diagnosis of these patients.</p><p>In the past decade the implementation of immunotherapy in the treatment of numerous hematological disorders has become a daily practice. The utilization of rituximab has been incorporated into several treatment protocols making it impossible to use anti-CD20 for the identificatio","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cyto.b.22101","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10686641","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Adaptation of a multiple myeloma minimal residual disease multicolor flow cytometry assay for real-world practice","authors":"Annabel McMillan,&nbsp;Thien-An Tran,&nbsp;Daria Galas-Filipowicz,&nbsp;Marquita Camilleri,&nbsp;Catherine Lecat,&nbsp;Louise Ainley,&nbsp;Yanping Guo,&nbsp;Kwee Yong,&nbsp;Jonathan Sive","doi":"10.1002/cyto.b.22100","DOIUrl":"10.1002/cyto.b.22100","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Achieving minimal residual disease (MRD) negativity following treatment for multiple myeloma (MM) is associated with improved progression free and overall survival. In the UK, MRD assessments in MM are not incorporated into routine clinical use outside trials. Widely used in other haematological malignancies, there is a role for widening the availability of myeloma MRD assays to laboratories outside larger treating centers.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We set up and assessed concordance of a multicolor flow cytometry (MCF) assay for MM MRD in collaboration with a reference center including validity following delayed processing of samples using an optimized fixation step. We then conducted a real-world snapshot of MRD results in a cohort of newly diagnosed transplant-eligible patients treated with UK standard induction therapies at the time of analysis.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>43 MCF MRD samples run in parallel with a reference center showed high correlation and minimal bias. 24 samples were split and processed in duplicate both fixed and fresh, with strong correlation, minimal bias, and no change in plasma cell phenotype by flow markers confirming a 6-day delay in processing did not affect assay performance. A real-world snapshot found 17% (10/58) of patients were MRD-negative post-bortezomib-based triplet induction therapy.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>We successfully adopted a reference MCF MM MRD method which was stable for up to 6 days following sample collection potentially allowing broader access of this assay to smaller laboratories which would facilitate further investigation of the prognostic value and clinical utility of MRD assessments outside the trial setting in real-world practice.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10092317","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Expression levels and patterns of B-cell maturation antigen in newly diagnosed and relapsed multiple myeloma patients from Indian subcontinent","authors":"Harshini Sriram,&nbsp;Florence Kunjachan,&nbsp;Twinkle Khanka,&nbsp;Sangamitra Gawai,&nbsp;Sitaram Ghogale,&nbsp;Nilesh Deshpande,&nbsp;Karishma Girase,&nbsp;Jagruti Patil,&nbsp;Gaurav Chatterjee,&nbsp;Sweta Rajpal,&nbsp;Nikhil V. Patkar,&nbsp;Bhausaheb Bagal,&nbsp;Hasmukh Jain,&nbsp;Manju Sengar,&nbsp;Syed Khizer Hasan,&nbsp;Navin Khattry,&nbsp;Papagudi G. Subramanian,&nbsp;Sumeet Gujral,&nbsp;Prashant R. Tembhare","doi":"10.1002/cyto.b.22099","DOIUrl":"10.1002/cyto.b.22099","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>Many novel therapies are being evaluated for the treatment of Multiple myeloma (MM). The cell-surface protein B-cell maturation antigen (BCMA, CD269) has recently emerged as a promising target for CAR-T cell and monoclonal-antibody therapies in MM. However, the knowledge of the BCMA expression-pattern in myeloma patients from the Indian subcontinent is still not available. We present an in-depth study of BCMA expression-pattern on abnormal plasma cells (aPC) in Indian MM patients.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Methods</h3>\u0000 \u0000 <p>We studied BM samples from 217 MM patients (211-new and 6-relapsed) with a median age of 56 years (range, 30–78 years &amp; M:F-2.29) and 20 control samples. Expression levels/patterns of CD269 (clone-19f2) were evaluated in aPCs from MM patients and in normal PCs (nPC) from uninvolved staging bone marrow samples (controls) using multicolor flow cytometry (MFC). Expression-level of CD269 was determined as a ratio of mean fluorescent intensity (MFI-R) of CD269 in PCs to that of non-B-lymphocytes and expression-pattern (homogenous/heterogeneous) as coefficient-of-variation of immunofluorescence (CVIF).</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Median (range) percentage of CD269-positive abnormal-PCs in total PCs was 71.6% (0.49–99.29%). The MFI-R (median, range) of CD269 was significantly higher in aPCs (4.13, 1.12–26.88) than nPCs (3.33, 1.23–12.87), <i>p</i> &lt; .0001. Median (range) MFI of CD269 at diagnosis and relapse were 2.39 (0.77–9.57) and 2.66 (2.15–3.23) respectively. CD269 levels were similar at diagnosis and relapse, <i>p</i> = .5529.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusions</h3>\u0000 \u0000 <p>We demonstrated that BCMA/CD269 is highly expressed in aPCs from a majority of MM patients, both at diagnosis and relapse. Thus, BCMA is a valuable target for therapy for Indian MM patients.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cyto.b.22099","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10630699","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mature B- and plasma-cell flow cytometric analysis: A review of the impact of targeted therapy","authors":"Qi Gao,&nbsp;Xueyan Chen,&nbsp;Sindhu Cherian,&nbsp;Mikhail Roshal","doi":"10.1002/cyto.b.22097","DOIUrl":"10.1002/cyto.b.22097","url":null,"abstract":"<p>Flow cytometry has been indispensable in diagnosing B cell lymphoma and plasma cell neoplasms. The advances in novel multicolor flow cytometry have also made this technology a robust tool for monitoring minimal/measurable residual disease in chronic lymphocytic leukemia and multiple myeloma. However, challenges using conventional gating strategies to isolate neoplastic B or plasma cells are emerging due to the rapidly increasing number of antibody therapeutics targeting single or multiple classic B/plasma cell-lineage markers, such as CD19, CD20, and CD22 in B cells and CD38 in plasma cells. This review is the first of a two-part series that summarizes the most current targeted therapies used in B and plasma cell neoplasms and proposes detailed alternative approaches to overcome post-targeted therapy analysis challenges by flow cytometry. The second review in this series (Chen et al.) focuses on challenges encountered in the use of targeted therapy in precursor B cell neoplasms.</p>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9568138","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Flow cytometry to detect bone marrow involvement by follicular lymphoma","authors":"Mercè Aren,&nbsp;Silvia Marce,&nbsp;Rebeca Jurado,&nbsp;Gustavo Tapia,&nbsp;Lluís Puigdefabregues,&nbsp;Minerva Raya,&nbsp;Montserrat Cortes,&nbsp;Montse Garcia-Caro,&nbsp;Jordi Junca,&nbsp;Pablo Mozas,&nbsp;Esther Viñets,&nbsp;Marta Cabezon,&nbsp;Esther Plensa,&nbsp;Milos Miljkovic,&nbsp;Juan-Manuel Sancho,&nbsp;José-Tomas Navarro,&nbsp;Lurdes Zamora,&nbsp;Marc Sorigue","doi":"10.1002/cyto.b.22098","DOIUrl":"10.1002/cyto.b.22098","url":null,"abstract":"<div>\u0000 \u0000 \u0000 <section>\u0000 \u0000 <h3> Background</h3>\u0000 \u0000 <p>High-quality data on bone marrow involvement (BMI) assessed by flow cytometry (FC) in follicular lymphoma (FL) is lacking.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Aims</h3>\u0000 \u0000 <p>We set up a prospective protocol with a 10-color tube and acquisition of 500.000 leukocytes on a Nav flow cytometer for evaluation of BMI in FL by FC.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Materials and methods</h3>\u0000 \u0000 <p>FC was compared with a combination of histopathology and <i>IGH</i> gene rearrangement, which were considered the gold standard. We also compared BMI by FC with PET.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Results</h3>\u0000 \u0000 <p>Fifty-two patients were included (median 67 years, 54% female). BMI by FC was seen in 35 (67%), with a median involvement of 1.2% (interquartile range: 0.3%–7%) of leukocytes. Comparison with the gold standard revealed two false negatives and two false positives (potentially true involvement undetected by the gold standard). BMI by PET was seen in 14/46 (30%). Immunophenotype of FL in the bone marrow was highly heterogeneous. The most common phenotypic abnormality was dim expression of CD19 (&gt;0.5 log loss in 30% of patients). CD10 was negative in 13 (37%) and incompletely positive (overlap with the negative population) in a further 8 (28%) while entirely positive only in 14 (48%). Other abnormalities (loss of CD20, gain or loss of CD79b, expression of CD43, and substantial loss of CD45) were rare. Computational analysis by means of FlowSOM confirmed the heterogeneous phenotype, with FL from different patients clustering in unrelated metaclusters.</p>\u0000 </section>\u0000 \u0000 <section>\u0000 \u0000 <h3> Conclusion</h3>\u0000 \u0000 <p>BMI by FL was frequent and immunophenotype was heterogeneous. However, this protocol enabled detection of FL in bone marrow in the vast majority of patients with bone marrow involvement by the gold standard.</p>\u0000 </section>\u0000 </div>","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-10-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cyto.b.22098","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"9123172","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Biclonality in hairy cell leukemia: Co-occurrence of CD10+ and CD10− clones with different surface membrane immunoglobulin expression","authors":"Marisa Gorrese,&nbsp;Roberto Guariglia,&nbsp;Annapaola Campana,&nbsp;Angela Bertolini,&nbsp;Lucia Fresolone,&nbsp;Maria Carmen Martorelli,&nbsp;Bianca Serio,&nbsp;Carmine Selleri,&nbsp;Valentina Giudice","doi":"10.1002/cyto.b.22096","DOIUrl":"10.1002/cyto.b.22096","url":null,"abstract":"<p>Hairy cell leukemia (HCL), a rare indolent B-cell lymphoproliferative disorder, is characterized by the presence of bone marrow (BM) and peripheral blood hairy cells with cytoplasmic projections, splenomegaly, pancytopenia, and recurrent infections. In most cases, HCL cells harbor a V600E somatic mutation on B-raf proto-oncogene (<i>BRAF</i>), causing constitutive activation of downstream signaling pathways, especially mitogen-activated protein kinase (MEK) 1 and 2. Cytogenetics abnormalities can be also found, such as trisomy 5 and structural modifications on chromosomes 5 and 2, with no recurrent alteration, as well as Cyclin D1 overexpression (Maitre et al., <span>2022</span>). Classical HCL cells are characterized by surface expression of CD19, CD20, CD22, CD11c, CD25, CD79b, CD103, CD123, FMC7, and monoclonal light chain immunoglobulin (SmIg) restriction. These cells are typically negative for CD5, CD10, and CD23; however, CD10 positivity has been reported in 5%–14% of all HCL cases and CD23 positivity in 17%–21% of patients (Maitre et al., <span>2022</span>; Vittoria et al., <span>2021</span>). Therefore, HCL cell immunophenotype resembles that of post-germinal center B lymphocytes, also based on immunoglobulin (Ig) gene rearrangements. Biclonality in non-Hodgkin lymphomas is infrequent accounting for less than 5% of total cases, and in HCL is an even rarer event, only anecdotally reported (Vittoria et al., <span>2021</span>). We present a composite HCL case characterized by distinct expression of CD10 and SmIg. This case represented a diagnostic challenge, highlighting the need of multiparametric flow cytometry immunophenotyping for detection of subclones in lymphoproliferative disorders.</p><p>A 52 years-old male with obesity (BMI, 33) treated with gastric band in 2003 arrived at our observation in March 2022 for neutropenia (620 cells/μl) and thrombocytopenia (68,000 platelets/μl) with normal absolute lymphocyte count (2170 cells/μl) and hemoglobin levels (Hb, 13.4 g/dl; mean corpuscular volume [MCV], 100.8 fl). CT scan showed multiple lymphadenopathies located at the perivascular mediastinal region (aortic arch and left common carotid artery) with maximum diameter of 16 mm, and sub-centimetric left latero-cervical lymphadenopathies. Spleen enlargement (159 × 89 mm²) was also observed. BM biopsy showed a diffuse infiltration (60%) of medium-sized lymphoid cells with abundant cytoplasm and positive for CD20, PAX5, CD25, and CD10. Residual normal hemopoiesis was significantly reduced. Normal karyotype (46, XY) was documented by cytogenetic analysis performed on 20 mitoses, and the typical V600E <i>BRAF</i> mutation was observed by next-generation sequencing (variant allele frequency, 7.5%). Moreover, other several missense mutations of unknown significance were described on <i>TET2</i> (exon 3, Tyr867His and Pro3631Leu; and on exon 11, Leu1721Trp, Pro1723Ser, and His1778Arg), <i>SETBP1</i> (exon 4, Val231Leu, and Val1101Ile),","PeriodicalId":10883,"journal":{"name":"Cytometry Part B: Clinical Cytometry","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2022-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://onlinelibrary.wiley.com/doi/epdf/10.1002/cyto.b.22096","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"10633195","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}